varasm.c revision 74473
1/* Output variables, constants and external declarations, for GNU compiler. 2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 3 1999, 2000, 2001 Free Software Foundation, Inc. 4 5This file is part of GNU CC. 6 7GNU CC is free software; you can redistribute it and/or modify 8it under the terms of the GNU General Public License as published by 9the Free Software Foundation; either version 2, or (at your option) 10any later version. 11 12GNU CC is distributed in the hope that it will be useful, 13but WITHOUT ANY WARRANTY; without even the implied warranty of 14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15GNU General Public License for more details. 16 17You should have received a copy of the GNU General Public License 18along with GNU CC; see the file COPYING. If not, write to 19the Free Software Foundation, 59 Temple Place - Suite 330, 20Boston, MA 02111-1307, 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 <setjmp.h> 33/* #include <stab.h> */ 34#include "rtl.h" 35#include "tree.h" 36#include "flags.h" 37#include "except.h" 38#include "function.h" 39#include "expr.h" 40#include "output.h" 41#include "hard-reg-set.h" 42#include "regs.h" 43#include "defaults.h" 44#include "real.h" 45#include "toplev.h" 46#include "dbxout.h" 47#include "sdbout.h" 48 49#include "obstack.h" 50#include "c-pragma.h" 51 52#ifdef XCOFF_DEBUGGING_INFO 53#include "xcoffout.h" 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 ".stabs" 62#endif 63 64/* Define the prefix to use when check_memory_usage_flag is enable. */ 65#ifdef NO_DOLLAR_IN_LABEL 66#ifdef NO_DOT_IN_LABEL 67#define CHKR_PREFIX "chkr_prefix_" 68#else /* !NO_DOT_IN_LABEL */ 69#define CHKR_PREFIX "chkr." 70#endif 71#else /* !NO_DOLLAR_IN_LABEL */ 72#define CHKR_PREFIX "chkr$" 73#endif 74#define CHKR_PREFIX_SIZE (sizeof (CHKR_PREFIX) - 1) 75 76/* File in which assembler code is being written. */ 77 78extern FILE *asm_out_file; 79 80/* The (assembler) name of the first globally-visible object output. */ 81char *first_global_object_name; 82char *weak_global_object_name; 83 84extern struct obstack *current_obstack; 85extern struct obstack *saveable_obstack; 86extern struct obstack *rtl_obstack; 87extern struct obstack permanent_obstack; 88#define obstack_chunk_alloc xmalloc 89 90/* Number for making the label on the next 91 constant that is stored in memory. */ 92 93int const_labelno; 94 95/* Number for making the label on the next 96 static variable internal to a function. */ 97 98int var_labelno; 99 100/* Carry information from ASM_DECLARE_OBJECT_NAME 101 to ASM_FINISH_DECLARE_OBJECT. */ 102 103int size_directive_output; 104 105/* The last decl for which assemble_variable was called, 106 if it did ASM_DECLARE_OBJECT_NAME. 107 If the last call to assemble_variable didn't do that, 108 this holds 0. */ 109 110tree last_assemble_variable_decl; 111 112/* Nonzero if at least one function definition has been seen. */ 113 114static int function_defined; 115 116struct addr_const; 117struct constant_descriptor; 118struct rtx_const; 119struct pool_constant; 120 121static const char *strip_reg_name PROTO((const char *)); 122static int contains_pointers_p PROTO((tree)); 123static void decode_addr_const PROTO((tree, struct addr_const *)); 124static int const_hash PROTO((tree)); 125static int compare_constant PROTO((tree, 126 struct constant_descriptor *)); 127static char *compare_constant_1 PROTO((tree, char *)); 128static struct constant_descriptor *record_constant PROTO((tree)); 129static void record_constant_1 PROTO((tree)); 130static tree copy_constant PROTO((tree)); 131static void output_constant_def_contents PROTO((tree, int, int)); 132static void decode_rtx_const PROTO((enum machine_mode, rtx, 133 struct rtx_const *)); 134static int const_hash_rtx PROTO((enum machine_mode, rtx)); 135static int compare_constant_rtx PROTO((enum machine_mode, rtx, 136 struct constant_descriptor *)); 137static struct constant_descriptor *record_constant_rtx PROTO((enum machine_mode, 138 rtx)); 139static struct pool_constant *find_pool_constant PROTO((rtx)); 140static void mark_constant_pool PROTO((void)); 141static void mark_constants PROTO((rtx)); 142static int output_addressed_constants PROTO((tree)); 143static void output_after_function_constants PROTO((void)); 144static void output_constructor PROTO((tree, int)); 145static void remove_from_pending_weak_list PROTO ((char *)); 146#ifdef ASM_OUTPUT_BSS 147static void asm_output_bss PROTO((FILE *, tree, char *, int, int)); 148#endif 149#ifdef BSS_SECTION_ASM_OP 150#ifdef ASM_OUTPUT_ALIGNED_BSS 151static void asm_output_aligned_bss PROTO((FILE *, tree, char *, int, int)); 152#endif 153#endif /* BSS_SECTION_ASM_OP */ 154 155static enum in_section { no_section, in_text, in_data, in_named 156#ifdef BSS_SECTION_ASM_OP 157 , in_bss 158#endif 159#ifdef EH_FRAME_SECTION_ASM_OP 160 , in_eh_frame 161#endif 162#ifdef EXTRA_SECTIONS 163 , EXTRA_SECTIONS 164#endif 165} in_section = no_section; 166 167/* Return a non-zero value if DECL has a section attribute. */ 168#define IN_NAMED_SECTION(DECL) \ 169 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \ 170 && DECL_SECTION_NAME (DECL) != NULL_TREE) 171 172/* Text of section name when in_section == in_named. */ 173static char *in_named_name; 174 175/* Define functions like text_section for any extra sections. */ 176#ifdef EXTRA_SECTION_FUNCTIONS 177EXTRA_SECTION_FUNCTIONS 178#endif 179 180/* Tell assembler to switch to text section. */ 181 182void 183text_section () 184{ 185 if (in_section != in_text) 186 { 187 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP); 188 in_section = in_text; 189 } 190} 191 192/* Tell assembler to switch to data section. */ 193 194void 195data_section () 196{ 197 if (in_section != in_data) 198 { 199 if (flag_shared_data) 200 { 201#ifdef SHARED_SECTION_ASM_OP 202 fprintf (asm_out_file, "%s\n", SHARED_SECTION_ASM_OP); 203#else 204 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP); 205#endif 206 } 207 else 208 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP); 209 210 in_section = in_data; 211 } 212} 213/* Tell assembler to ALWAYS switch to data section, in case 214 it's not sure where it it. */ 215 216void 217force_data_section () 218{ 219 in_section = no_section; 220 data_section (); 221} 222 223/* Tell assembler to switch to read-only data section. This is normally 224 the text section. */ 225 226void 227readonly_data_section () 228{ 229#ifdef READONLY_DATA_SECTION 230 READONLY_DATA_SECTION (); /* Note this can call data_section. */ 231#else 232 text_section (); 233#endif 234} 235 236/* Determine if we're in the text section. */ 237 238int 239in_text_section () 240{ 241 return in_section == in_text; 242} 243 244/* Determine if we're in the data section. */ 245 246int 247in_data_section () 248{ 249 return in_section == in_data; 250} 251 252/* Tell assembler to change to section NAME for DECL. 253 If DECL is NULL, just switch to section NAME. 254 If NAME is NULL, get the name from DECL. 255 If RELOC is 1, the initializer for DECL contains relocs. */ 256 257void 258named_section (decl, name, reloc) 259 tree decl; 260 const char *name; 261 int reloc ATTRIBUTE_UNUSED; 262{ 263 if (decl != NULL_TREE 264 && TREE_CODE_CLASS (TREE_CODE (decl)) != 'd') 265 abort (); 266 if (name == NULL) 267 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl)); 268 269 if (in_section != in_named || strcmp (name, in_named_name)) 270 { 271#ifdef ASM_OUTPUT_SECTION_NAME 272 ASM_OUTPUT_SECTION_NAME (asm_out_file, decl, name, reloc); 273#else 274 /* Section attributes are not supported if this macro isn't provided - 275 some host formats don't support them at all. The front-end should 276 already have flagged this as an error. */ 277 abort (); 278#endif 279 280 in_named_name = obstack_alloc (&permanent_obstack, strlen (name) + 1); 281 strcpy (in_named_name, name); 282 in_section = in_named; 283 } 284} 285 286#ifdef ASM_OUTPUT_SECTION_NAME 287#ifndef UNIQUE_SECTION 288#define UNIQUE_SECTION(DECL,RELOC) \ 289do { \ 290 int len; \ 291 char *name, *string; \ 292 \ 293 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (DECL)); \ 294 /* Strip off any encoding in name. */ \ 295 STRIP_NAME_ENCODING (name, name); \ 296 \ 297 len = strlen (name) + 1; \ 298 string = alloca (len + 1); \ 299 sprintf (string, ".%s", name); \ 300 \ 301 DECL_SECTION_NAME (DECL) = build_string (len, string); \ 302} while (0) 303#endif 304#ifndef UNIQUE_SECTION_P 305#define UNIQUE_SECTION_P(DECL) 0 306#endif 307#endif 308 309#ifdef BSS_SECTION_ASM_OP 310 311/* Tell the assembler to switch to the bss section. */ 312 313void 314bss_section () 315{ 316 if (in_section != in_bss) 317 { 318#ifdef SHARED_BSS_SECTION_ASM_OP 319 if (flag_shared_data) 320 fprintf (asm_out_file, "%s\n", SHARED_BSS_SECTION_ASM_OP); 321 else 322#endif 323 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP); 324 325 in_section = in_bss; 326 } 327} 328 329#ifdef ASM_OUTPUT_BSS 330 331/* Utility function for ASM_OUTPUT_BSS for targets to use if 332 they don't support alignments in .bss. 333 ??? It is believed that this function will work in most cases so such 334 support is localized here. */ 335 336static void 337asm_output_bss (file, decl, name, size, rounded) 338 FILE *file; 339 tree decl; 340 char *name; 341 int size, rounded; 342{ 343 ASM_GLOBALIZE_LABEL (file, name); 344 bss_section (); 345#ifdef ASM_DECLARE_OBJECT_NAME 346 last_assemble_variable_decl = decl; 347 ASM_DECLARE_OBJECT_NAME (file, name, decl); 348#else 349 /* Standard thing is just output label for the object. */ 350 ASM_OUTPUT_LABEL (file, name); 351#endif /* ASM_DECLARE_OBJECT_NAME */ 352 ASM_OUTPUT_SKIP (file, rounded); 353} 354 355#endif 356 357#ifdef ASM_OUTPUT_ALIGNED_BSS 358 359/* Utility function for targets to use in implementing 360 ASM_OUTPUT_ALIGNED_BSS. 361 ??? It is believed that this function will work in most cases so such 362 support is localized here. */ 363 364static void 365asm_output_aligned_bss (file, decl, name, size, align) 366 FILE *file; 367 tree decl; 368 char *name; 369 int size, align; 370{ 371 ASM_GLOBALIZE_LABEL (file, name); 372 bss_section (); 373 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT)); 374#ifdef ASM_DECLARE_OBJECT_NAME 375 last_assemble_variable_decl = decl; 376 ASM_DECLARE_OBJECT_NAME (file, name, decl); 377#else 378 /* Standard thing is just output label for the object. */ 379 ASM_OUTPUT_LABEL (file, name); 380#endif /* ASM_DECLARE_OBJECT_NAME */ 381 ASM_OUTPUT_SKIP (file, size ? size : 1); 382} 383 384#endif 385 386#endif /* BSS_SECTION_ASM_OP */ 387 388#ifdef EH_FRAME_SECTION_ASM_OP 389void 390eh_frame_section () 391{ 392 if (in_section != in_eh_frame) 393 { 394 fprintf (asm_out_file, "%s\n", EH_FRAME_SECTION_ASM_OP); 395 in_section = in_eh_frame; 396 } 397} 398#endif 399 400/* Switch to the section for function DECL. 401 402 If DECL is NULL_TREE, switch to the text section. 403 ??? It's not clear that we will ever be passed NULL_TREE, but it's 404 safer to handle it. */ 405 406void 407function_section (decl) 408 tree decl; 409{ 410 if (decl != NULL_TREE 411 && DECL_SECTION_NAME (decl) != NULL_TREE) 412 named_section (decl, (char *) 0, 0); 413 else 414 text_section (); 415} 416 417/* Switch to section for variable DECL. 418 419 RELOC is the `reloc' argument to SELECT_SECTION. */ 420 421void 422variable_section (decl, reloc) 423 tree decl; 424 int reloc; 425{ 426 if (IN_NAMED_SECTION (decl)) 427 named_section (decl, NULL, reloc); 428 else 429 { 430 /* C++ can have const variables that get initialized from constructors, 431 and thus can not be in a readonly section. We prevent this by 432 verifying that the initial value is constant for objects put in a 433 readonly section. 434 435 error_mark_node is used by the C front end to indicate that the 436 initializer has not been seen yet. In this case, we assume that 437 the initializer must be constant. 438 439 C++ uses error_mark_node for variables that have complicated 440 initializers, but these variables go in BSS so we won't be called 441 for them. */ 442 443#ifdef SELECT_SECTION 444 SELECT_SECTION (decl, reloc); 445#else 446 if (DECL_READONLY_SECTION (decl, reloc)) 447 readonly_data_section (); 448 else 449 data_section (); 450#endif 451 } 452} 453 454/* Tell assembler to switch to the section for the exception handling 455 table. */ 456 457void 458exception_section () 459{ 460#if defined (EXCEPTION_SECTION) 461 EXCEPTION_SECTION (); 462#else 463#ifdef ASM_OUTPUT_SECTION_NAME 464 named_section (NULL_TREE, ".gcc_except_table", 0); 465#else 466 if (flag_pic) 467 data_section (); 468 else 469 readonly_data_section (); 470#endif 471#endif 472} 473 474/* Create the rtl to represent a function, for a function definition. 475 DECL is a FUNCTION_DECL node which describes which function. 476 The rtl is stored into DECL. */ 477 478void 479make_function_rtl (decl) 480 tree decl; 481{ 482 char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 483 char *new_name = name; 484 485 /* Rename a nested function to avoid conflicts. */ 486 if (decl_function_context (decl) != 0 487 && DECL_INITIAL (decl) != 0 488 && DECL_RTL (decl) == 0) 489 { 490 char *label; 491 492 name = IDENTIFIER_POINTER (DECL_NAME (decl)); 493 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno); 494 name = obstack_copy0 (saveable_obstack, label, strlen (label)); 495 var_labelno++; 496 } 497 else 498 { 499 /* When -fprefix-function-name is used, every function name is 500 prefixed. Even static functions are prefixed because they 501 could be declared latter. Note that a nested function name 502 is not prefixed. */ 503 if (flag_prefix_function_name) 504 { 505 new_name = (char *) alloca (strlen (name) + CHKR_PREFIX_SIZE + 1); 506 strcpy (new_name, CHKR_PREFIX); 507 strcpy (new_name + CHKR_PREFIX_SIZE, name); 508 name = obstack_copy0 (saveable_obstack, new_name, strlen (new_name)); 509 } 510 } 511 512 if (DECL_RTL (decl) == 0) 513 { 514 DECL_RTL (decl) 515 = gen_rtx_MEM (DECL_MODE (decl), 516 gen_rtx_SYMBOL_REF (Pmode, name)); 517 518 /* Optionally set flags or add text to the name to record information 519 such as that it is a function name. If the name is changed, the macro 520 ASM_OUTPUT_LABELREF will have to know how to strip this information. */ 521#ifdef ENCODE_SECTION_INFO 522 ENCODE_SECTION_INFO (decl); 523#endif 524 } 525 else 526 { 527 /* ??? Another way to do this would be to do what halfpic.c does 528 and maintain a hashed table of such critters. */ 529 /* ??? Another way to do this would be to pass a flag bit to 530 ENCODE_SECTION_INFO saying whether this is a new decl or not. */ 531 /* Let the target reassign the RTL if it wants. 532 This is necessary, for example, when one machine specific 533 decl attribute overrides another. */ 534#ifdef REDO_SECTION_INFO_P 535 if (REDO_SECTION_INFO_P (decl)) 536 ENCODE_SECTION_INFO (decl); 537#endif 538 } 539 540 /* Record at least one function has been defined. */ 541 function_defined = 1; 542} 543 544/* Given NAME, a putative register name, discard any customary prefixes. */ 545 546static const char * 547strip_reg_name (name) 548 const char *name; 549{ 550#ifdef REGISTER_PREFIX 551 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX))) 552 name += strlen (REGISTER_PREFIX); 553#endif 554 if (name[0] == '%' || name[0] == '#') 555 name++; 556 return name; 557} 558 559/* Decode an `asm' spec for a declaration as a register name. 560 Return the register number, or -1 if nothing specified, 561 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized, 562 or -3 if ASMSPEC is `cc' and is not recognized, 563 or -4 if ASMSPEC is `memory' and is not recognized. 564 Accept an exact spelling or a decimal number. 565 Prefixes such as % are optional. */ 566 567int 568decode_reg_name (asmspec) 569 const char *asmspec; 570{ 571 if (asmspec != 0) 572 { 573 int i; 574 575 /* Get rid of confusing prefixes. */ 576 asmspec = strip_reg_name (asmspec); 577 578 /* Allow a decimal number as a "register name". */ 579 for (i = strlen (asmspec) - 1; i >= 0; i--) 580 if (! (asmspec[i] >= '0' && asmspec[i] <= '9')) 581 break; 582 if (asmspec[0] != 0 && i < 0) 583 { 584 i = atoi (asmspec); 585 if (i < FIRST_PSEUDO_REGISTER && i >= 0) 586 return i; 587 else 588 return -2; 589 } 590 591 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) 592 if (reg_names[i][0] 593 && ! strcmp (asmspec, strip_reg_name (reg_names[i]))) 594 return i; 595 596#ifdef ADDITIONAL_REGISTER_NAMES 597 { 598 static struct { const char *name; int number; } table[] 599 = ADDITIONAL_REGISTER_NAMES; 600 601 for (i = 0; i < (int)(sizeof (table) / sizeof (table[0])); i++) 602 if (! strcmp (asmspec, table[i].name)) 603 return table[i].number; 604 } 605#endif /* ADDITIONAL_REGISTER_NAMES */ 606 607 if (!strcmp (asmspec, "memory")) 608 return -4; 609 610 if (!strcmp (asmspec, "cc")) 611 return -3; 612 613 return -2; 614 } 615 616 return -1; 617} 618 619/* Create the DECL_RTL for a declaration for a static or external variable 620 or static or external function. 