varasm.c revision 50397
1/* Output variables, constants and external declarations, for GNU compiler. 2 Copyright (C) 1987, 88, 89, 92-97, 1998 Free Software Foundation, Inc. 3 4This file is part of GNU CC. 5 6GNU CC is free software; you can redistribute it and/or modify 7it under the terms of the GNU General Public License as published by 8the Free Software Foundation; either version 2, or (at your option) 9any later version. 10 11GNU CC is distributed in the hope that it will be useful, 12but WITHOUT ANY WARRANTY; without even the implied warranty of 13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14GNU General Public License for more details. 15 16You should have received a copy of the GNU General Public License 17along with GNU CC; see the file COPYING. If not, write to 18the Free Software Foundation, 59 Temple Place - Suite 330, 19Boston, MA 02111-1307, USA. */ 20 21 22/* This file handles generation of all the assembler code 23 *except* the instructions of a function. 24 This includes declarations of variables and their initial values. 25 26 We also output the assembler code for constants stored in memory 27 and are responsible for combining constants with the same value. */ 28 29#include "config.h" 30#include "system.h" 31#include <setjmp.h> 32/* #include <stab.h> */ 33#include "rtl.h" 34#include "tree.h" 35#include "flags.h" 36#include "except.h" 37#include "function.h" 38#include "expr.h" 39#include "output.h" 40#include "hard-reg-set.h" 41#include "regs.h" 42#include "defaults.h" 43#include "real.h" 44#include "toplev.h" 45#include "dbxout.h" 46#include "sdbout.h" 47 48#include "obstack.h" 49#include "c-pragma.h" 50 51#ifdef XCOFF_DEBUGGING_INFO 52#include "xcoffout.h" 53#endif 54 55#ifndef TRAMPOLINE_ALIGNMENT 56#define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY 57#endif 58 59#ifndef ASM_STABS_OP 60#define ASM_STABS_OP ".stabs" 61#endif 62 63/* Define the prefix to use when check_memory_usage_flag is enable. */ 64#ifdef NO_DOLLAR_IN_LABEL 65#ifdef NO_DOT_IN_LABEL 66#define CHKR_PREFIX "chkr_prefix_" 67#else /* !NO_DOT_IN_LABEL */ 68#define CHKR_PREFIX "chkr." 69#endif 70#else /* !NO_DOLLAR_IN_LABEL */ 71#define CHKR_PREFIX "chkr$" 72#endif 73#define CHKR_PREFIX_SIZE (sizeof (CHKR_PREFIX) - 1) 74 75/* This macro gets just the user-specified name 76 out of the string in a SYMBOL_REF. On most machines, 77 we discard the * if any and that's all. */ 78#ifndef STRIP_NAME_ENCODING 79#define STRIP_NAME_ENCODING(VAR,SYMBOL_NAME) \ 80 (VAR) = ((SYMBOL_NAME) + ((SYMBOL_NAME)[0] == '*')) 81#endif 82 83/* File in which assembler code is being written. */ 84 85extern FILE *asm_out_file; 86 87/* The (assembler) name of the first globally-visible object output. */ 88char *first_global_object_name; 89char *weak_global_object_name; 90 91extern struct obstack *current_obstack; 92extern struct obstack *saveable_obstack; 93extern struct obstack *rtl_obstack; 94extern struct obstack permanent_obstack; 95#define obstack_chunk_alloc xmalloc 96 97/* Number for making the label on the next 98 constant that is stored in memory. */ 99 100int const_labelno; 101 102/* Number for making the label on the next 103 static variable internal to a function. */ 104 105int var_labelno; 106 107/* Carry information from ASM_DECLARE_OBJECT_NAME 108 to ASM_FINISH_DECLARE_OBJECT. */ 109 110int size_directive_output; 111 112/* The last decl for which assemble_variable was called, 113 if it did ASM_DECLARE_OBJECT_NAME. 114 If the last call to assemble_variable didn't do that, 115 this holds 0. */ 116 117tree last_assemble_variable_decl; 118 119 120#ifdef HANDLE_PRAGMA_WEAK 121/* Any weak symbol declarations waiting to be emitted. */ 122 123struct weak_syms 124{ 125 struct weak_syms *next; 126 char *name; 127 char *value; 128}; 129 130static struct weak_syms *weak_decls; 131#endif 132 133/* Nonzero if at least one function definition has been seen. */ 134 135static int function_defined; 136 137struct addr_const; 138struct constant_descriptor; 139struct rtx_const; 140struct pool_constant; 141 142static char *strip_reg_name PROTO((char *)); 143static int contains_pointers_p PROTO((tree)); 144static void decode_addr_const PROTO((tree, struct addr_const *)); 145static int const_hash PROTO((tree)); 146static int compare_constant PROTO((tree, 147 struct constant_descriptor *)); 148static char *compare_constant_1 PROTO((tree, char *)); 149static struct constant_descriptor *record_constant PROTO((tree)); 150static void record_constant_1 PROTO((tree)); 151static tree copy_constant PROTO((tree)); 152static void output_constant_def_contents PROTO((tree, int, int)); 153static void decode_rtx_const PROTO((enum machine_mode, rtx, 154 struct rtx_const *)); 155static int const_hash_rtx PROTO((enum machine_mode, rtx)); 156static int compare_constant_rtx PROTO((enum machine_mode, rtx, 157 struct constant_descriptor *)); 158static struct constant_descriptor *record_constant_rtx PROTO((enum machine_mode, 159 rtx)); 160static struct pool_constant *find_pool_constant PROTO((rtx)); 161static void mark_constant_pool PROTO((void)); 162static void mark_constants PROTO((rtx)); 163static int output_addressed_constants PROTO((tree)); 164static void output_after_function_constants PROTO((void)); 165static void output_constructor PROTO((tree, int)); 166#ifdef ASM_OUTPUT_BSS 167static void asm_output_bss PROTO((FILE *, tree, char *, int, int)); 168#endif 169#ifdef BSS_SECTION_ASM_OP 170#ifdef ASM_OUTPUT_ALIGNED_BSS 171static void asm_output_aligned_bss PROTO((FILE *, tree, char *, int, int)); 172#endif 173#endif /* BSS_SECTION_ASM_OP */ 174 175static enum in_section { no_section, in_text, in_data, in_named 176#ifdef BSS_SECTION_ASM_OP 177 , in_bss 178#endif 179#ifdef EH_FRAME