621 ASMSPEC, if not 0, is the string which the user specified 622 as the assembler symbol name. 623 TOP_LEVEL is nonzero if this is a file-scope variable. 624 625 This is never called for PARM_DECL nodes. */ 626 627void 628make_decl_rtl (decl, asmspec, top_level) 629 tree decl; 630 const char *asmspec; 631 int top_level; 632{ 633 register char *name = 0; 634 int reg_number; 635 636 reg_number = decode_reg_name (asmspec); 637 638 if (DECL_ASSEMBLER_NAME (decl) != NULL_TREE) 639 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 640 641 if (reg_number == -2) 642 { 643 /* ASMSPEC is given, and not the name of a register. */ 644 name = (char *) obstack_alloc (saveable_obstack, 645 strlen (asmspec) + 2); 646 name[0] = '*'; 647 strcpy (&name[1], asmspec); 648 } 649 650 /* For a duplicate declaration, we can be called twice on the 651 same DECL node. Don't discard the RTL already made. */ 652 if (DECL_RTL (decl) == 0) 653 { 654 /* First detect errors in declaring global registers. */ 655 if (TREE_CODE (decl) != FUNCTION_DECL 656 && DECL_REGISTER (decl) && reg_number == -1) 657 error_with_decl (decl, 658 "register name not specified for `%s'"); 659 else if (TREE_CODE (decl) != FUNCTION_DECL 660 && DECL_REGISTER (decl) && reg_number < 0) 661 error_with_decl (decl, 662 "invalid register name for `%s'"); 663 else if ((reg_number >= 0 || reg_number == -3) 664 && (TREE_CODE (decl) == FUNCTION_DECL 665 && ! DECL_REGISTER (decl))) 666 error_with_decl (decl, 667 "register name given for non-register variable `%s'"); 668 else if (TREE_CODE (decl) != FUNCTION_DECL 669 && DECL_REGISTER (decl) 670 && TYPE_MODE (TREE_TYPE (decl)) == BLKmode) 671 error_with_decl (decl, 672 "data type of `%s' isn't suitable for a register"); 673 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl) 674 && ! HARD_REGNO_MODE_OK (reg_number, 675 TYPE_MODE (TREE_TYPE (decl)))) 676 error_with_decl (decl, 677 "register number for `%s' isn't suitable for data type"); 678 /* Now handle properly declared static register variables. */ 679 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl)) 680 { 681 int nregs; 682 683 if (DECL_INITIAL (decl) != 0 && top_level) 684 { 685 DECL_INITIAL (decl) = 0; 686 error ("global register variable has initial value"); 687 } 688 if (fixed_regs[reg_number] == 0 689 && function_defined && top_level) 690 error ("global register variable follows a function definition"); 691 if (TREE_THIS_VOLATILE (decl)) 692 warning ("volatile register variables don't work as you might wish"); 693 694 /* If the user specified one of the eliminables registers here, 695 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable 696 confused with that register and be eliminated. Although this 697 usage is somewhat suspect, we nevertheless use the following 698 kludge to avoid setting DECL_RTL to frame_pointer_rtx. */ 699 700 DECL_RTL (decl) 701 = gen_rtx_REG (DECL_MODE (decl), FIRST_PSEUDO_REGISTER); 702 REGNO (DECL_RTL (decl)) = reg_number; 703 REG_USERVAR_P (DECL_RTL (decl)) = 1; 704 705 if (top_level) 706 { 707 /* Make this register global, so not usable for anything 708 else. */ 709 nregs = HARD_REGNO_NREGS (reg_number, DECL_MODE (decl)); 710 while (nregs > 0) 711 globalize_reg (reg_number + --nregs); 712 } 713 } 714 /* Specifying a section attribute on a variable forces it into a 715 non-.bss section, and thus it cannot be common. */ 716 else if (TREE_CODE (decl) == VAR_DECL 717 && DECL_SECTION_NAME (decl) != NULL_TREE 718 && DECL_INITIAL (decl) == NULL_TREE 719 && DECL_COMMON (decl)) 720 DECL_COMMON (decl) = 0; 721 722 /* Now handle ordinary static variables and functions (in memory). 723 Also handle vars declared register invalidly. */ 724 if (DECL_RTL (decl) == 0) 725 { 726 /* Can't use just the variable's own name for a variable 727 whose scope is less than the whole file. 728 Concatenate a distinguishing number. */ 729 if (!top_level && !TREE_PUBLIC (decl) && asmspec == 0) 730 { 731 char *label; 732 733 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno); 734 name = obstack_copy0 (saveable_obstack, label, strlen (label)); 735 var_labelno++; 736 } 737 738 if (name == 0) 739 abort (); 740 741 /* When -fprefix-function-name is used, the functions 742 names are prefixed. Only nested function names are not 743 prefixed. */ 744 if (flag_prefix_function_name && TREE_CODE (decl) == FUNCTION_DECL) 745 { 746 char *new_name; 747 new_name = (char *) alloca (strlen (name) + CHKR_PREFIX_SIZE 748 + 1); 749 strcpy (new_name, CHKR_PREFIX); 750 strcpy (new_name + CHKR_PREFIX_SIZE, name); 751 name = obstack_copy0 (saveable_obstack, 752 new_name, strlen (new_name)); 753 } 754 755 DECL_RTL (decl) = gen_rtx_MEM (DECL_MODE (decl), 756 gen_rtx_SYMBOL_REF (Pmode, name)); 757 MEM_ALIAS_SET (DECL_RTL (decl)) = get_alias_set (decl); 758 759 /* If this variable is to be treated as volatile, show its 760 tree node has side effects. If it has side effects, either 761 because of this test or from TREE_THIS_VOLATILE also 762 being set, show the MEM is volatile. */ 763 if (flag_volatile_global && TREE_CODE (decl) == VAR_DECL 764 && TREE_PUBLIC (decl)) 765 TREE_SIDE_EFFECTS (decl) = 1; 766 else if (flag_volatile_static && TREE_CODE (decl) == VAR_DECL 767 && (TREE_PUBLIC (decl) || TREE_STATIC (decl))) 768 TREE_SIDE_EFFECTS (decl) = 1; 769 770 if (TREE_SIDE_EFFECTS (decl)) 771 MEM_VOLATILE_P (DECL_RTL (decl)) = 1; 772 773 if (TREE_READONLY (decl)) 774 RTX_UNCHANGING_P (DECL_RTL (decl)) = 1; 775 MEM_SET_IN_STRUCT_P (DECL_RTL (decl), 776 AGGREGATE_TYPE_P (TREE_TYPE (decl))); 777 778 /* Optionally set flags or add text to the name to record information 779 such as that it is a function name. 780 If the name is changed, the macro ASM_OUTPUT_LABELREF 781 will have to know how to strip this information. */ 782#ifdef ENCODE_SECTION_INFO 783 ENCODE_SECTION_INFO (decl); 784#endif 785 } 786 } 787 else 788 { 789 /* If the old RTL had the wrong mode, fix the mode. */ 790 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl)) 791 { 792 rtx rtl = DECL_RTL (decl); 793 PUT_MODE (rtl, DECL_MODE (decl)); 794 } 795 796 /* ??? Another way to do this would be to do what halfpic.c does 797 and maintain a hashed table of such critters. */ 798 /* ??? Another way to do this would be to pass a flag bit to 799 ENCODE_SECTION_INFO saying whether this is a new decl or not. */ 800 /* Let the target reassign the RTL if it wants. 801 This is necessary, for example, when one machine specific 802 decl attribute overrides another. */ 803#ifdef REDO_SECTION_INFO_P 804 if (REDO_SECTION_INFO_P (decl)) 805 ENCODE_SECTION_INFO (decl); 806#endif 807 } 808} 809 810/* Make the rtl for variable VAR be volatile. 811 Use this only for static variables. */ 812 813void 814make_var_volatile (var) 815 tree var; 816{ 817 if (GET_CODE (DECL_RTL (var)) != MEM) 818 abort (); 819 820 MEM_VOLATILE_P (DECL_RTL (var)) = 1; 821} 822 823/* Output alignment directive to align for constant expression EXP. */ 824 825void 826assemble_constant_align (exp) 827 tree exp; 828{ 829 int align; 830 831 /* Align the location counter as required by EXP's data type. */ 832 align = TYPE_ALIGN (TREE_TYPE (exp)); 833#ifdef CONSTANT_ALIGNMENT 834 align = CONSTANT_ALIGNMENT (exp, align); 835#endif 836 837 if (align > BITS_PER_UNIT) 838 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 839} 840 841/* Output a string of literal assembler code 842 for an `asm' keyword used between functions. */ 843 844void 845assemble_asm (string) 846 tree string; 847{ 848 app_enable (); 849 850 if (TREE_CODE (string) == ADDR_EXPR) 851 string = TREE_OPERAND (string, 0); 852 853 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string)); 854} 855 856#if 0 /* This should no longer be needed, because 857 flag_gnu_linker should be 0 on these systems, 858 which should prevent any output 859 if ASM_OUTPUT_CONSTRUCTOR and ASM_OUTPUT_DESTRUCTOR are absent. */ 860#if !(defined(DBX_DEBUGGING_INFO) && !defined(FASCIST_ASSEMBLER)) 861#ifndef ASM_OUTPUT_CONSTRUCTOR 862#define ASM_OUTPUT_CONSTRUCTOR(file, name) 863#endif 864#ifndef ASM_OUTPUT_DESTRUCTOR 865#define ASM_OUTPUT_DESTRUCTOR(file, name) 866#endif 867#endif 868#endif /* 0 */ 869 870/* Record an element in the table of global destructors. 871 How this is done depends on what sort of assembler and linker 872 are in use. 873 874 NAME should be the name of a global function to be called 875 at exit time. This name is output using assemble_name. */ 876 877void 878assemble_destructor (name) 879 char *name; 880{ 881#ifdef ASM_OUTPUT_DESTRUCTOR 882 ASM_OUTPUT_DESTRUCTOR (asm_out_file, name); 883#else 884 if (flag_gnu_linker) 885 { 886 /* Now tell GNU LD that this is part of the static destructor set. */ 887 /* This code works for any machine provided you use GNU as/ld. */ 888 fprintf (asm_out_file, "%s \"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP); 889 assemble_name (asm_out_file, name); 890 fputc ('\n', asm_out_file); 891 } 892#endif 893} 894 895/* Likewise for global constructors. */ 896 897void 898assemble_constructor (name) 899 char *name; 900{ 901#ifdef ASM_OUTPUT_CONSTRUCTOR 902 ASM_OUTPUT_CONSTRUCTOR (asm_out_file, name); 903#else 904 if (flag_gnu_linker) 905 { 906 /* Now tell GNU LD that this is part of the static constructor set. */ 907 /* This code works for any machine provided you use GNU as/ld. */ 908 fprintf (asm_out_file, "%s \"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP); 909 assemble_name (asm_out_file, name); 910 fputc ('\n', asm_out_file); 911 } 912#endif 913} 914 915/* Likewise for entries we want to record for garbage collection. 916 Garbage collection is still under development. */ 917 918void 919assemble_gc_entry (name) 920 char *name; 921{ 922#ifdef ASM_OUTPUT_GC_ENTRY 923 ASM_OUTPUT_GC_ENTRY (asm_out_file, name); 924#else 925 if (flag_gnu_linker) 926 { 927 /* Now tell GNU LD that this is part of the static constructor set. */ 928 fprintf (asm_out_file, "%s \"___PTR_LIST__\",22,0,0,", ASM_STABS_OP); 929 assemble_name (asm_out_file, name); 930 fputc ('\n', asm_out_file); 931 } 932#endif 933} 934 935/* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with 936 a non-zero value if the constant pool should be output before the 937 start of the function, or a zero value if the pool should output 938 after the end of the function. The default is to put it before the 939 start. */ 940 941#ifndef CONSTANT_POOL_BEFORE_FUNCTION 942#define CONSTANT_POOL_BEFORE_FUNCTION 1 943#endif 944 945/* Output assembler code for the constant pool of a function and associated 946 with defining the name of the function. DECL describes the function. 947 NAME is the function's name. For the constant pool, we use the current 948 constant pool data. */ 949 950void 951assemble_start_function (decl, fnname) 952 tree decl; 953 char *fnname; 954{ 955 int align; 956 957 /* The following code does not need preprocessing in the assembler. */ 958 959 app_disable (); 960 961 if (CONSTANT_POOL_BEFORE_FUNCTION) 962 output_constant_pool (fnname, decl); 963 964#ifdef ASM_OUTPUT_SECTION_NAME 965 /* If the function is to be put in its own section and it's not in a section 966 already, indicate so. */ 967 if ((flag_function_sections 968 && DECL_SECTION_NAME (decl) == NULL_TREE) 969 || UNIQUE_SECTION_P (decl)) 970 UNIQUE_SECTION (decl, 0); 971#endif 972 973 function_section (decl); 974 975 /* Tell assembler to move to target machine's alignment for functions. */ 976 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT); 977 if (align > 0) 978 ASM_OUTPUT_ALIGN (asm_out_file, align); 979 980#ifdef ASM_OUTPUT_FUNCTION_PREFIX 981 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname); 982#endif 983 984#ifdef SDB_DEBUGGING_INFO 985 /* Output SDB definition of the function. */ 986 if (write_symbols == SDB_DEBUG) 987 sdbout_mark_begin_function (); 988#endif 989 990#ifdef DBX_DEBUGGING_INFO 991 /* Output DBX definition of the function. */ 992 if (write_symbols == DBX_DEBUG) 993 dbxout_begin_function (decl); 994#endif 995 996 /* Make function name accessible from other files, if appropriate. */ 997 998 if (TREE_PUBLIC (decl)) 999 { 1000 if (! first_global_object_name) 1001 { 1002 char *p; 1003 char **name; 1004 1005 if (! DECL_WEAK (decl) && ! DECL_ONE_ONLY (decl)) 1006 name = &first_global_object_name; 1007 else 1008 name = &weak_global_object_name; 1009 1010 STRIP_NAME_ENCODING (p, fnname); 1011 *name = permalloc (strlen (p) + 1); 1012 strcpy (*name, p); 1013 } 1014 1015#ifdef ASM_WEAKEN_LABEL 1016 if (DECL_WEAK (decl)) 1017 { 1018 ASM_WEAKEN_LABEL (asm_out_file, fnname); 1019 /* Remove this function from the pending weak list so that 1020 we do not emit multiple .weak directives for it. */ 1021 remove_from_pending_weak_list 1022 (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl))); 1023 } 1024 else 1025#endif 1026 ASM_GLOBALIZE_LABEL (asm_out_file, fnname); 1027 } 1028 1029 /* Do any machine/system dependent processing of the function name */ 1030#ifdef ASM_DECLARE_FUNCTION_NAME 1031 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl); 1032#else 1033 /* Standard thing is just output label for the function. */ 1034 ASM_OUTPUT_LABEL (asm_out_file, fnname); 1035#endif /* ASM_DECLARE_FUNCTION_NAME */ 1036} 1037 1038/* Output assembler code associated with defining the size of the 1039 function. DECL describes the function. NAME is the function's name. */ 1040 1041void 1042assemble_end_function (decl, fnname) 1043 tree decl; 1044 char *fnname; 1045{ 1046#ifdef ASM_DECLARE_FUNCTION_SIZE 1047 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl); 1048#endif 1049 if (! CONSTANT_POOL_BEFORE_FUNCTION) 1050 { 1051 output_constant_pool (fnname, decl); 1052 function_section (decl); /* need to switch back */ 1053 } 1054 1055 /* Output any constants which should appear after the function. */ 1056 output_after_function_constants (); 1057} 1058 1059/* Assemble code to leave SIZE bytes of zeros. */ 1060 1061void 1062assemble_zeros (size) 1063 int size; 1064{ 1065 /* Do no output if -fsyntax-only. */ 1066 if (flag_syntax_only) 1067 return; 1068 1069#ifdef ASM_NO_SKIP_IN_TEXT 1070 /* The `space' pseudo in the text section outputs nop insns rather than 0s, 1071 so we must output 0s explicitly in the text section. */ 1072 if (ASM_NO_SKIP_IN_TEXT && in_text_section ()) 1073 { 1074 int i; 1075 1076 for (i = 0; i < size - 20; i += 20) 1077 { 1078#ifdef ASM_BYTE_OP 1079 fprintf (asm_out_file, 1080 "%s 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0\n", ASM_BYTE_OP); 1081#else 1082 fprintf (asm_out_file, 1083 "\tbyte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0\n"); 1084#endif 1085 } 1086 if (i < size) 1087 { 1088#ifdef ASM_BYTE_OP 1089 fprintf (asm_out_file, "%s 0", ASM_BYTE_OP); 1090#else 1091 fprintf (asm_out_file, "\tbyte 0"); 1092#endif 1093 i++; 1094 for (; i < size; i++) 1095 fprintf (asm_out_file, ",0"); 1096 fprintf (asm_out_file, "\n"); 1097 } 1098 } 1099 else 1100#endif 1101 if (size > 0) 1102 ASM_OUTPUT_SKIP (asm_out_file, size); 1103} 1104 1105/* Assemble an alignment pseudo op for an ALIGN-bit boundary. */ 1106 1107void 1108assemble_align (align) 1109 int align; 1110{ 1111 if (align > BITS_PER_UNIT) 1112 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 1113} 1114 1115/* Assemble a string constant with the specified C string as contents. */ 1116 1117void 1118assemble_string (p, size) 1119 const char *p; 1120 int size; 1121{ 1122 int pos = 0; 1123 int maximum = 2000; 1124 1125 /* If the string is very long, split it up. */ 1126 1127 while (pos < size) 1128 { 1129 int thissize = size - pos; 1130 if (thissize > maximum) 1131 thissize = maximum; 1132 1133 ASM_OUTPUT_ASCII (asm_out_file, p, thissize); 1134 1135 pos += thissize; 1136 p += thissize; 1137 } 1138} 1139 1140 1141/* Assemble everything that is needed for a variable or function declaration. 1142 Not used for automatic variables, and not used for function definitions. 1143 Should not be called for variables of incomplete structure type. 1144 1145 TOP_LEVEL is nonzero if this variable has file scope. 1146 AT_END is nonzero if this is the special handling, at end of compilation, 1147 to define things that have had only tentative definitions. 1148 DONT_OUTPUT_DATA if nonzero means don't actually output the 1149 initial value (that will be done by the caller). */ 1150 1151void 1152assemble_variable (decl, top_level, at_end, dont_output_data) 1153 tree decl; 1154 int top_level ATTRIBUTE_UNUSED; 1155 int at_end; 1156 int dont_output_data; 1157{ 1158 register char *name; 1159 unsigned int align; 1160 tree size_tree; 1161 int reloc = 0; 1162 enum in_section saved_in_section; 1163 1164 last_assemble_variable_decl = 0; 1165 1166 if (GET_CODE (DECL_RTL (decl)) == REG) 1167 { 1168 /* Do output symbol info for global register variables, but do nothing 1169 else for them. */ 1170 1171 if (TREE_ASM_WRITTEN (decl)) 1172 return; 1173 TREE_ASM_WRITTEN (decl) = 1; 1174 1175 /* Do no output if -fsyntax-only. */ 1176 if (flag_syntax_only) 1177 return; 1178 1179#if defined (DBX_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO) 1180 /* File-scope global variables are output here. */ 1181 if ((write_symbols == DBX_DEBUG || write_symbols == XCOFF_DEBUG) 1182 && top_level) 1183 dbxout_symbol (decl, 0); 1184#endif 1185#ifdef SDB_DEBUGGING_INFO 1186 if (write_symbols == SDB_DEBUG && top_level 1187 /* Leave initialized global vars for end of compilation; 1188 see comment in compile_file. */ 1189 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0)) 1190 sdbout_symbol (decl, 0); 1191#endif 1192 1193 /* Don't output any DWARF debugging information for variables here. 1194 In the case of local variables, the information for them is output 1195 when we do our recursive traversal of the tree representation for 1196 the entire containing function. In the case of file-scope variables, 1197 we output information for all of them at the very end of compilation 1198 while we are doing our final traversal of the chain of file-scope 1199 declarations. */ 1200 1201 return; 1202 } 1203 1204 /* Normally no need to say anything here for external references, 1205 since assemble_external is called by the language-specific code 1206 when a declaration is first seen. */ 1207 1208 if (DECL_EXTERNAL (decl)) 1209 return; 1210 1211 /* Output no assembler code for a function declaration. 1212 Only definitions of functions output anything. */ 1213 1214 if (TREE_CODE (decl) == FUNCTION_DECL) 1215 return; 1216 1217 /* If type was incomplete when the variable was declared, 1218 see if it is complete now. */ 1219 1220 if (DECL_SIZE (decl) == 0) 1221 layout_decl (decl, 0); 1222 1223 /* Still incomplete => don't allocate it; treat the tentative defn 1224 (which is what it must have been) as an `extern' reference. */ 1225 1226 if (!dont_output_data && DECL_SIZE (decl) == 0) 1227 { 1228 error_with_file_and_line (DECL_SOURCE_FILE (decl), 1229 DECL_SOURCE_LINE (decl), 1230 "storage size of `%s' isn't known", 1231 IDENTIFIER_POINTER (DECL_NAME (decl))); 1232 TREE_ASM_WRITTEN (decl) = 1; 1233 return; 1234 } 1235 1236 /* The first declaration of a variable that comes through this function 1237 decides whether it is global (in C, has external linkage) 1238 or local (in C, has internal linkage). So do nothing more 1239 if this function has already run. */ 1240 1241 if (TREE_ASM_WRITTEN (decl)) 1242 return; 1243 1244 TREE_ASM_WRITTEN (decl) = 1; 1245 1246 /* Do no output if -fsyntax-only. */ 1247 if (flag_syntax_only) 1248 return; 1249 1250 app_disable (); 1251 1252 if (! dont_output_data) 1253 { 1254 int size; 1255 1256 if (TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST) 1257 goto finish; 1258 1259 /* This is better than explicit arithmetic, since it avoids overflow. */ 1260 size_tree = size_binop (CEIL_DIV_EXPR, 1261 DECL_SIZE (decl), size_int (BITS_PER_UNIT)); 1262 1263 size = TREE_INT_CST_LOW (size_tree); 1264 if (TREE_INT_CST_HIGH (size_tree) != 0 1265 || size != TREE_INT_CST_LOW (size_tree)) 1266 { 1267 error_with_decl (decl, "size of variable `%s' is too large"); 1268 goto finish; 1269 } 1270 } 1271 1272 name = XSTR (XEXP (DECL_RTL (decl), 0), 0); 1273 1274 if (TREE_PUBLIC (decl) && DECL_NAME (decl) 1275 && ! first_global_object_name 1276 && ! (DECL_COMMON (decl) && (DECL_INITIAL (decl) == 0 1277 || DECL_INITIAL (decl) == error_mark_node)) 1278 && ! DECL_WEAK (decl) 1279 && ! DECL_ONE_ONLY (decl)) 1280 { 1281 char *p; 1282 1283 STRIP_NAME_ENCODING (p, name); 1284 first_global_object_name = permalloc (strlen (p) + 1); 1285 strcpy (first_global_object_name, p); 1286 } 1287 1288 /* Compute the alignment of this data. */ 1289 1290 align = DECL_ALIGN (decl); 1291 1292 /* In the case for initialing an array whose length isn't specified, 1293 where we have not yet been able to do the layout, 1294 figure out the proper alignment now. */ 1295 if (dont_output_data && DECL_SIZE (decl) == 0 1296 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE) 1297 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl)))); 1298 1299 /* Some object file formats have a maximum alignment which they support. 1300 In particular, a.out format supports a maximum alignment of 4. */ 1301#ifndef MAX_OFILE_ALIGNMENT 1302#define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT 1303#endif 1304 if (align > MAX_OFILE_ALIGNMENT) 1305 { 1306 warning_with_decl (decl, 1307 "alignment of `%s' is greater than maximum object file alignment. Using %d.", 1308 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT); 1309 align = MAX_OFILE_ALIGNMENT; 1310 } 1311 1312 /* On some machines, it is good to increase alignment sometimes. */ 1313#ifdef DATA_ALIGNMENT 1314 align = DATA_ALIGNMENT (TREE_TYPE (decl), align); 1315#endif 1316#ifdef CONSTANT_ALIGNMENT 1317 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node) 1318 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align); 1319#endif 1320 1321 /* Reset the alignment in case we have made it tighter, so we can benefit 1322 from it in get_pointer_alignment. */ 1323 DECL_ALIGN (decl) = align; 1324 1325 /* Handle uninitialized definitions. */ 1326 1327 if ((DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node) 1328 /* If the target can't output uninitialized but not common global data 1329 in .bss, then we have to use .data. */ 1330#if ! defined (ASM_OUTPUT_BSS) && ! defined (ASM_OUTPUT_ALIGNED_BSS) 1331 && DECL_COMMON (decl) 1332#endif 1333 && DECL_SECTION_NAME (decl) == 0 1334 && ! dont_output_data) 1335 { 1336 int size = TREE_INT_CST_LOW (size_tree); 1337 int rounded = size; 1338 1339 /* Don't allocate zero bytes of common, 1340 since that means "undefined external" in the linker. */ 1341 if (size == 0) rounded = 1; 1342 /* Round size up to multiple of BIGGEST_ALIGNMENT bits 1343 so that each uninitialized object starts on such a boundary. */ 1344 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1; 1345 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) 1346 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); 1347 1348#if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS) 1349 if ( (DECL_ALIGN (decl) / BITS_PER_UNIT) > rounded) 1350 warning_with_decl 1351 (decl, "requested alignment for %s is greater than implemented alignment of %d.",rounded); 1352#endif 1353 1354#ifdef DBX_DEBUGGING_INFO 1355 /* File-scope global variables are output here. */ 1356 if (write_symbols == DBX_DEBUG && top_level) 1357 dbxout_symbol (decl, 0); 1358#endif 1359#ifdef SDB_DEBUGGING_INFO 1360 if (write_symbols == SDB_DEBUG && top_level 1361 /* Leave initialized global vars for end of compilation; 1362 see comment in compile_file. */ 1363 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0)) 1364 sdbout_symbol (decl, 0); 1365#endif 1366 1367 /* Don't output any DWARF debugging information for variables here. 1368 In the case of local variables, the information for them is output 1369 when we do our recursive traversal of the tree representation for 1370 the entire containing function. In the case of file-scope variables, 1371 we output information for all of them at the very end of compilation 1372 while we are doing our final traversal of the chain of file-scope 1373 declarations. */ 1374 1375#if 0 /* ??? We should either delete this or add a comment describing what 1376 it was intended to do and why we shouldn't delete it. */ 1377 if (flag_shared_data) 1378 data_section (); 1379#endif 1380 1381 if (TREE_PUBLIC (decl) 1382#if defined (ASM_OUTPUT_BSS) || defined (ASM_OUTPUT_ALIGNED_BSS) 1383 && DECL_COMMON (decl) 1384#endif 1385 ) 1386 { 1387#ifdef ASM_OUTPUT_SHARED_COMMON 1388 if (flag_shared_data) 1389 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded); 1390 else 1391#endif 1392 { 1393#ifdef ASM_OUTPUT_ALIGNED_DECL_COMMON 1394 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, 1395 DECL_ALIGN (decl)); 1396#else 1397#ifdef ASM_OUTPUT_ALIGNED_COMMON 1398 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, 1399 DECL_ALIGN (decl)); 1400#else 1401 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded); 1402#endif 1403#endif 1404 } 1405 } 1406#if defined (ASM_OUTPUT_BSS) || defined (ASM_OUTPUT_ALIGNED_BSS) 1407 else if (TREE_PUBLIC (decl)) 1408 { 1409#ifdef ASM_OUTPUT_SHARED_BSS 1410 if (flag_shared_data) 1411 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded); 1412 else 1413#endif 1414 { 1415#ifdef ASM_OUTPUT_ALIGNED_BSS 1416 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, 1417 DECL_ALIGN (decl)); 1418#else 1419 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded); 1420#endif 1421 } 1422 } 1423#endif /* ASM_OUTPUT_BSS || ASM_OUTPUT_ALIGNED_BSS */ 1424 else 1425 { 1426#ifdef ASM_OUTPUT_SHARED_LOCAL 1427 if (flag_shared_data) 1428 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded); 1429 else 1430#endif 1431 { 1432#ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL 1433 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, 1434 DECL_ALIGN (decl)); 1435#else 1436#ifdef ASM_OUTPUT_ALIGNED_LOCAL 1437 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, 1438 DECL_ALIGN (decl)); 1439#else 1440 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); 1441#endif 1442#endif 1443 } 1444 } 1445 goto finish; 1446 } 1447 1448 /* Handle initialized definitions. 1449 Also handle uninitialized global definitions if -fno-common and the 1450 target doesn't support ASM_OUTPUT_BSS. */ 1451 1452 /* First make the assembler name(s) global if appropriate. */ 1453 if (TREE_PUBLIC (decl) && DECL_NAME (decl)) 1454 { 1455#ifdef ASM_WEAKEN_LABEL 1456 if (DECL_WEAK (decl)) 1457 { 1458 ASM_WEAKEN_LABEL (asm_out_file, name); 1459 /* Remove this variable from the pending weak list so that 1460 we do not emit multiple .weak directives for it. */ 1461 remove_from_pending_weak_list 1462 (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl))); 1463 } 1464 else 1465#endif 1466 ASM_GLOBALIZE_LABEL (asm_out_file, name); 1467 } 1468#if 0 1469 for (d = equivalents; d; d = TREE_CHAIN (d)) 1470 { 1471 tree e = TREE_VALUE (d); 1472 if (TREE_PUBLIC (e) && DECL_NAME (e)) 1473 ASM_GLOBALIZE_LABEL (asm_out_file, 1474 XSTR (XEXP (DECL_RTL (e), 0), 0)); 1475 } 1476#endif 1477 1478 /* Output any data that we will need to use the address of. */ 1479 if (DECL_INITIAL (decl) == error_mark_node) 1480 reloc = contains_pointers_p (TREE_TYPE (decl)); 1481 else if (DECL_INITIAL (decl)) 1482 reloc = output_addressed_constants (DECL_INITIAL (decl)); 1483 1484#ifdef ASM_OUTPUT_SECTION_NAME 1485 if ((flag_data_sections != 0 1486 && DECL_SECTION_NAME (decl) == NULL_TREE) 1487 || UNIQUE_SECTION_P (decl)) 1488 UNIQUE_SECTION (decl, reloc); 1489#endif 1490 1491 /* Switch to the appropriate section. */ 1492 variable_section (decl, reloc); 1493 1494 /* dbxout.c needs to know this. */ 1495 if (in_text_section ()) 1496 DECL_IN_TEXT_SECTION (decl) = 1; 1497 1498 /* Record current section so we can restore it if dbxout.c clobbers it. */ 1499 saved_in_section = in_section; 1500 1501 /* Output the dbx info now that we have chosen the section. */ 1502 1503#ifdef DBX_DEBUGGING_INFO 1504 /* File-scope global variables are output here. */ 1505 if (write_symbols == DBX_DEBUG && top_level) 1506 dbxout_symbol (decl, 0); 1507#endif 1508#ifdef SDB_DEBUGGING_INFO 1509 if (write_symbols == SDB_DEBUG && top_level 1510 /* Leave initialized global vars for end of compilation; 1511 see comment in compile_file. */ 1512 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0)) 1513 sdbout_symbol (decl, 0); 1514#endif 1515 1516 /* Don't output any DWARF debugging information for variables here. 1517 In the case of local variables, the information for them is output 1518 when we do our recursive traversal of the tree representation for 1519 the entire containing function. In the case of file-scope variables, 1520 we output information for all of them at the very end of compilation 1521 while we are doing our final traversal of the chain of file-scope 1522 declarations. */ 1523 1524 /* If the debugging output changed sections, reselect the section 1525 that's supposed to be selected. */ 1526 if (in_section != saved_in_section) 1527 variable_section (decl, reloc); 1528 1529 /* Output the alignment of this data. */ 1530 if (align > BITS_PER_UNIT) 1531 ASM_OUTPUT_ALIGN (asm_out_file, 1532 floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT)); 1533 1534 /* Do any machine/system dependent processing of the object. */ 1535#ifdef ASM_DECLARE_OBJECT_NAME 1536 last_assemble_variable_decl = decl; 1537 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl); 1538#else 1539 /* Standard thing is just output label for the object. */ 1540 ASM_OUTPUT_LABEL (asm_out_file, name); 1541#endif /* ASM_DECLARE_OBJECT_NAME */ 1542 1543 if (!dont_output_data) 1544 { 1545 if (DECL_INITIAL (decl)) 1546 /* Output the actual data. */ 1547 output_constant (DECL_INITIAL (decl), TREE_INT_CST_LOW (size_tree)); 1548 else 1549 /* Leave space for it. */ 1550 assemble_zeros (TREE_INT_CST_LOW (size_tree)); 1551 } 1552 1553 finish: 1554#ifdef XCOFF_DEBUGGING_INFO 1555 /* Unfortunately, the IBM assembler cannot handle stabx before the actual 1556 declaration. When something like ".stabx "aa:S-2",aa,133,0" is emitted 1557 and `aa' hasn't been output yet, the assembler generates a stab entry with 1558 a value of zero, in addition to creating an unnecessary external entry 1559 for `aa'. Hence, we must postpone dbxout_symbol to here at the end. */ 1560 1561 /* File-scope global variables are output here. */ 1562 if (write_symbols == XCOFF_DEBUG && top_level) 1563 { 1564 saved_in_section = in_section; 1565 1566 dbxout_symbol (decl, 0); 1567 1568 if (in_section != saved_in_section) 1569 variable_section (decl, reloc); 1570 } 1571#else 1572 /* There must be a statement after a label. */ 1573 ; 1574#endif 1575} 1576 1577/* Return 1 if type TYPE contains any pointers. */ 1578 1579static int 1580contains_pointers_p (type) 1581 tree type; 1582{ 1583 switch (TREE_CODE (type)) 1584 { 1585 case POINTER_TYPE: 1586 case REFERENCE_TYPE: 1587 /* I'm not sure whether OFFSET_TYPE needs this treatment, 1588 so I'll play safe and return 1. */ 1589 case OFFSET_TYPE: 1590 return 1; 1591 1592 case RECORD_TYPE: 1593 case UNION_TYPE: 1594 case QUAL_UNION_TYPE: 1595 { 1596 tree fields; 1597 /* For a type that has fields, see if the fields have pointers. */ 1598 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields)) 1599 if (TREE_CODE (fields) == FIELD_DECL 1600 && contains_pointers_p (TREE_TYPE (fields))) 1601 return 1; 1602 return 0; 1603 } 1604 1605 case ARRAY_TYPE: 1606 /* An array type contains pointers if its element type does. */ 1607 return contains_pointers_p (TREE_TYPE (type)); 1608 1609 default: 1610 return 0; 1611 } 1612} 1613 1614/* Output something to declare an external symbol to the assembler. 1615 (Most assemblers don't need this, so we normally output nothing.) 1616 Do nothing if DECL is not external. */ 1617 1618void 1619assemble_external (decl) 1620 tree decl ATTRIBUTE_UNUSED; 1621{ 1622#ifdef ASM_OUTPUT_EXTERNAL 1623 if (TREE_CODE_CLASS (TREE_CODE (decl)) == 'd' 1624 && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl)) 1625 { 1626 rtx rtl = DECL_RTL (decl); 1627 1628 if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF 1629 && ! SYMBOL_REF_USED (XEXP (rtl, 0))) 1630 { 1631 /* Some systems do require some output. */ 1632 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1; 1633 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0)); 1634 } 1635 } 1636#endif 1637} 1638 1639/* Similar, for calling a library function FUN. */ 1640 1641void 1642assemble_external_libcall (fun) 1643 rtx fun ATTRIBUTE_UNUSED; 1644{ 1645#ifdef ASM_OUTPUT_EXTERNAL_LIBCALL 1646 /* Declare library function name external when first used, if nec. */ 1647 if (! SYMBOL_REF_USED (fun)) 1648 { 1649 SYMBOL_REF_USED (fun) = 1; 1650 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun); 1651 } 1652#endif 1653} 1654 1655/* Declare the label NAME global. */ 1656 1657void 1658assemble_global (name) 1659 char *name; 1660{ 1661 ASM_GLOBALIZE_LABEL (asm_out_file, name); 1662} 1663 1664/* Assemble a label named NAME. */ 1665 1666void 1667assemble_label (name) 1668 char *name; 1669{ 1670 ASM_OUTPUT_LABEL (asm_out_file, name); 1671} 1672 1673/* Output to FILE a reference to the assembler name of a C-level name NAME. 1674 If NAME starts with a *, the rest of NAME is output verbatim. 1675 Otherwise NAME is transformed in an implementation-defined way 1676 (usually by the addition of an underscore). 1677 Many macros in the tm file are defined to call this function. */ 1678 1679void 1680assemble_name (file, name) 1681 FILE *file; 1682 char *name; 1683{ 1684 char *real_name; 1685 tree id; 1686 1687 STRIP_NAME_ENCODING (real_name, name); 1688 if (flag_prefix_function_name 1689 && ! bcmp (real_name, CHKR_PREFIX, CHKR_PREFIX_SIZE)) 1690 real_name = real_name + CHKR_PREFIX_SIZE; 1691 1692 id = maybe_get_identifier (real_name); 1693 if (id) 1694 TREE_SYMBOL_REFERENCED (id) = 1; 1695 1696 if (name[0] == '*') 1697 fputs (&name[1], file); 1698 else 1699 ASM_OUTPUT_LABELREF (file, name); 1700} 1701 1702/* Allocate SIZE bytes writable static space with a gensym name 1703 and return an RTX to refer to its address. */ 1704 1705rtx 1706assemble_static_space (size) 1707 int size; 1708{ 1709 char name[12]; 1710 char *namestring; 1711 rtx x; 1712 1713#if 0 1714 if (flag_shared_data) 1715 data_section (); 1716#endif 1717 1718 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno); 1719 ++const_labelno; 1720 1721 namestring = (char *) obstack_alloc (saveable_obstack, 1722 strlen (name) + 2); 1723 strcpy (namestring, name); 1724 1725 x = gen_rtx_SYMBOL_REF (Pmode, namestring); 1726 1727#ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL 1728 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size, 1729 BIGGEST_ALIGNMENT); 1730#else 1731#ifdef ASM_OUTPUT_ALIGNED_LOCAL 1732 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT); 1733#else 1734 { 1735 /* Round size up to multiple of BIGGEST_ALIGNMENT bits 1736 so that each uninitialized object starts on such a boundary. */ 1737 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */ 1738 int rounded ATTRIBUTE_UNUSED 1739 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1) 1740 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) 1741 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); 1742 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); 1743 } 1744#endif 1745#endif 1746 return x; 1747} 1748 1749/* Assemble the static constant template for function entry trampolines. 1750 This is done at most once per compilation. 1751 Returns an RTX for the address of the template. */ 1752 1753#ifdef TRAMPOLINE_TEMPLATE 1754rtx 1755assemble_trampoline_template () 1756{ 1757 char label[256]; 1758 char *name; 1759 int align; 1760 1761 /* By default, put trampoline templates in read-only data section. */ 1762 1763#ifdef TRAMPOLINE_SECTION 1764 TRAMPOLINE_SECTION (); 1765#else 1766 readonly_data_section (); 1767#endif 1768 1769 /* Write the assembler code to define one. */ 1770 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT); 1771 if (align > 0) 1772 ASM_OUTPUT_ALIGN (asm_out_file, align); 1773 1774 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LTRAMP", 0); 1775 TRAMPOLINE_TEMPLATE (asm_out_file); 1776 1777 /* Record the rtl to refer to it. */ 1778 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0); 1779 name 1780 = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label)); 1781 return gen_rtx_SYMBOL_REF (Pmode, name); 1782} 1783#endif 1784 1785/* Assemble the integer constant X into an object of SIZE bytes. 1786 X must be either a CONST_INT or CONST_DOUBLE. 1787 1788 Return 1 if we were able to output the constant, otherwise 0. If FORCE is 1789 non-zero, abort if we can't output the constant. */ 1790 1791int 1792assemble_integer (x, size, force) 1793 rtx x; 1794 int size; 1795 int force; 1796{ 1797 /* First try to use the standard 1, 2, 4, 8, and 16 byte 1798 ASM_OUTPUT... macros. */ 1799 1800 switch (size) 1801 { 1802#ifdef ASM_OUTPUT_CHAR 1803 case 1: 1804 ASM_OUTPUT_CHAR (asm_out_file, x); 1805 return 1; 1806#endif 1807 1808#ifdef ASM_OUTPUT_SHORT 1809 case 2: 1810 ASM_OUTPUT_SHORT (asm_out_file, x); 1811 return 1; 1812#endif 1813 1814#ifdef ASM_OUTPUT_INT 1815 case 4: 1816 ASM_OUTPUT_INT (asm_out_file, x); 1817 return 1; 1818#endif 1819 1820#ifdef ASM_OUTPUT_DOUBLE_INT 1821 case 8: 1822 ASM_OUTPUT_DOUBLE_INT (asm_out_file, x); 1823 return 1; 1824#endif 1825 1826#ifdef ASM_OUTPUT_QUADRUPLE_INT 1827 case 16: 1828 ASM_OUTPUT_QUADRUPLE_INT (asm_out_file, x); 1829 return 1; 1830#endif 1831 } 1832 1833 /* If we couldn't do it that way, there are two other possibilities: First, 1834 if the machine can output an explicit byte and this is a 1 byte constant, 1835 we can use ASM_OUTPUT_BYTE. */ 1836 1837#ifdef ASM_OUTPUT_BYTE 1838 if (size == 1 && GET_CODE (x) == CONST_INT) 1839 { 1840 ASM_OUTPUT_BYTE (asm_out_file, INTVAL (x)); 1841 return 1; 1842 } 1843#endif 1844 1845 /* Finally, if SIZE is larger than a single word, try to output the constant 1846 one word at a time. */ 1847 1848 if (size > UNITS_PER_WORD) 1849 { 1850 int i; 1851 enum machine_mode mode 1852 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0); 1853 rtx word; 1854 1855 for (i = 0; i < size / UNITS_PER_WORD; i++) 1856 { 1857 word = operand_subword (x, i, 0, mode); 1858 1859 if (word == 0) 1860 break; 1861 1862 if (! assemble_integer (word, UNITS_PER_WORD, 0)) 1863 break; 1864 } 1865 1866 if (i == size / UNITS_PER_WORD) 1867 return 1; 1868 /* If we output at least one word and then could not finish, 1869 there is no valid way to continue. */ 1870 if (i > 0) 1871 abort (); 1872 } 1873 1874 if (force) 1875 abort (); 1876 1877 return 0; 1878} 1879 1880/* Assemble the floating-point constant D into an object of size MODE. */ 1881 1882void 1883assemble_real (d, mode) 1884 REAL_VALUE_TYPE d; 1885 enum machine_mode mode; 1886{ 1887 jmp_buf output_constant_handler; 1888 1889 if (setjmp (output_constant_handler)) 1890 { 1891 error ("floating point trap outputting a constant"); 1892#ifdef REAL_IS_NOT_DOUBLE 1893 bzero ((char *) &d, sizeof d); 1894 d = dconst0; 1895#else 1896 d = 0; 1897#endif 1898 } 1899 1900 set_float_handler (output_constant_handler); 1901 1902 switch (mode) 1903 { 1904#ifdef ASM_OUTPUT_BYTE_FLOAT 1905 case QFmode: 1906 ASM_OUTPUT_BYTE_FLOAT (asm_out_file, d); 1907 break; 1908#endif 1909#ifdef ASM_OUTPUT_SHORT_FLOAT 1910 case HFmode: 1911 ASM_OUTPUT_SHORT_FLOAT (asm_out_file, d); 1912 break; 1913#endif 1914#ifdef ASM_OUTPUT_THREE_QUARTER_FLOAT 1915 case TQFmode: 1916 ASM_OUTPUT_THREE_QUARTER_FLOAT (asm_out_file, d); 1917 break; 1918#endif 1919#ifdef ASM_OUTPUT_FLOAT 1920 case SFmode: 1921 ASM_OUTPUT_FLOAT (asm_out_file, d); 1922 break; 1923#endif 1924 1925#ifdef ASM_OUTPUT_DOUBLE 1926 case DFmode: 1927 ASM_OUTPUT_DOUBLE (asm_out_file, d); 1928 break; 1929#endif 1930 1931#ifdef ASM_OUTPUT_LONG_DOUBLE 1932 case XFmode: 1933 case TFmode: 1934 ASM_OUTPUT_LONG_DOUBLE (asm_out_file, d); 1935 break; 1936#endif 1937 1938 default: 1939 abort (); 1940 } 1941 1942 set_float_handler (NULL_PTR); 1943} 1944 1945/* Here we combine duplicate floating constants to make 1946 CONST_DOUBLE rtx's, and force those out to memory when necessary. */ 1947 1948/* Chain of all CONST_DOUBLE rtx's constructed for the current function. 1949 They are chained through the CONST_DOUBLE_CHAIN. 1950 A CONST_DOUBLE rtx has CONST_DOUBLE_MEM != cc0_rtx iff it is on this chain. 1951 In that case, CONST_DOUBLE_MEM is either a MEM, 1952 or const0_rtx if no MEM has been made for this CONST_DOUBLE yet. 1953 1954 (CONST_DOUBLE_MEM is used only for top-level functions. 1955 See force_const_mem for explanation.) */ 1956 1957static rtx const_double_chain; 1958 1959/* Return a CONST_DOUBLE or CONST_INT for a value specified as a pair of ints. 1960 For an integer, I0 is the low-order word and I1 is the high-order word. 1961 For a real number, I0 is the word with the low address 1962 and I1 is the word with the high address. */ 1963 1964rtx 1965immed_double_const (i0, i1, mode) 1966 HOST_WIDE_INT i0, i1; 1967 enum machine_mode mode; 1968{ 1969 register rtx r; 1970 1971 if (GET_MODE_CLASS (mode) == MODE_INT 1972 || GET_MODE_CLASS (mode) == MODE_PARTIAL_INT) 1973 { 1974 /* We clear out all bits that don't belong in MODE, unless they and our 1975 sign bit are all one. So we get either a reasonable negative value 1976 or a reasonable unsigned value for this mode. */ 1977 int width = GET_MODE_BITSIZE (mode); 1978 if (width < HOST_BITS_PER_WIDE_INT 1979 && ((i0 & ((HOST_WIDE_INT) (-1) << (width - 1))) 1980 != ((HOST_WIDE_INT) (-1) << (width - 1)))) 1981 i0 &= ((HOST_WIDE_INT) 1 << width) - 1, i1 = 0; 1982 else if (width == HOST_BITS_PER_WIDE_INT 1983 && ! (i1 == ~0 && i0 < 0)) 1984 i1 = 0; 1985 else if (width > 2 * HOST_BITS_PER_WIDE_INT) 1986 /* We cannot represent this value as a constant. */ 1987 abort (); 1988 1989 /* If this would be an entire word for the target, but is not for 1990 the host, then sign-extend on the host so that the number will look 1991 the same way on the host that it would on the target. 1992 1993 For example, when building a 64 bit alpha hosted 32 bit sparc 1994 targeted compiler, then we want the 32 bit unsigned value -1 to be 1995 represented as a 64 bit value -1, and not as 0x00000000ffffffff. 1996 The later confuses the sparc backend. */ 1997 1998 if (BITS_PER_WORD < HOST_BITS_PER_WIDE_INT && BITS_PER_WORD == width 1999 && (i0 & ((HOST_WIDE_INT) 1 << (width - 1)))) 2000 i0 |= ((HOST_WIDE_INT) (-1) << width); 2001 2002 /* If MODE fits within HOST_BITS_PER_WIDE_INT, always use a CONST_INT. 2003 2004 ??? Strictly speaking, this is wrong if we create a CONST_INT 2005 for a large unsigned constant with the size of MODE being 2006 HOST_BITS_PER_WIDE_INT and later try to interpret that constant in a 2007 wider mode. In that case we will mis-interpret it as a negative 2008 number. 2009 2010 Unfortunately, the only alternative is to make a CONST_DOUBLE 2011 for any constant in any mode if it is an unsigned constant larger 2012 than the maximum signed integer in an int on the host. However, 2013 doing this will break everyone that always expects to see a CONST_INT 2014 for SImode and smaller. 2015 2016 We have always been making CONST_INTs in this case, so nothing new 2017 is being broken. */ 2018 2019 if (width <= HOST_BITS_PER_WIDE_INT) 2020 i1 = (i0 < 0) ? ~(HOST_WIDE_INT) 0 : 0; 2021 2022 /* If this integer fits in one word, return a CONST_INT. */ 2023 if ((i1 == 0 && i0 >= 0) 2024 || (i1 == ~0 && i0 < 0)) 2025 return GEN_INT (i0); 2026 2027 /* We use VOIDmode for integers. */ 2028 mode = VOIDmode; 2029 } 2030 2031 /* Search the chain for an existing CONST_DOUBLE with the right value. 2032 If one is found, return it. */ 2033 2034 for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r)) 2035 if (CONST_DOUBLE_LOW (r) == i0 && CONST_DOUBLE_HIGH (r) == i1 2036 && GET_MODE (r) == mode) 2037 return r; 2038 2039 /* No; make a new one and add it to the chain. 2040 2041 We may be called by an optimizer which may be discarding any memory 2042 allocated during its processing (such as combine and loop). However, 2043 we will be leaving this constant on the chain, so we cannot tolerate 2044 freed memory. So switch to saveable_obstack for this allocation 2045 and then switch back if we were in current_obstack. */ 2046 2047 push_obstacks_nochange (); 2048 rtl_in_saveable_obstack (); 2049 r = gen_rtx_CONST_DOUBLE (mode, NULL_RTX, i0, i1); 2050 pop_obstacks (); 2051 2052 /* Don't touch const_double_chain in nested function; see force_const_mem. 2053 Also, don't touch it if not inside any function. */ 2054 if (outer_function_chain == 0 && current_function_decl != 0) 2055 { 2056 CONST_DOUBLE_CHAIN (r) = const_double_chain; 2057 const_double_chain = r; 2058 } 2059 2060 /* Store const0_rtx in mem-slot since this CONST_DOUBLE is on the chain. 2061 Actual use of mem-slot is only through force_const_mem. */ 2062 2063 CONST_DOUBLE_MEM (r) = const0_rtx; 2064 2065 return r; 2066} 2067 2068/* Return a CONST_DOUBLE for a specified `double' value 2069 and machine mode. */ 2070 2071rtx 2072immed_real_const_1 (d, mode) 2073 REAL_VALUE_TYPE d; 2074 enum machine_mode mode; 2075{ 2076 union real_extract u; 2077 register rtx r; 2078 2079 /* Get the desired `double' value as a sequence of ints 2080 since that is how they are stored in a CONST_DOUBLE. */ 2081 2082 u.d = d; 2083 2084 /* Detect special cases. */ 2085 2086 if (REAL_VALUES_IDENTICAL (dconst0, d)) 2087 return CONST0_RTX (mode); 2088 /* Check for NaN first, because some ports (specifically the i386) do not 2089 emit correct ieee-fp code by default, and thus will generate a core 2090 dump here if we pass a NaN to REAL_VALUES_EQUAL and if REAL_VALUES_EQUAL 2091 does a floating point comparison. */ 2092 else if (! REAL_VALUE_ISNAN (d) && REAL_VALUES_EQUAL (dconst1, d)) 2093 return CONST1_RTX (mode); 2094 2095 if (sizeof u == sizeof (HOST_WIDE_INT)) 2096 return immed_double_const (u.i[0], 0, mode); 2097 if (sizeof u == 2 * sizeof (HOST_WIDE_INT)) 2098 return immed_double_const (u.i[0], u.i[1], mode); 2099 2100 /* The rest of this function handles the case where 2101 a float value requires more than 2 ints of space. 2102 It will be deleted as dead code on machines that don't need it. */ 2103 2104 /* Search the chain for an existing CONST_DOUBLE with the right value. 2105 If one is found, return it. */ 2106 2107 for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r)) 2108 if (! bcmp ((char *) &CONST_DOUBLE_LOW (r), (char *) &u, sizeof u) 2109 && GET_MODE (r) == mode) 2110 return r; 2111 2112 /* No; make a new one and add it to the chain. 2113 2114 We may be called by an optimizer which may be discarding any memory 2115 allocated during its processing (such as combine and loop). However, 2116 we will be leaving this constant on the chain, so we cannot tolerate 2117 freed memory. So switch to saveable_obstack for this allocation 2118 and then switch back if we were in current_obstack. */ 2119 2120 push_obstacks_nochange (); 2121 rtl_in_saveable_obstack (); 2122 r = rtx_alloc (CONST_DOUBLE); 2123 PUT_MODE (r, mode); 2124 bcopy ((char *) &u, (char *) &CONST_DOUBLE_LOW (r), sizeof u); 2125 pop_obstacks (); 2126 2127 /* Don't touch const_double_chain in nested function; see force_const_mem. 2128 Also, don't touch it if not inside any function. */ 2129 if (outer_function_chain == 0 && current_function_decl != 0) 2130 { 2131 CONST_DOUBLE_CHAIN (r) = const_double_chain; 2132 const_double_chain = r; 2133 } 2134 2135 /* Store const0_rtx in CONST_DOUBLE_MEM since this CONST_DOUBLE is on the 2136 chain, but has not been allocated memory. Actual use of CONST_DOUBLE_MEM 2137 is only through force_const_mem. */ 2138 2139 CONST_DOUBLE_MEM (r) = const0_rtx; 2140 2141 return r; 2142} 2143 2144/* Return a CONST_DOUBLE rtx for a value specified by EXP, 2145 which must be a REAL_CST tree node. */ 2146 2147rtx 2148immed_real_const (exp) 2149 tree exp; 2150{ 2151 return immed_real_const_1 (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp))); 2152} 2153 2154/* At the end of a function, forget the memory-constants 2155 previously made for CONST_DOUBLEs. Mark them as not on real_constant_chain. 2156 Also clear out real_constant_chain and clear out all the chain-pointers. */ 2157 2158void 2159clear_const_double_mem () 2160{ 2161 register rtx r, next; 2162 2163 /* Don't touch CONST_DOUBLE_MEM for nested functions. 2164 See force_const_mem for explanation. */ 2165 if (outer_function_chain != 0) 2166 return; 2167 2168 for (r = const_double_chain; r; r = next) 2169 { 2170 next = CONST_DOUBLE_CHAIN (r); 2171 CONST_DOUBLE_CHAIN (r) = 0; 2172 CONST_DOUBLE_MEM (r) = cc0_rtx; 2173 } 2174 const_double_chain = 0; 2175} 2176 2177/* Given an expression EXP with a constant value, 2178 reduce it to the sum of an assembler symbol and an integer. 2179 Store them both in the structure *VALUE. 2180 Abort if EXP does not reduce. */ 2181 2182struct addr_const 2183{ 2184 rtx base; 2185 HOST_WIDE_INT offset; 2186}; 2187 2188static void 2189decode_addr_const (exp, value) 2190 tree exp; 2191 struct addr_const *value; 2192{ 2193 register tree target = TREE_OPERAND (exp, 0); 2194 register int offset = 0; 2195 register rtx x; 2196 2197 while (1) 2198 { 2199 if (TREE_CODE (target) == COMPONENT_REF 2200 && (TREE_CODE (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1))) 2201 == INTEGER_CST)) 2202 { 2203 offset += TREE_INT_CST_LOW (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1))) / BITS_PER_UNIT; 2204 target = TREE_OPERAND (target, 0); 2205 } 2206 else if (TREE_CODE (target) == ARRAY_REF) 2207 { 2208 if (TREE_CODE (TREE_OPERAND (target, 1)) != INTEGER_CST 2209 || TREE_CODE (TYPE_SIZE (TREE_TYPE (target))) != INTEGER_CST) 2210 abort (); 2211 offset += ((TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (target))) 2212 * TREE_INT_CST_LOW (TREE_OPERAND (target, 1))) 2213 / BITS_PER_UNIT); 2214 target = TREE_OPERAND (target, 0); 2215 } 2216 else 2217 break; 2218 } 2219 2220 switch (TREE_CODE (target)) 2221 { 2222 case VAR_DECL: 2223 case FUNCTION_DECL: 2224 x = DECL_RTL (target); 2225 break; 2226 2227 case LABEL_DECL: 2228 x = gen_rtx_MEM (FUNCTION_MODE, 2229 gen_rtx_LABEL_REF (VOIDmode, 2230 label_rtx (TREE_OPERAND (exp, 0)))); 2231 break; 2232 2233 case REAL_CST: 2234 case STRING_CST: 2235 case COMPLEX_CST: 2236 case CONSTRUCTOR: 2237 case INTEGER_CST: 2238 x = TREE_CST_RTL (target); 2239 break; 2240 2241 default: 2242 abort (); 2243 } 2244 2245 if (GET_CODE (x) != MEM) 2246 abort (); 2247 x = XEXP (x, 0); 2248 2249 value->base = x; 2250 value->offset = offset; 2251} 2252 2253/* Uniquize all constants that appear in memory. 2254 Each constant in memory thus far output is recorded 2255 in `const_hash_table' with a `struct constant_descriptor' 2256 that contains a polish representation of the value of 2257 the constant. 2258 2259 We cannot store the trees in the hash table 2260 because the trees may be temporary. */ 2261 2262struct constant_descriptor 2263{ 2264 struct constant_descriptor *next; 2265 char *label; 2266 char contents[1]; 2267}; 2268 2269#define HASHBITS 30 2270#define MAX_HASH_TABLE 1009 2271static struct constant_descriptor *const_hash_table[MAX_HASH_TABLE]; 2272 2273/* Compute a hash code for a constant expression. */ 2274 2275static int 2276const_hash (exp) 2277 tree exp; 2278{ 2279 register char *p; 2280 register int len, hi, i; 2281 register enum tree_code code = TREE_CODE (exp); 2282 2283 /* Either set P and LEN to the address and len of something to hash and 2284 exit the switch or return a value. */ 2285 2286 switch (code) 2287 { 2288 case INTEGER_CST: 2289 p = (char *) &TREE_INT_CST_LOW (exp); 2290 len = 2 * sizeof TREE_INT_CST_LOW (exp); 2291 break; 2292 2293 case REAL_CST: 2294 p = (char *) &TREE_REAL_CST (exp); 2295 len = sizeof TREE_REAL_CST (exp); 2296 break; 2297 2298 case STRING_CST: 2299 p = TREE_STRING_POINTER (exp); 2300 len = TREE_STRING_LENGTH (exp); 2301 break; 2302 2303 case COMPLEX_CST: 2304 return (const_hash (TREE_REALPART (exp)) * 5 2305 + const_hash (TREE_IMAGPART (exp))); 2306 2307 case CONSTRUCTOR: 2308 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2309 { 2310 len = int_size_in_bytes (TREE_TYPE (exp)); 2311 p = (char *) alloca (len); 2312 get_set_constructor_bytes (exp, (unsigned char *) p, len); 2313 break; 2314 } 2315 else 2316 { 2317 register tree link; 2318 2319 /* For record type, include the type in the hashing. 2320 We do not do so for array types 2321 because (1) the sizes of the elements are sufficient 2322 and (2) distinct array types can have the same constructor. 2323 Instead, we include the array size because the constructor could 2324 be shorter. */ 2325 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) 2326 hi = ((unsigned long) TREE_TYPE (exp) & ((1 << HASHBITS) - 1)) 2327 % MAX_HASH_TABLE; 2328 else 2329 hi = ((5 + int_size_in_bytes (TREE_TYPE (exp))) 2330 & ((1 << HASHBITS) - 1)) % MAX_HASH_TABLE; 2331 2332 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2333 if (TREE_VALUE (link)) 2334 hi 2335 = (hi * 603 + const_hash (TREE_VALUE (link))) % MAX_HASH_TABLE; 2336 2337 return hi; 2338 } 2339 2340 case ADDR_EXPR: 2341 { 2342 struct addr_const value; 2343 2344 decode_addr_const (exp, &value); 2345 if (GET_CODE (value.base) == SYMBOL_REF) 2346 { 2347 /* Don't hash the address of the SYMBOL_REF; 2348 only use the offset and the symbol name. */ 2349 hi = value.offset; 2350 p = XSTR (value.base, 0); 2351 for (i = 0; p[i] != 0; i++) 2352 hi = ((hi * 613) + (unsigned) (p[i])); 2353 } 2354 else if (GET_CODE (value.base) == LABEL_REF) 2355 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13; 2356 2357 hi &= (1 << HASHBITS) - 1; 2358 hi %= MAX_HASH_TABLE; 2359 } 2360 return hi; 2361 2362 case PLUS_EXPR: 2363 case MINUS_EXPR: 2364 return (const_hash (TREE_OPERAND (exp, 0)) * 9 2365 + const_hash (TREE_OPERAND (exp, 1))); 2366 2367 case NOP_EXPR: 2368 case CONVERT_EXPR: 2369 case NON_LVALUE_EXPR: 2370 return const_hash (TREE_OPERAND (exp, 0)) * 7 + 2; 2371 2372 default: 2373 abort (); 2374 } 2375 2376 /* Compute hashing function */ 2377 hi = len; 2378 for (i = 0; i < len; i++) 2379 hi = ((hi * 613) + (unsigned) (p[i])); 2380 2381 hi &= (1 << HASHBITS) - 1; 2382 hi %= MAX_HASH_TABLE; 2383 return hi; 2384} 2385 2386/* Compare a constant expression EXP with a constant-descriptor DESC. 2387 Return 1 if DESC describes a constant with the same value as EXP. */ 2388 2389static int 2390compare_constant (exp, desc) 2391 tree exp; 2392 struct constant_descriptor *desc; 2393{ 2394 return 0 != compare_constant_1 (exp, desc->contents); 2395} 2396 2397/* Compare constant expression EXP with a substring P of a constant descriptor. 2398 If they match, return a pointer to the end of the substring matched. 2399 If they do not match, return 0. 2400 2401 Since descriptors are written in polish prefix notation, 2402 this function can be used recursively to test one operand of EXP 2403 against a subdescriptor, and if it succeeds it returns the 2404 address of the subdescriptor for the next operand. */ 2405 2406static char * 2407compare_constant_1 (exp, p) 2408 tree exp; 2409 char *p; 2410{ 2411 register char *strp; 2412 register int len; 2413 register enum tree_code code = TREE_CODE (exp); 2414 2415 if (code != (enum tree_code) *p++) 2416 return 0; 2417 2418 /* Either set STRP, P and LEN to pointers and length to compare and exit the 2419 switch, or return the result of the comparison. */ 2420 2421 switch (code) 2422 { 2423 case INTEGER_CST: 2424 /* Integer constants are the same only if the same width of type. */ 2425 if (*p++ != TYPE_PRECISION (TREE_TYPE (exp))) 2426 return 0; 2427 2428 strp = (char *) &TREE_INT_CST_LOW (exp); 2429 len = 2 * sizeof TREE_INT_CST_LOW (exp); 2430 break; 2431 2432 case REAL_CST: 2433 /* Real constants are the same only if the same width of type. */ 2434 if (*p++ != TYPE_PRECISION (TREE_TYPE (exp))) 2435 return 0; 2436 2437 strp = (char *) &TREE_REAL_CST (exp); 2438 len = sizeof TREE_REAL_CST (exp); 2439 break; 2440 2441 case STRING_CST: 2442 if (flag_writable_strings) 2443 return 0; 2444 2445 if (*p++ != TYPE_MODE (TREE_TYPE (exp))) 2446 return 0; 2447 2448 strp = TREE_STRING_POINTER (exp); 2449 len = TREE_STRING_LENGTH (exp); 2450 if (bcmp ((char *) &TREE_STRING_LENGTH (exp), p, 2451 sizeof TREE_STRING_LENGTH (exp))) 2452 return 0; 2453 2454 p += sizeof TREE_STRING_LENGTH (exp); 2455 break; 2456 2457 case COMPLEX_CST: 2458 p = compare_constant_1 (TREE_REALPART (exp), p); 2459 if (p == 0) 2460 return 0; 2461 2462 return compare_constant_1 (TREE_IMAGPART (exp), p); 2463 2464 case CONSTRUCTOR: 2465 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2466 { 2467 int xlen = len = int_size_in_bytes (TREE_TYPE (exp)); 2468 2469 strp = (char *) alloca (len); 2470 get_set_constructor_bytes (exp, (unsigned char *) strp, len); 2471 if (bcmp ((char *) &xlen, p, sizeof xlen)) 2472 return 0; 2473 2474 p += sizeof xlen; 2475 break; 2476 } 2477 else 2478 { 2479 register tree link; 2480 int length = list_length (CONSTRUCTOR_ELTS (exp)); 2481 tree type; 2482 int have_purpose = 0; 2483 2484 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2485 if (TREE_PURPOSE (link)) 2486 have_purpose = 1; 2487 2488 if (bcmp ((char *) &length, p, sizeof length)) 2489 return 0; 2490 2491 p += sizeof length; 2492 2493 /* For record constructors, insist that the types match. 2494 For arrays, just verify both constructors are for arrays. 2495 Then insist that either both or none have any TREE_PURPOSE 2496 values. */ 2497 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) 2498 type = TREE_TYPE (exp); 2499 else 2500 type = 0; 2501 2502 if (bcmp ((char *) &type, p, sizeof type)) 2503 return 0; 2504 2505 p += sizeof type; 2506 2507 if (bcmp ((char *) &have_purpose, p, sizeof have_purpose)) 2508 return 0; 2509 2510 p += sizeof have_purpose; 2511 2512 /* For arrays, insist that the size in bytes match. */ 2513 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) 2514 { 2515 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (exp)); 2516 2517 if (bcmp ((char *) &size, p, sizeof size)) 2518 return 0; 2519 2520 p += sizeof size; 2521 } 2522 2523 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2524 { 2525 if (TREE_VALUE (link)) 2526 { 2527 if ((p = compare_constant_1 (TREE_VALUE (link), p)) == 0) 2528 return 0; 2529 } 2530 else 2531 { 2532 tree zero = 0; 2533 2534 if (bcmp ((char *) &zero, p, sizeof zero)) 2535 return 0; 2536 2537 p += sizeof zero; 2538 } 2539 2540 if (TREE_PURPOSE (link) 2541 && TREE_CODE (TREE_PURPOSE (link)) == FIELD_DECL) 2542 { 2543 if (bcmp ((char *) &TREE_PURPOSE (link), p, 2544 sizeof TREE_PURPOSE (link))) 2545 return 0; 2546 2547 p += sizeof TREE_PURPOSE (link); 2548 } 2549 else if (TREE_PURPOSE (link)) 2550 { 2551 if ((p = compare_constant_1 (TREE_PURPOSE (link), p)) == 0) 2552 return 0; 2553 } 2554 else if (have_purpose) 2555 { 2556 int zero = 0; 2557 2558 if (bcmp ((char *) &zero, p, sizeof zero)) 2559 return 0; 2560 2561 p += sizeof zero; 2562 } 2563 } 2564 2565 return p; 2566 } 2567 2568 case ADDR_EXPR: 2569 { 2570 struct addr_const value; 2571 2572 decode_addr_const (exp, &value); 2573 strp = (char *) &value.offset; 2574 len = sizeof value.offset; 2575 /* Compare the offset. */ 2576 while (--len >= 0) 2577 if (*p++ != *strp++) 2578 return 0; 2579 2580 /* Compare symbol name. */ 2581 strp = XSTR (value.base, 0); 2582 len = strlen (strp) + 1; 2583 } 2584 break; 2585 2586 case PLUS_EXPR: 2587 case MINUS_EXPR: 2588 case RANGE_EXPR: 2589 p = compare_constant_1 (TREE_OPERAND (exp, 0), p); 2590 if (p == 0) 2591 return 0; 2592 2593 return compare_constant_1 (TREE_OPERAND (exp, 1), p); 2594 2595 case NOP_EXPR: 2596 case CONVERT_EXPR: 2597 case NON_LVALUE_EXPR: 2598 return compare_constant_1 (TREE_OPERAND (exp, 0), p); 2599 2600 default: 2601 abort (); 2602 } 2603 2604 /* Compare constant contents. */ 2605 while (--len >= 0) 2606 if (*p++ != *strp++) 2607 return 0; 2608 2609 return p; 2610} 2611 2612/* Construct a constant descriptor for the expression EXP. 2613 It is up to the caller to enter the descriptor in the hash table. */ 2614 2615static struct constant_descriptor * 2616record_constant (exp) 2617 tree exp; 2618{ 2619 struct constant_descriptor *next = 0; 2620 char *label = 0; 2621 2622 /* Make a struct constant_descriptor. The first two pointers will 2623 be filled in later. Here we just leave space for them. */ 2624 2625 obstack_grow (&permanent_obstack, (char *) &next, sizeof next); 2626 obstack_grow (&permanent_obstack, (char *) &label, sizeof label); 2627 record_constant_1 (exp); 2628 return (struct constant_descriptor *) obstack_finish (&permanent_obstack); 2629} 2630 2631/* Add a description of constant expression EXP 2632 to the object growing in `permanent_obstack'. 2633 No need to return its address; the caller will get that 2634 from the obstack when the object is complete. */ 2635 2636static void 2637record_constant_1 (exp) 2638 tree exp; 2639{ 2640 register char *strp; 2641 register int len; 2642 register enum tree_code code = TREE_CODE (exp); 2643 2644 obstack_1grow (&permanent_obstack, (unsigned int) code); 2645 2646 switch (code) 2647 { 2648 case INTEGER_CST: 2649 obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp))); 2650 strp = (char *) &TREE_INT_CST_LOW (exp); 2651 len = 2 * sizeof TREE_INT_CST_LOW (exp); 2652 break; 2653 2654 case REAL_CST: 2655 obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp))); 2656 strp = (char *) &TREE_REAL_CST (exp); 2657 len = sizeof TREE_REAL_CST (exp); 2658 break; 2659 2660 case STRING_CST: 2661 if (flag_writable_strings) 2662 return; 2663 2664 obstack_1grow (&permanent_obstack, TYPE_MODE (TREE_TYPE (exp))); 2665 strp = TREE_STRING_POINTER (exp); 2666 len = TREE_STRING_LENGTH (exp); 2667 obstack_grow (&permanent_obstack, (char *) &TREE_STRING_LENGTH (exp), 2668 sizeof TREE_STRING_LENGTH (exp)); 2669 break; 2670 2671 case COMPLEX_CST: 2672 record_constant_1 (TREE_REALPART (exp)); 2673 record_constant_1 (TREE_IMAGPART (exp)); 2674 return; 2675 2676 case CONSTRUCTOR: 2677 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2678 { 2679 int nbytes = int_size_in_bytes (TREE_TYPE (exp)); 2680 obstack_grow (&permanent_obstack, &nbytes, sizeof (nbytes)); 2681 obstack_blank (&permanent_obstack, nbytes); 2682 get_set_constructor_bytes 2683 (exp, (unsigned char *) permanent_obstack.next_free-nbytes, 2684 nbytes); 2685 return; 2686 } 2687 else 2688 { 2689 register tree link; 2690 int length = list_length (CONSTRUCTOR_ELTS (exp)); 2691 tree type; 2692 int have_purpose = 0; 2693 2694 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2695 if (TREE_PURPOSE (link)) 2696 have_purpose = 1; 2697 2698 obstack_grow (&permanent_obstack, (char *) &length, sizeof length); 2699 2700 /* For record constructors, insist that the types match. 2701 For arrays, just verify both constructors are for arrays. 2702 Then insist that either both or none have any TREE_PURPOSE 2703 values. */ 2704 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) 2705 type = TREE_TYPE (exp); 2706 else 2707 type = 0; 2708 obstack_grow (&permanent_obstack, (char *) &type, sizeof type); 2709 obstack_grow (&permanent_obstack, (char *) &have_purpose, 2710 sizeof have_purpose); 2711 2712 /* For arrays, insist that the size in bytes match. */ 2713 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) 2714 { 2715 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (exp)); 2716 obstack_grow (&permanent_obstack, (char *) &size, sizeof size); 2717 } 2718 2719 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2720 { 2721 if (TREE_VALUE (link)) 2722 record_constant_1 (TREE_VALUE (link)); 2723 else 2724 { 2725 tree zero = 0; 2726 2727 obstack_grow (&permanent_obstack, 2728 (char *) &zero, sizeof zero); 2729 } 2730 2731 if (TREE_PURPOSE (link) 2732 && TREE_CODE (TREE_PURPOSE (link)) == FIELD_DECL) 2733 obstack_grow (&permanent_obstack, 2734 (char *) &TREE_PURPOSE (link), 2735 sizeof TREE_PURPOSE (link)); 2736 else if (TREE_PURPOSE (link)) 2737 record_constant_1 (TREE_PURPOSE (link)); 2738 else if (have_purpose) 2739 { 2740 int zero = 0; 2741 2742 obstack_grow (&permanent_obstack, 2743 (char *) &zero, sizeof zero); 2744 } 2745 } 2746 } 2747 return; 2748 2749 case ADDR_EXPR: 2750 { 2751 struct addr_const value; 2752 2753 decode_addr_const (exp, &value); 2754 /* Record the offset. */ 2755 obstack_grow (&permanent_obstack, 2756 (char *) &value.offset, sizeof value.offset); 2757 /* Record the symbol name. */ 2758 obstack_grow (&permanent_obstack, XSTR (value.base, 0), 2759 strlen (XSTR (value.base, 0)) + 1); 2760 } 2761 return; 2762 2763 case PLUS_EXPR: 2764 case MINUS_EXPR: 2765 case RANGE_EXPR: 2766 record_constant_1 (TREE_OPERAND (exp, 0)); 2767 record_constant_1 (TREE_OPERAND (exp, 1)); 2768 return; 2769 2770 case NOP_EXPR: 2771 case CONVERT_EXPR: 2772 case NON_LVALUE_EXPR: 2773 record_constant_1 (TREE_OPERAND (exp, 0)); 2774 return; 2775 2776 default: 2777 abort (); 2778 } 2779 2780 /* Record constant contents. */ 2781 obstack_grow (&permanent_obstack, strp, len); 2782} 2783 2784/* Record a list of constant expressions that were passed to 2785 output_constant_def but that could not be output right away. */ 2786 2787struct deferred_constant 2788{ 2789 struct deferred_constant *next; 2790 tree exp; 2791 int reloc; 2792 int labelno; 2793}; 2794 2795static struct deferred_constant *deferred_constants; 2796 2797/* Another list of constants which should be output after the 2798 function. */ 2799static struct deferred_constant *after_function_constants; 2800 2801/* Nonzero means defer output of addressed subconstants 2802 (i.e., those for which output_constant_def is called.) */ 2803static int defer_addressed_constants_flag; 2804 2805/* Start deferring output of subconstants. */ 2806 2807void 2808defer_addressed_constants () 2809{ 2810 defer_addressed_constants_flag++; 2811} 2812 2813/* Stop deferring output of subconstants, 2814 and output now all those that have been deferred. */ 2815 2816void 2817output_deferred_addressed_constants () 2818{ 2819 struct deferred_constant *p, *next; 2820 2821 defer_addressed_constants_flag--; 2822 2823 if (defer_addressed_constants_flag > 0) 2824 return; 2825 2826 for (p = deferred_constants; p; p = next) 2827 { 2828 output_constant_def_contents (p->exp, p->reloc, p->labelno); 2829 next = p->next; 2830 free (p); 2831 } 2832 2833 deferred_constants = 0; 2834} 2835 2836/* Output any constants which should appear after a function. */ 2837 2838static void 2839output_after_function_constants () 2840{ 2841 struct deferred_constant *p, *next; 2842 2843 for (p = after_function_constants; p; p = next) 2844 { 2845 output_constant_def_contents (p->exp, p->reloc, p->labelno); 2846 next = p->next; 2847 free (p); 2848 } 2849 2850 after_function_constants = 0; 2851} 2852 2853/* Make a copy of the whole tree structure for a constant. 2854 This handles the same types of nodes that compare_constant 2855 and record_constant handle. */ 2856 2857static tree 2858copy_constant (exp) 2859 tree exp; 2860{ 2861 switch (TREE_CODE (exp)) 2862 { 2863 case ADDR_EXPR: 2864 /* For ADDR_EXPR, we do not want to copy the decl whose address 2865 is requested. We do want to copy constants though. */ 2866 if (TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, 0))) == 'c') 2867 return build1 (TREE_CODE (exp), TREE_TYPE (exp), 2868 copy_constant (TREE_OPERAND (exp, 0))); 2869 else 2870 return copy_node (exp); 2871 2872 case INTEGER_CST: 2873 case REAL_CST: 2874 case STRING_CST: 2875 return copy_node (exp); 2876 2877 case COMPLEX_CST: 2878 return build_complex (TREE_TYPE (exp), 2879 copy_constant (TREE_REALPART (exp)), 2880 copy_constant (TREE_IMAGPART (exp))); 2881 2882 case PLUS_EXPR: 2883 case MINUS_EXPR: 2884 return build (TREE_CODE (exp), TREE_TYPE (exp), 2885 copy_constant (TREE_OPERAND (exp, 0)), 2886 copy_constant (TREE_OPERAND (exp, 1))); 2887 2888 case NOP_EXPR: 2889 case CONVERT_EXPR: 2890 case NON_LVALUE_EXPR: 2891 return build1 (TREE_CODE (exp), TREE_TYPE (exp), 2892 copy_constant (TREE_OPERAND (exp, 0))); 2893 2894 case CONSTRUCTOR: 2895 { 2896 tree copy = copy_node (exp); 2897 tree list = copy_list (CONSTRUCTOR_ELTS (exp)); 2898 tree tail; 2899 2900 CONSTRUCTOR_ELTS (copy) = list; 2901 for (tail = list; tail; tail = TREE_CHAIN (tail)) 2902 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail)); 2903 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2904 for (tail = list; tail; tail = TREE_CHAIN (tail)) 2905 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail)); 2906 2907 return copy; 2908 } 2909 2910 default: 2911 abort (); 2912 } 2913} 2914 2915/* Return an rtx representing a reference to constant data in memory 2916 for the constant expression EXP. 2917 2918 If assembler code for such a constant has already been output, 2919 return an rtx to refer to it. 2920 Otherwise, output such a constant in memory (or defer it for later) 2921 and generate an rtx for it. 2922 2923 The TREE_CST_RTL of EXP is set up to point to that rtx. 2924 The const_hash_table records which constants already have label strings. */ 2925 2926rtx 2927output_constant_def (exp) 2928 tree exp; 2929{ 2930 register int hash; 2931 register struct constant_descriptor *desc; 2932 char label[256]; 2933 char *found = 0; 2934 int reloc; 2935 register rtx def; 2936 2937 if (TREE_CST_RTL (exp)) 2938 return TREE_CST_RTL (exp); 2939 2940 /* Make sure any other constants whose addresses appear in EXP 2941 are assigned label numbers. */ 2942 2943 reloc = output_addressed_constants (exp); 2944 2945 /* Compute hash code of EXP. Search the descriptors for that hash code 2946 to see if any of them describes EXP. If yes, the descriptor records 2947 the label number already assigned. */ 2948 2949 hash = const_hash (exp) % MAX_HASH_TABLE; 2950 2951 for (desc = const_hash_table[hash]; desc; desc = desc->next) 2952 if (compare_constant (exp, desc)) 2953 { 2954 found = desc->label; 2955 break; 2956 } 2957 2958 if (found == 0) 2959 { 2960 /* No constant equal to EXP is known to have been output. 2961 Make a constant descriptor to enter EXP in the hash table. 2962 Assign the label number and record it in the descriptor for 2963 future calls to this function to find. */ 2964 2965 /* Create a string containing the label name, in LABEL. */ 2966 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); 2967 2968 desc = record_constant (exp); 2969 desc->next = const_hash_table[hash]; 2970 desc->label 2971 = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label)); 2972 const_hash_table[hash] = desc; 2973 } 2974 else 2975 { 2976 /* Create a string containing the label name, in LABEL. */ 2977 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); 2978 } 2979 2980 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */ 2981 2982 push_obstacks_nochange (); 2983 if (TREE_PERMANENT (exp)) 2984 end_temporary_allocation (); 2985 2986 def = gen_rtx_SYMBOL_REF (Pmode, desc->label); 2987 2988 TREE_CST_RTL (exp) 2989 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), def); 2990 RTX_UNCHANGING_P (TREE_CST_RTL (exp)) = 1; 2991 if (AGGREGATE_TYPE_P (TREE_TYPE (exp))) 2992 MEM_SET_IN_STRUCT_P (TREE_CST_RTL (exp), 1); 2993 2994 pop_obstacks (); 2995 2996 /* Optionally set flags or add text to the name to record information 2997 such as that it is a function name. If the name is changed, the macro 2998 ASM_OUTPUT_LABELREF will have to know how to strip this information. */ 2999#ifdef ENCODE_SECTION_INFO 3000 ENCODE_SECTION_INFO (exp); 3001#endif 3002 3003 /* If this is the first time we've seen this particular constant, 3004 output it (or defer its output for later). */ 3005 if (found == 0) 3006 { 3007 int after_function = 0; 3008 3009#ifdef CONSTANT_AFTER_FUNCTION_P 3010 if (current_function_decl != 0 3011 && CONSTANT_AFTER_FUNCTION_P (exp)) 3012 after_function = 1; 3013#endif 3014 3015 if (defer_addressed_constants_flag || after_function) 3016 { 3017 struct deferred_constant *p; 3018 p = (struct deferred_constant *) xmalloc (sizeof (struct deferred_constant)); 3019 3020 push_obstacks_nochange (); 3021 suspend_momentary (); 3022 p->exp = copy_constant (exp); 3023 pop_obstacks (); 3024 p->reloc = reloc; 3025 p->labelno = const_labelno++; 3026 if (after_function) 3027 { 3028 p->next = after_function_constants; 3029 after_function_constants = p; 3030 } 3031 else 3032 { 3033 p->next = deferred_constants; 3034 deferred_constants = p; 3035 } 3036 } 3037 else 3038 { 3039 /* Do no output if -fsyntax-only. */ 3040 if (! flag_syntax_only) 3041 output_constant_def_contents (exp, reloc, const_labelno); 3042 ++const_labelno; 3043 } 3044 } 3045 3046 return TREE_CST_RTL (exp); 3047} 3048 3049/* Now output assembler code to define the label for EXP, 3050 and follow it with the data of EXP. */ 3051 3052static void 3053output_constant_def_contents (exp, reloc, labelno) 3054 tree exp; 3055 int reloc; 3056 int labelno; 3057{ 3058 int align; 3059 3060 if (IN_NAMED_SECTION (exp)) 3061 named_section (exp, NULL, reloc); 3062 else 3063 { 3064 /* First switch to text section, except for writable strings. */ 3065#ifdef SELECT_SECTION 3066 SELECT_SECTION (exp, reloc); 3067#else 3068 if (((TREE_CODE (exp) == STRING_CST) && flag_writable_strings) 3069 || (flag_pic && reloc)) 3070 data_section (); 3071 else 3072 readonly_data_section (); 3073#endif 3074 } 3075 3076 /* Align the location counter as required by EXP's data type. */ 3077 align = TYPE_ALIGN (TREE_TYPE (exp)); 3078#ifdef CONSTANT_ALIGNMENT 3079 align = CONSTANT_ALIGNMENT (exp, align); 3080#endif 3081 3082 if (align > BITS_PER_UNIT) 3083 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 3084 3085 /* Output the label itself. */ 3086 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", labelno); 3087 3088 /* Output the value of EXP. */ 3089 output_constant (exp, 3090 (TREE_CODE (exp) == STRING_CST 3091 ? TREE_STRING_LENGTH (exp) 3092 : int_size_in_bytes (TREE_TYPE (exp)))); 3093 3094} 3095 3096/* Similar hash facility for making memory-constants 3097 from constant rtl-expressions. It is used on RISC machines 3098 where immediate integer arguments and constant addresses are restricted 3099 so that such constants must be stored in memory. 3100 3101 This pool of constants is reinitialized for each function 3102 so each function gets its own constants-pool that comes right before it. 3103 3104 All structures allocated here are discarded when functions are saved for 3105 inlining, so they do not need to be allocated permanently. */ 3106 3107#define MAX_RTX_HASH_TABLE 61 3108static struct constant_descriptor **const_rtx_hash_table; 3109 3110/* Structure to represent sufficient information about a constant so that 3111 it can be output when the constant pool is output, so that function 3112 integration can be done, and to simplify handling on machines that reference 3113 constant pool as base+displacement. */ 3114 3115struct pool_constant 3116{ 3117 struct constant_descriptor *desc; 3118 struct pool_constant *next; 3119 enum machine_mode mode; 3120 rtx constant; 3121 int labelno; 3122 int align; 3123 int offset; 3124 int mark; 3125}; 3126 3127/* Pointers to first and last constant in pool. */ 3128 3129static struct pool_constant *first_pool, *last_pool; 3130 3131/* Current offset in constant pool (does not include any machine-specific 3132 header. */ 3133 3134static int pool_offset; 3135 3136/* Structure used to maintain hash table mapping symbols used to their 3137 corresponding constants. */ 3138 3139struct pool_sym 3140{ 3141 char *label; 3142 struct pool_constant *pool; 3143 struct pool_sym *next; 3144}; 3145 3146static struct pool_sym **const_rtx_sym_hash_table; 3147 3148/* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true. 3149 The argument is XSTR (... , 0) */ 3150 3151#define SYMHASH(LABEL) \ 3152 ((((unsigned long) (LABEL)) & ((1 << HASHBITS) - 1)) % MAX_RTX_HASH_TABLE) 3153 3154/* Initialize constant pool hashing for next function. */ 3155 3156void 3157init_const_rtx_hash_table () 3158{ 3159 const_rtx_hash_table 3160 = ((struct constant_descriptor **) 3161 oballoc (MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *))); 3162 const_rtx_sym_hash_table 3163 = ((struct pool_sym **) 3164 oballoc (MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *))); 3165 bzero ((char *) const_rtx_hash_table, 3166 MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *)); 3167 bzero ((char *) const_rtx_sym_hash_table, 3168 MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *)); 3169 3170 first_pool = last_pool = 0; 3171 pool_offset = 0; 3172} 3173 3174/* Save and restore status for a nested function. */ 3175 3176void 3177save_varasm_status (p, context) 3178 struct function *p; 3179 tree context; 3180{ 3181 p->const_rtx_hash_table = const_rtx_hash_table; 3182 p->const_rtx_sym_hash_table = const_rtx_sym_hash_table; 3183 p->first_pool = first_pool; 3184 p->last_pool = last_pool; 3185 p->pool_offset = pool_offset; 3186 p->const_double_chain = const_double_chain; 3187 3188 /* If we are pushing to toplevel, we can't reuse const_double_chain. */ 3189 if (context == NULL_TREE) 3190 const_double_chain = 0; 3191} 3192 3193void 3194restore_varasm_status (p) 3195 struct function *p; 3196{ 3197 const_rtx_hash_table = p->const_rtx_hash_table; 3198 const_rtx_sym_hash_table = p->const_rtx_sym_hash_table; 3199 first_pool = p->first_pool; 3200 last_pool = p->last_pool; 3201 pool_offset = p->pool_offset; 3202 const_double_chain = p->const_double_chain; 3203} 3204 3205enum kind { RTX_DOUBLE, RTX_INT }; 3206 3207struct rtx_const 3208{ 3209#ifdef ONLY_INT_FIELDS 3210 unsigned int kind : 16; 3211 unsigned int mode : 16; 3212#else 3213 enum kind kind : 16; 3214 enum machine_mode mode : 16; 3215#endif 3216 union { 3217 union real_extract du; 3218 struct addr_const addr; 3219 struct {HOST_WIDE_INT high, low;} di; 3220 } un; 3221}; 3222 3223/* Express an rtx for a constant integer (perhaps symbolic) 3224 as the sum of a symbol or label plus an explicit integer. 3225 They are stored into VALUE. */ 3226 3227static void 3228decode_rtx_const (mode, x, value) 3229 enum machine_mode mode; 3230 rtx x; 3231 struct rtx_const *value; 3232{ 3233 /* Clear the whole structure, including any gaps. */ 3234 3235 { 3236 int *p = (int *) value; 3237 int *end = (int *) (value + 1); 3238 while (p < end) 3239 *p++ = 0; 3240 } 3241 3242 value->kind = RTX_INT; /* Most usual kind. */ 3243 value->mode = mode; 3244 3245 switch (GET_CODE (x)) 3246 { 3247 case CONST_DOUBLE: 3248 value->kind = RTX_DOUBLE; 3249 if (GET_MODE (x) != VOIDmode) 3250 { 3251 value->mode = GET_MODE (x); 3252 bcopy ((char *) &CONST_DOUBLE_LOW (x), 3253 (char *) &value->un.du, sizeof value->un.du); 3254 } 3255 else 3256 { 3257 value->un.di.low = CONST_DOUBLE_LOW (x); 3258 value->un.di.high = CONST_DOUBLE_HIGH (x); 3259 } 3260 break; 3261 3262 case CONST_INT: 3263 value->un.addr.offset = INTVAL (x); 3264 break; 3265 3266 case SYMBOL_REF: 3267 case LABEL_REF: 3268 case PC: 3269 value->un.addr.base = x; 3270 break; 3271 3272 case CONST: 3273 x = XEXP (x, 0); 3274 if (GET_CODE (x) == PLUS) 3275 { 3276 value->un.addr.base = XEXP (x, 0); 3277 if (GET_CODE (XEXP (x, 1)) != CONST_INT) 3278 abort (); 3279 value->un.addr.offset = INTVAL (XEXP (x, 1)); 3280 } 3281 else if (GET_CODE (x) == MINUS) 3282 { 3283 value->un.addr.base = XEXP (x, 0); 3284 if (GET_CODE (XEXP (x, 1)) != CONST_INT) 3285 abort (); 3286 value->un.addr.offset = - INTVAL (XEXP (x, 1)); 3287 } 3288 else 3289 abort (); 3290 break; 3291 3292 default: 3293 abort (); 3294 } 3295 3296 if (value->kind == RTX_INT && value->un.addr.base != 0) 3297 switch (GET_CODE (value->un.addr.base)) 3298 { 3299 case SYMBOL_REF: 3300 case LABEL_REF: 3301 /* Use the string's address, not the SYMBOL_REF's address, 3302 for the sake of addresses of library routines. 3303 For a LABEL_REF, compare labels. */ 3304 value->un.addr.base = XEXP (value->un.addr.base, 0); 3305 3306 default: 3307 break; 3308 } 3309} 3310 3311/* Given a MINUS expression, simplify it if both sides 3312 include the same symbol. */ 3313 3314rtx 3315simplify_subtraction (x) 3316 rtx x; 3317{ 3318 struct rtx_const val0, val1; 3319 3320 decode_rtx_const (GET_MODE (x), XEXP (x, 0), &val0); 3321 decode_rtx_const (GET_MODE (x), XEXP (x, 1), &val1); 3322 3323 if (val0.un.addr.base == val1.un.addr.base) 3324 return GEN_INT (val0.un.addr.offset - val1.un.addr.offset); 3325 return x; 3326} 3327 3328/* Compute a hash code for a constant RTL expression. */ 3329 3330static int 3331const_hash_rtx (mode, x) 3332 enum machine_mode mode; 3333 rtx x; 3334{ 3335 register int hi; 3336 register size_t i; 3337 3338 struct rtx_const value; 3339 decode_rtx_const (mode, x, &value); 3340 3341 /* Compute hashing function */ 3342 hi = 0; 3343 for (i = 0; i < sizeof value / sizeof (int); i++) 3344 hi += ((int *) &value)[i]; 3345 3346 hi &= (1 << HASHBITS) - 1; 3347 hi %= MAX_RTX_HASH_TABLE; 3348 return hi; 3349} 3350 3351/* Compare a constant rtl object X with a constant-descriptor DESC. 3352 Return 1 if DESC describes a constant with the same value as X. */ 3353 3354static int 3355compare_constant_rtx (mode, x, desc) 3356 enum machine_mode mode; 3357 rtx x; 3358 struct constant_descriptor *desc; 3359{ 3360 register int *p = (int *) desc->contents; 3361 register int *strp; 3362 register int len; 3363 struct rtx_const value; 3364 3365 decode_rtx_const (mode, x, &value); 3366 strp = (int *) &value; 3367 len = sizeof value / sizeof (int); 3368 3369 /* Compare constant contents. */ 3370 while (--len >= 0) 3371 if (*p++ != *strp++) 3372 return 0; 3373 3374 return 1; 3375} 3376 3377/* Construct a constant descriptor for the rtl-expression X. 3378 It is up to the caller to enter the descriptor in the hash table. */ 3379 3380static struct constant_descriptor * 3381record_constant_rtx (mode, x) 3382 enum machine_mode mode; 3383 rtx x; 3384{ 3385 struct constant_descriptor *ptr; 3386 char *label; 3387 struct rtx_const value; 3388 3389 decode_rtx_const (mode, x, &value); 3390 3391 /* Put these things in the saveable obstack so we can ensure it won't 3392 be freed if we are called from combine or some other phase that discards 3393 memory allocated from function_obstack (current_obstack). */ 3394 obstack_grow (saveable_obstack, &ptr, sizeof ptr); 3395 obstack_grow (saveable_obstack, &label, sizeof label); 3396 3397 /* Record constant contents. */ 3398 obstack_grow (saveable_obstack, &value, sizeof value); 3399 3400 return (struct constant_descriptor *) obstack_finish (saveable_obstack); 3401} 3402 3403/* Given a constant rtx X, make (or find) a memory constant for its value 3404 and return a MEM rtx to refer to it in memory. */ 3405 3406rtx 3407force_const_mem (mode, x) 3408 enum machine_mode mode; 3409 rtx x; 3410{ 3411 register int hash; 3412 register struct constant_descriptor *desc; 3413 char label[256]; 3414 char *found = 0; 3415 rtx def; 3416 3417 /* If we want this CONST_DOUBLE in the same mode as it is in memory 3418 (this will always be true for floating CONST_DOUBLEs that have been 3419 placed in memory, but not for VOIDmode (integer) CONST_DOUBLEs), 3420 use the previous copy. Otherwise, make a new one. Note that in 3421 the unlikely event that this same CONST_DOUBLE is used in two different 3422 modes in an alternating fashion, we will allocate a lot of different 3423 memory locations, but this should be extremely rare. */ 3424 3425 /* Don't use CONST_DOUBLE_MEM in a nested function. 3426 Nested functions have their own constant pools, 3427 so they can't share the same values in CONST_DOUBLE_MEM 3428 with the containing function. */ 3429 if (outer_function_chain == 0) 3430 if (GET_CODE (x) == CONST_DOUBLE 3431 && GET_CODE (CONST_DOUBLE_MEM (x)) == MEM 3432 && GET_MODE (CONST_DOUBLE_MEM (x)) == mode) 3433 return CONST_DOUBLE_MEM (x); 3434 3435 /* Compute hash code of X. Search the descriptors for that hash code 3436 to see if any of them describes X. If yes, the descriptor records 3437 the label number already assigned. */ 3438 3439 hash = const_hash_rtx (mode, x); 3440 3441 for (desc = const_rtx_hash_table[hash]; desc; desc = desc->next) 3442 if (compare_constant_rtx (mode, x, desc)) 3443 { 3444 found = desc->label; 3445 break; 3446 } 3447 3448 if (found == 0) 3449 { 3450 register struct pool_constant *pool; 3451 register struct pool_sym *sym; 3452 int align; 3453 3454 /* No constant equal to X is known to have been output. 3455 Make a constant descriptor to enter X in the hash table. 3456 Assign the label number and record it in the descriptor for 3457 future calls to this function to find. */ 3458 3459 desc = record_constant_rtx (mode, x); 3460 desc->next = const_rtx_hash_table[hash]; 3461 const_rtx_hash_table[hash] = desc; 3462 3463 /* Align the location counter as required by EXP's data type. */ 3464 align = (mode == VOIDmode) ? UNITS_PER_WORD : GET_MODE_SIZE (mode); 3465 if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT) 3466 align = BIGGEST_ALIGNMENT / BITS_PER_UNIT; 3467#ifdef CONSTANT_ALIGNMENT 3468 align = CONSTANT_ALIGNMENT (make_tree (type_for_mode (mode, 0), x), 3469 align * BITS_PER_UNIT) / BITS_PER_UNIT; 3470#endif 3471 3472 pool_offset += align - 1; 3473 pool_offset &= ~ (align - 1); 3474 3475 /* If RTL is not being placed into the saveable obstack, make a 3476 copy of X that is in the saveable obstack in case we are 3477 being called from combine or some other phase that discards 3478 memory it allocates. We used to only do this if it is a 3479 CONST; however, reload can allocate a CONST_INT when 3480 eliminating registers. */ 3481 if (rtl_obstack != saveable_obstack 3482 && (GET_CODE (x) == CONST || GET_CODE (x) == CONST_INT)) 3483 { 3484 push_obstacks_nochange (); 3485 rtl_in_saveable_obstack (); 3486 3487 if (GET_CODE (x) == CONST) 3488 x = gen_rtx_CONST (GET_MODE (x), 3489 gen_rtx_PLUS (GET_MODE (x), 3490 XEXP (XEXP (x, 0), 0), 3491 XEXP (XEXP (x, 0), 1))); 3492 else 3493 x = GEN_INT (INTVAL (x)); 3494 3495 pop_obstacks (); 3496 } 3497 3498 /* Allocate a pool constant descriptor, fill it in, and chain it in. */ 3499 3500 pool = (struct pool_constant *) savealloc (sizeof (struct pool_constant)); 3501 pool->desc = desc; 3502 pool->constant = x; 3503 pool->mode = mode; 3504 pool->labelno = const_labelno; 3505 pool->align = align; 3506 pool->offset = pool_offset; 3507 pool->mark = 1; 3508 pool->next = 0; 3509 3510 if (last_pool == 0) 3511 first_pool = pool; 3512 else 3513 last_pool->next = pool; 3514 3515 last_pool = pool; 3516 pool_offset += GET_MODE_SIZE (mode); 3517 3518 /* Create a string containing the label name, in LABEL. */ 3519 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); 3520 3521 ++const_labelno; 3522 3523 desc->label = found 3524 = (char *) obstack_copy0 (saveable_obstack, label, strlen (label)); 3525 3526 /* Add label to symbol hash table. */ 3527 hash = SYMHASH (found); 3528 sym = (struct pool_sym *) savealloc (sizeof (struct pool_sym)); 3529 sym->label = found; 3530 sym->pool = pool; 3531 sym->next = const_rtx_sym_hash_table[hash]; 3532 const_rtx_sym_hash_table[hash] = sym; 3533 } 3534 3535 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */ 3536 3537 def = gen_rtx_MEM (mode, gen_rtx_SYMBOL_REF (Pmode, found)); 3538 3539 RTX_UNCHANGING_P (def) = 1; 3540 /* Mark the symbol_ref as belonging to this constants pool. */ 3541 CONSTANT_POOL_ADDRESS_P (XEXP (def, 0)) = 1; 3542 current_function_uses_const_pool = 1; 3543 3544 if (outer_function_chain == 0) 3545 if (GET_CODE (x) == CONST_DOUBLE) 3546 { 3547 if (CONST_DOUBLE_MEM (x) == cc0_rtx) 3548 { 3549 CONST_DOUBLE_CHAIN (x) = const_double_chain; 3550 const_double_chain = x; 3551 } 3552 CONST_DOUBLE_MEM (x) = def; 3553 } 3554 3555 return def; 3556} 3557 3558/* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to 3559 the corresponding pool_constant structure. */ 3560 3561static struct pool_constant * 3562find_pool_constant (addr) 3563 rtx addr; 3564{ 3565 struct pool_sym *sym; 3566 char *label = XSTR (addr, 0); 3567 3568 for (sym = const_rtx_sym_hash_table[SYMHASH (label)]; sym; sym = sym->next) 3569 if (sym->label == label) 3570 return sym->pool; 3571 3572 abort (); 3573} 3574 3575/* Given a constant pool SYMBOL_REF, return the corresponding constant. */ 3576 3577rtx 3578get_pool_constant (addr) 3579 rtx addr; 3580{ 3581 return (find_pool_constant (addr))->constant; 3582} 3583 3584/* Similar, return the mode. */ 3585 3586enum machine_mode 3587get_pool_mode (addr) 3588 rtx addr; 3589{ 3590 return (find_pool_constant (addr))->mode; 3591} 3592 3593/* Similar, return the offset in the constant pool. */ 3594 3595int 3596get_pool_offset (addr) 3597 rtx addr; 3598{ 3599 return (find_pool_constant (addr))->offset; 3600} 3601 3602/* Return the size of the constant pool. */ 3603 3604int 3605get_pool_size () 3606{ 3607 return pool_offset; 3608} 3609 3610/* Write all the constants in the constant pool. */ 3611 3612void 3613output_constant_pool (fnname, fndecl) 3614 char *fnname ATTRIBUTE_UNUSED; 3615 tree fndecl ATTRIBUTE_UNUSED; 3616{ 3617 struct pool_constant *pool; 3618 rtx x; 3619 union real_extract u; 3620 3621 /* It is possible for gcc to call force_const_mem and then to later 3622 discard the instructions which refer to the constant. In such a 3623 case we do not need to output the constant. */ 3624 mark_constant_pool (); 3625 3626#ifdef ASM_OUTPUT_POOL_PROLOGUE 3627 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool_offset); 3628#endif 3629 3630 for (pool = first_pool; pool; pool = pool->next) 3631 { 3632 x = pool->constant; 3633 3634 if (! pool->mark) 3635 continue; 3636 3637 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF) 3638 whose CODE_LABEL has been deleted. This can occur if a jump table 3639 is eliminated by optimization. If so, write a constant of zero 3640 instead. Note that this can also happen by turning the 3641 CODE_LABEL into a NOTE. */ 3642 if (((GET_CODE (x) == LABEL_REF 3643 && (INSN_DELETED_P (XEXP (x, 0)) 3644 || GET_CODE (XEXP (x, 0)) == NOTE))) 3645 || (GET_CODE (x) == CONST && GET_CODE (XEXP (x, 0)) == PLUS 3646 && GET_CODE (XEXP (XEXP (x, 0), 0)) == LABEL_REF 3647 && (INSN_DELETED_P (XEXP (XEXP (XEXP (x, 0), 0), 0)) 3648 || GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 0)) == NOTE))) 3649 x = const0_rtx; 3650 3651 /* First switch to correct section. */ 3652#ifdef SELECT_RTX_SECTION 3653 SELECT_RTX_SECTION (pool->mode, x); 3654#else 3655 readonly_data_section (); 3656#endif 3657 3658#ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY 3659 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, pool->mode, 3660 pool->align, pool->labelno, done); 3661#endif 3662 3663 if (pool->align > 1) 3664 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (pool->align)); 3665 3666 /* Output the label. */ 3667 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", pool->labelno); 3668 3669 /* Output the value of the constant itself. */ 3670 switch (GET_MODE_CLASS (pool->mode)) 3671 { 3672 case MODE_FLOAT: 3673 if (GET_CODE (x) != CONST_DOUBLE) 3674 abort (); 3675 3676 bcopy ((char *) &CONST_DOUBLE_LOW (x), (char *) &u, sizeof u); 3677 assemble_real (u.d, pool->mode); 3678 break; 3679 3680 case MODE_INT: 3681 case MODE_PARTIAL_INT: 3682 assemble_integer (x, GET_MODE_SIZE (pool->mode), 1); 3683 break; 3684 3685 default: 3686 abort (); 3687 } 3688 3689#ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY 3690 done: ; 3691#endif 3692 3693 } 3694 3695#ifdef ASM_OUTPUT_POOL_EPILOGUE 3696 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool_offset); 3697#endif 3698 3699 /* Done with this pool. */ 3700 first_pool = last_pool = 0; 3701} 3702 3703/* Look through the instructions for this function, and mark all the 3704 entries in the constant pool which are actually being used. */ 3705 3706static void 3707mark_constant_pool () 3708{ 3709 register rtx insn; 3710 struct pool_constant *pool; 3711 3712 if (first_pool == 0) 3713 return; 3714 3715 for (pool = first_pool; pool; pool = pool->next) 3716 pool->mark = 0; 3717 3718 for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) 3719 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i') 3720 mark_constants (PATTERN (insn)); 3721 3722 for (insn = current_function_epilogue_delay_list; 3723 insn; 3724 insn = XEXP (insn, 1)) 3725 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i') 3726 mark_constants (PATTERN (insn)); 3727 3728 /* It's possible that the only reference to a symbol is in a symbol 3729 that's in the constant pool. This happens in Fortran under some 3730 situations. (When the constant contains the address of another 3731 constant, and only the first is used directly in an insn.) 3732 This is potentially suboptimal if there's ever a possibility of 3733 backwards (in pool order) 2'd level references. However, it's 3734 not clear that 2'd level references can happen. */ 3735 for (pool = first_pool; pool; pool = pool->next) 3736 { 3737 struct pool_sym *sym; 3738 char *label; 3739 3740 /* skip unmarked entries; no insn refers to them. */ 3741 if (!pool->mark) 3742 continue; 3743 3744 label = XSTR (pool->constant, 0); 3745 3746 /* Be sure the symbol's value is marked. */ 3747 for (sym = const_rtx_sym_hash_table[SYMHASH (label)]; sym; 3748 sym = sym->next) 3749 if (sym->label == label) 3750 sym->pool->mark = 1; 3751 /* If we didn't find it, there's something truly wrong here, but it 3752 will be announced by the assembler. */ 3753 } 3754} 3755 3756static void 3757mark_constants (x) 3758 register rtx x; 3759{ 3760 register int i; 3761 register char *format_ptr; 3762 3763 if (x == 0) 3764 return; 3765 3766 if (GET_CODE (x) == SYMBOL_REF) 3767 { 3768 if (CONSTANT_POOL_ADDRESS_P (x)) 3769 find_pool_constant (x)->mark = 1; 3770 return; 3771 } 3772 /* Never search inside a CONST_DOUBLE, because CONST_DOUBLE_MEM may be 3773 a MEM, but does not constitute a use of that MEM. This is particularly 3774 important inside a nested function, because CONST_DOUBLE_MEM may be 3775 a reference to a MEM in the parent's constant pool. See the comment 3776 in force_const_mem. */ 3777 else if (GET_CODE (x) == CONST_DOUBLE) 3778 return; 3779 3780 /* Insns may appear inside a SEQUENCE. Only check the patterns of 3781 insns, not any notes that may be attached. We don't want to mark 3782 a constant just because it happens to appear in a REG_EQUIV note. */ 3783 if (GET_RTX_CLASS (GET_CODE (x)) == 'i') 3784 { 3785 mark_constants (PATTERN (x)); 3786 return; 3787 } 3788 3789 format_ptr = GET_RTX_FORMAT (GET_CODE (x)); 3790 3791 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (x)); i++) 3792 { 3793 switch (*format_ptr++) 3794 { 3795 case 'e': 3796 mark_constants (XEXP (x, i)); 3797 break; 3798 3799 case 'E': 3800 if (XVEC (x, i) != 0) 3801 { 3802 register int j; 3803 3804 for (j = 0; j < XVECLEN (x, i); j++) 3805 mark_constants (XVECEXP (x, i, j)); 3806 } 3807 break; 3808 3809 case 'S': 3810 case 's': 3811 case '0': 3812 case 'i': 3813 case 'w': 3814 case 'n': 3815 case 'u': 3816 break; 3817 3818 default: 3819 abort (); 3820 } 3821 } 3822} 3823 3824/* Find all the constants whose addresses are referenced inside of EXP, 3825 and make sure assembler code with a label has been output for each one. 3826 Indicate whether an ADDR_EXPR has been encountered. */ 3827 3828static int 3829output_addressed_constants (exp) 3830 tree exp; 3831{ 3832 int reloc = 0; 3833 3834 switch (TREE_CODE (exp)) 3835 { 3836 case ADDR_EXPR: 3837 { 3838 register tree constant = TREE_OPERAND (exp, 0); 3839 3840 while (TREE_CODE (constant) == COMPONENT_REF) 3841 { 3842 constant = TREE_OPERAND (constant, 0); 3843 } 3844 3845 if (TREE_CODE_CLASS (TREE_CODE (constant)) == 'c' 3846 || TREE_CODE (constant) == CONSTRUCTOR) 3847 /* No need to do anything here 3848 for addresses of variables or functions. */ 3849 output_constant_def (constant); 3850 } 3851 reloc = 1; 3852 break; 3853 3854 case PLUS_EXPR: 3855 case MINUS_EXPR: 3856 reloc = output_addressed_constants (TREE_OPERAND (exp, 0)); 3857 reloc |= output_addressed_constants (TREE_OPERAND (exp, 1)); 3858 break; 3859 3860 case NOP_EXPR: 3861 case CONVERT_EXPR: 3862 case NON_LVALUE_EXPR: 3863 reloc = output_addressed_constants (TREE_OPERAND (exp, 0)); 3864 break; 3865 3866 case CONSTRUCTOR: 3867 { 3868 register tree link; 3869 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 3870 if (TREE_VALUE (link) != 0) 3871 reloc |= output_addressed_constants (TREE_VALUE (link)); 3872 } 3873 break; 3874 3875 default: 3876 break; 3877 } 3878 return reloc; 3879} 3880 3881/* Output assembler code for constant EXP to FILE, with no label. 3882 This includes the pseudo-op such as ".int" or ".byte", and a newline. 3883 Assumes output_addressed_constants has been done on EXP already. 3884 3885 Generate exactly SIZE bytes of assembler data, padding at the end 3886 with zeros if necessary. SIZE must always be specified. 3887 3888 SIZE is important for structure constructors, 3889 since trailing members may have been omitted from the constructor. 3890 It is also important for initialization of arrays from string constants 3891 since the full length of the string constant might not be wanted. 3892 It is also needed for initialization of unions, where the initializer's 3893 type is just one member, and that may not be as long as the union. 3894 3895 There a case in which we would fail to output exactly SIZE bytes: 3896 for a structure constructor that wants to produce more than SIZE bytes. 3897 But such constructors will never be generated for any possible input. */ 3898 3899void 3900output_constant (exp, size) 3901 register tree exp; 3902 register int size; 3903{ 3904 register enum tree_code code = TREE_CODE (TREE_TYPE (exp)); 3905 3906 /* Some front-ends use constants other than the standard 3907 language-indepdent varieties, but which may still be output 3908 directly. Give the front-end a chance to convert EXP to a 3909 language-independent representation. */ 3910 if (lang_expand_constant) 3911 exp = (*lang_expand_constant) (exp); 3912 3913 if (size == 0 || flag_syntax_only) 3914 return; 3915 3916 /* Eliminate the NON_LVALUE_EXPR_EXPR that makes a cast not be an lvalue. 3917 That way we get the constant (we hope) inside it. Also, strip off any 3918 NOP_EXPR that converts between two record, union, array, or set types. */ 3919 while ((TREE_CODE (exp) == NOP_EXPR 3920 && (TREE_TYPE (exp) == TREE_TYPE (TREE_OPERAND (exp, 0)) 3921 || AGGREGATE_TYPE_P (TREE_TYPE (exp)))) 3922 || TREE_CODE (exp) == NON_LVALUE_EXPR) 3923 exp = TREE_OPERAND (exp, 0); 3924 3925 /* Allow a constructor with no elements for any data type. 3926 This means to fill the space with zeros. */ 3927 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0) 3928 { 3929 assemble_zeros (size); 3930 return; 3931 } 3932 3933 switch (code) 3934 { 3935 case CHAR_TYPE: 3936 case BOOLEAN_TYPE: 3937 case INTEGER_TYPE: 3938 case ENUMERAL_TYPE: 3939 case POINTER_TYPE: 3940 case REFERENCE_TYPE: 3941 /* ??? What about (int)((float)(int)&foo + 4) */ 3942 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR 3943 || TREE_CODE (exp) == NON_LVALUE_EXPR) 3944 exp = TREE_OPERAND (exp, 0); 3945 3946 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode, 3947 EXPAND_INITIALIZER), 3948 size, 0)) 3949 error ("initializer for integer value is too complicated"); 3950 size = 0; 3951 break; 3952 3953 case REAL_TYPE: 3954 if (TREE_CODE (exp) != REAL_CST) 3955 error ("initializer for floating value is not a floating constant"); 3956 3957 assemble_real (TREE_REAL_CST (exp), 3958 mode_for_size (size * BITS_PER_UNIT, MODE_FLOAT, 0)); 3959 size = 0; 3960 break; 3961 3962 case COMPLEX_TYPE: 3963 output_constant (TREE_REALPART (exp), size / 2); 3964 output_constant (TREE_IMAGPART (exp), size / 2); 3965 size -= (size / 2) * 2; 3966 break; 3967 3968 case ARRAY_TYPE: 3969 if (TREE_CODE (exp) == CONSTRUCTOR) 3970 { 3971 output_constructor (exp, size); 3972 return; 3973 } 3974 else if (TREE_CODE (exp) == STRING_CST) 3975 { 3976 int excess = 0; 3977 3978 if (size > TREE_STRING_LENGTH (exp)) 3979 { 3980 excess = size - TREE_STRING_LENGTH (exp); 3981 size = TREE_STRING_LENGTH (exp); 3982 } 3983 3984 assemble_string (TREE_STRING_POINTER (exp), size); 3985 size = excess; 3986 } 3987 else 3988 abort (); 3989 break; 3990 3991 case RECORD_TYPE: 3992 case UNION_TYPE: 3993 if (TREE_CODE (exp) == CONSTRUCTOR) 3994 output_constructor (exp, size); 3995 else 3996 abort (); 3997 return; 3998 3999 case SET_TYPE: 4000 if (TREE_CODE (exp) == INTEGER_CST) 4001 assemble_integer (expand_expr (exp, NULL_RTX, 4002 VOIDmode, EXPAND_INITIALIZER), 4003 size, 1); 4004 else if (TREE_CODE (exp) == CONSTRUCTOR) 4005 { 4006 unsigned char *buffer = (unsigned char *) alloca (size); 4007 if (get_set_constructor_bytes (exp, buffer, size)) 4008 abort (); 4009 assemble_string ((char *) buffer, size); 4010 } 4011 else 4012 error ("unknown set constructor type"); 4013 return; 4014 4015 default: 4016 break; /* ??? */ 4017 } 4018 4019 if (size > 0) 4020 assemble_zeros (size); 4021} 4022 4023 4024/* Subroutine of output_constant, used for CONSTRUCTORs 4025 (aggregate constants). 4026 Generate at least SIZE bytes, padding if necessary. */ 4027 4028static void 4029output_constructor (exp, size) 4030 tree exp; 4031 int size; 4032{ 4033 register tree link, field = 0; 4034 HOST_WIDE_INT min_index = 0; 4035 /* Number of bytes output or skipped so far. 4036 In other words, current position within the constructor. */ 4037 int total_bytes = 0; 4038 /* Non-zero means BYTE contains part of a byte, to be output. */ 4039 int byte_buffer_in_use = 0; 4040 register int byte; 4041 4042 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT) 4043 abort (); 4044 4045 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) 4046 field = TYPE_FIELDS (TREE_TYPE (exp)); 4047 4048 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE 4049 && TYPE_DOMAIN (TREE_TYPE (exp)) != 0) 4050 min_index 4051 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (exp)))); 4052 4053 /* As LINK goes through the elements of the constant, 4054 FIELD goes through the structure fields, if the constant is a structure. 4055 if the constant is a union, then we override this, 4056 by getting the field from the TREE_LIST element. 4057 But the constant could also be an array. Then FIELD is zero. 4058 4059 There is always a maximum of one element in the chain LINK for unions 4060 (even if the initializer in a source program incorrectly contains 4061 more one). */ 4062 for (link = CONSTRUCTOR_ELTS (exp); 4063 link; 4064 link = TREE_CHAIN (link), 4065 field = field ? TREE_CHAIN (field) : 0) 4066 { 4067 tree val = TREE_VALUE (link); 4068 tree index = 0; 4069 4070 /* the element in a union constructor specifies the proper field. */ 4071 4072 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE 4073 || TREE_CODE (TREE_TYPE (exp)) == UNION_TYPE) 4074 { 4075 /* if available, use the type given by link */ 4076 if (TREE_PURPOSE (link) != 0) 4077 field = TREE_PURPOSE (link); 4078 } 4079 4080 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) 4081 index = TREE_PURPOSE (link); 4082 4083 /* Eliminate the marker that makes a cast not be an lvalue. */ 4084 if (val != 0) 4085 STRIP_NOPS (val); 4086 4087 if (index && TREE_CODE (index) == RANGE_EXPR) 4088 { 4089 register int fieldsize 4090 = int_size_in_bytes (TREE_TYPE (TREE_TYPE (exp))); 4091 HOST_WIDE_INT lo_index = TREE_INT_CST_LOW (TREE_OPERAND (index, 0)); 4092 HOST_WIDE_INT hi_index = TREE_INT_CST_LOW (TREE_OPERAND (index, 1)); 4093 HOST_WIDE_INT index; 4094 for (index = lo_index; index <= hi_index; index++) 4095 { 4096 /* Output the element's initial value. */ 4097 if (val == 0) 4098 assemble_zeros (fieldsize); 4099 else 4100 output_constant (val, fieldsize); 4101 4102 /* Count its size. */ 4103 total_bytes += fieldsize; 4104 } 4105 } 4106 else if (field == 0 || !DECL_BIT_FIELD (field)) 4107 { 4108 /* An element that is not a bit-field. */ 4109 4110 register int fieldsize; 4111 /* Since this structure is static, 4112 we know the positions are constant. */ 4113 int bitpos = (field ? (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field)) 4114 / BITS_PER_UNIT) 4115 : 0); 4116 if (index != 0) 4117 bitpos = (TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (val))) 4118 / BITS_PER_UNIT 4119 * (TREE_INT_CST_LOW (index) - min_index)); 4120 4121 /* Output any buffered-up bit-fields preceding this element. */ 4122 if (byte_buffer_in_use) 4123 { 4124 ASM_OUTPUT_BYTE (asm_out_file, byte); 4125 total_bytes++; 4126 byte_buffer_in_use = 0; 4127 } 4128 4129 /* Advance to offset of this element. 4130 Note no alignment needed in an array, since that is guaranteed 4131 if each element has the proper size. */ 4132 if ((field != 0 || index != 0) && bitpos != total_bytes) 4133 { 4134 assemble_zeros (bitpos - total_bytes); 4135 total_bytes = bitpos; 4136 } 4137 4138 /* Determine size this element should occupy. */ 4139 if (field) 4140 { 4141 if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST) 4142 abort (); 4143 if (TREE_INT_CST_LOW (DECL_SIZE (field)) > 100000) 4144 { 4145 /* This avoids overflow trouble. */ 4146 tree size_tree = size_binop (CEIL_DIV_EXPR, 4147 DECL_SIZE (field), 4148 size_int (BITS_PER_UNIT)); 4149 fieldsize = TREE_INT_CST_LOW (size_tree); 4150 } 4151 else 4152 { 4153 fieldsize = TREE_INT_CST_LOW (DECL_SIZE (field)); 4154 fieldsize = (fieldsize + BITS_PER_UNIT - 1) / BITS_PER_UNIT; 4155 } 4156 } 4157 else 4158 fieldsize = int_size_in_bytes (TREE_TYPE (TREE_TYPE (exp))); 4159 4160 /* Output the element's initial value. */ 4161 if (val == 0) 4162 assemble_zeros (fieldsize); 4163 else 4164 output_constant (val, fieldsize); 4165 4166 /* Count its size. */ 4167 total_bytes += fieldsize; 4168 } 4169 else if (val != 0 && TREE_CODE (val) != INTEGER_CST) 4170 error ("invalid initial value for member `%s'", 4171 IDENTIFIER_POINTER (DECL_NAME (field))); 4172 else 4173 { 4174 /* Element that is a bit-field. */ 4175 4176 int next_offset = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field)); 4177 int end_offset 4178 = (next_offset + TREE_INT_CST_LOW (DECL_SIZE (field))); 4179 4180 if (val == 0) 4181 val = integer_zero_node; 4182 4183 /* If this field does not start in this (or, next) byte, 4184 skip some bytes. */ 4185 if (next_offset / BITS_PER_UNIT != total_bytes) 4186 { 4187 /* Output remnant of any bit field in previous bytes. */ 4188 if (byte_buffer_in_use) 4189 { 4190 ASM_OUTPUT_BYTE (asm_out_file, byte); 4191 total_bytes++; 4192 byte_buffer_in_use = 0; 4193 } 4194 4195 /* If still not at proper byte, advance to there. */ 4196 if (next_offset / BITS_PER_UNIT != total_bytes) 4197 { 4198 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes); 4199 total_bytes = next_offset / BITS_PER_UNIT; 4200 } 4201 } 4202 4203 if (! byte_buffer_in_use) 4204 byte = 0; 4205 4206 /* We must split the element into pieces that fall within 4207 separate bytes, and combine each byte with previous or 4208 following bit-fields. */ 4209 4210 /* next_offset is the offset n fbits from the beginning of 4211 the structure to the next bit of this element to be processed. 4212 end_offset is the offset of the first bit past the end of 4213 this element. */ 4214 while (next_offset < end_offset) 4215 { 4216 int this_time; 4217 int shift; 4218 HOST_WIDE_INT value; 4219 int next_byte = next_offset / BITS_PER_UNIT; 4220 int next_bit = next_offset % BITS_PER_UNIT; 4221 4222 /* Advance from byte to byte 4223 within this element when necessary. */ 4224 while (next_byte != total_bytes) 4225 { 4226 ASM_OUTPUT_BYTE (asm_out_file, byte); 4227 total_bytes++; 4228 byte = 0; 4229 } 4230 4231 /* Number of bits we can process at once 4232 (all part of the same byte). */ 4233 this_time = MIN (end_offset - next_offset, 4234 BITS_PER_UNIT - next_bit); 4235 if (BYTES_BIG_ENDIAN) 4236 { 4237 /* On big-endian machine, take the most significant bits 4238 first (of the bits that are significant) 4239 and put them into bytes from the most significant end. */ 4240 shift = end_offset - next_offset - this_time; 4241 /* Don't try to take a bunch of bits that cross 4242 the word boundary in the INTEGER_CST. */ 4243 if (shift < HOST_BITS_PER_WIDE_INT 4244 && shift + this_time > HOST_BITS_PER_WIDE_INT) 4245 { 4246 this_time -= (HOST_BITS_PER_WIDE_INT - shift); 4247 shift = HOST_BITS_PER_WIDE_INT; 4248 } 4249 4250 /* Now get the bits from the appropriate constant word. */ 4251 if (shift < HOST_BITS_PER_WIDE_INT) 4252 { 4253 value = TREE_INT_CST_LOW (val); 4254 } 4255 else if (shift < 2 * HOST_BITS_PER_WIDE_INT) 4256 { 4257 value = TREE_INT_CST_HIGH (val); 4258 shift -= HOST_BITS_PER_WIDE_INT; 4259 } 4260 else 4261 abort (); 4262 byte |= (((value >> shift) 4263 & (((HOST_WIDE_INT) 1 << this_time) - 1)) 4264 << (BITS_PER_UNIT - this_time - next_bit)); 4265 } 4266 else 4267 { 4268 /* On little-endian machines, 4269 take first the least significant bits of the value 4270 and pack them starting at the least significant 4271 bits of the bytes. */ 4272 shift = (next_offset 4273 - TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field))); 4274 /* Don't try to take a bunch of bits that cross 4275 the word boundary in the INTEGER_CST. */ 4276 if (shift < HOST_BITS_PER_WIDE_INT 4277 && shift + this_time > HOST_BITS_PER_WIDE_INT) 4278 { 4279 this_time -= (HOST_BITS_PER_WIDE_INT - shift); 4280 shift = HOST_BITS_PER_WIDE_INT; 4281 } 4282 4283 /* Now get the bits from the appropriate constant word. */ 4284 if (shift < HOST_BITS_PER_WIDE_INT) 4285 value = TREE_INT_CST_LOW (val); 4286 else if (shift < 2 * HOST_BITS_PER_WIDE_INT) 4287 { 4288 value = TREE_INT_CST_HIGH (val); 4289 shift -= HOST_BITS_PER_WIDE_INT; 4290 } 4291 else 4292 abort (); 4293 byte |= (((value >> shift) 4294 & (((HOST_WIDE_INT) 1 << this_time) - 1)) 4295 << next_bit); 4296 } 4297 next_offset += this_time; 4298 byte_buffer_in_use = 1; 4299 } 4300 } 4301 } 4302 if (byte_buffer_in_use) 4303 { 4304 ASM_OUTPUT_BYTE (asm_out_file, byte); 4305 total_bytes++; 4306 } 4307 if (total_bytes < size) 4308 assemble_zeros (size - total_bytes); 4309} 4310 4311#ifdef HANDLE_PRAGMA_WEAK 4312/* Add function NAME to the weak symbols list. VALUE is a weak alias 4313 associatd with NAME. */ 4314 4315int 4316add_weak (name, value) 4317 char *name; 4318 char *value; 4319{ 4320 struct weak_syms *weak; 4321 4322 weak = (struct weak_syms *) permalloc (sizeof (struct weak_syms)); 4323 4324 if (weak == NULL) 4325 return 0; 4326 4327 weak->next = weak_decls; 4328 weak->name = name; 4329 weak->value = value; 4330 weak_decls = weak; 4331 4332 return 1; 4333} 4334#endif /* HANDLE_PRAGMA_WEAK */ 4335 4336/* Declare DECL to be a weak symbol. */ 4337 4338void 4339declare_weak (decl) 4340 tree decl; 4341{ 4342 if (! TREE_PUBLIC (decl)) 4343 error_with_decl (decl, "weak declaration of `%s' must be public"); 4344 else if (TREE_ASM_WRITTEN (decl)) 4345 error_with_decl (decl, "weak declaration of `%s' must precede definition"); 4346 else if (SUPPORTS_WEAK) 4347 DECL_WEAK (decl) = 1; 4348#ifdef HANDLE_PRAGMA_WEAK 4349 add_weak (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)), NULL); 4350#endif 4351} 4352 4353/* Emit any pending weak declarations. */ 4354 4355#ifdef HANDLE_PRAGMA_WEAK 4356struct weak_syms * weak_decls; 4357#endif 4358 4359void 4360weak_finish () 4361{ 4362#ifdef HANDLE_PRAGMA_WEAK 4363 if (HANDLE_PRAGMA_WEAK) 4364 { 4365 struct weak_syms *t; 4366 for (t = weak_decls; t; t = t->next) 4367 { 4368 if (t->name) 4369 { 4370 ASM_WEAKEN_LABEL (asm_out_file, t->name); 4371 if (t->value) 4372 ASM_OUTPUT_DEF (asm_out_file, t->name, t->value); 4373 } 4374 } 4375 } 4376#endif 4377} 4378 4379/* Remove NAME from the pending list of weak symbols. This prevents 4380 the compiler from emitting multiple .weak directives which confuses 4381 some assemblers. */ 4382static void 4383remove_from_pending_weak_list (name) 4384 char *name; 4385{ 4386#ifdef HANDLE_PRAGMA_WEAK 4387 if (HANDLE_PRAGMA_WEAK) 4388 { 4389 struct weak_syms *t; 4390 for (t = weak_decls; t; t = t->next) 4391 { 4392 if (t->name && strcmp (name, t->name) == 0) 4393 t->name = NULL; 4394 } 4395 } 4396#endif 4397} 4398 4399void 4400assemble_alias (decl, target) 4401 tree decl, target ATTRIBUTE_UNUSED; 4402{ 4403 char *name; 4404 4405 make_decl_rtl (decl, (char *) 0, 1); 4406 name = XSTR (XEXP (DECL_RTL (decl), 0), 0); 4407 4408#ifdef ASM_OUTPUT_DEF 4409 /* Make name accessible from other files, if appropriate. */ 4410 4411 if (TREE_PUBLIC (decl)) 4412 { 4413#ifdef ASM_WEAKEN_LABEL 4414 if (DECL_WEAK (decl)) 4415 { 4416 ASM_WEAKEN_LABEL (asm_out_file, name); 4417 /* Remove this function from the pending weak list so that 4418 we do not emit multiple .weak directives for it. */ 4419 remove_from_pending_weak_list 4420 (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl))); 4421 } 4422 else 4423#endif 4424 ASM_GLOBALIZE_LABEL (asm_out_file, name); 4425 } 4426 4427 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target)); 4428 TREE_ASM_WRITTEN (decl) = 1; 4429#else 4430#ifdef ASM_OUTPUT_WEAK_ALIAS 4431 if (! DECL_WEAK (decl)) 4432 warning ("only weak aliases are supported in this configuration"); 4433 4434 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target)); 4435 TREE_ASM_WRITTEN (decl) = 1; 4436#else 4437 warning ("alias definitions not supported in this configuration; ignored"); 4438#endif 4439#endif 4440} 4441 4442/* This determines whether or not we support link-once semantics. */ 4443#ifndef SUPPORTS_ONE_ONLY 4444#ifdef MAKE_DECL_ONE_ONLY 4445#define SUPPORTS_ONE_ONLY 1 4446#else 4447#define SUPPORTS_ONE_ONLY 0 4448#endif 4449#endif 4450 4451/* Returns 1 if the target configuration supports defining public symbols 4452 so that one of them will be chosen at link time instead of generating a 4453 multiply-defined symbol error, whether through the use of weak symbols or 4454 a target-specific mechanism for having duplicates discarded. */ 4455 4456int 4457supports_one_only () 4458{ 4459 if (SUPPORTS_ONE_ONLY) 4460 return 1; 4461 return SUPPORTS_WEAK; 4462} 4463 4464/* Set up DECL as a public symbol that can be defined in multiple 4465 translation units without generating a linker error. */ 4466 4467void 4468make_decl_one_only (decl) 4469 tree decl; 4470{ 4471 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL) 4472 abort (); 4473 4474 TREE_PUBLIC (decl) = 1; 4475 4476 if (TREE_CODE (decl) == VAR_DECL 4477 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node)) 4478 DECL_COMMON (decl) = 1; 4479 else if (SUPPORTS_ONE_ONLY) 4480 { 4481#ifdef MAKE_DECL_ONE_ONLY 4482 MAKE_DECL_ONE_ONLY (decl); 4483#endif 4484 DECL_ONE_ONLY (decl) = 1; 4485 } 4486 else if (SUPPORTS_WEAK) 4487 DECL_WEAK (decl) = 1; 4488 else 4489 abort (); 4490} 4491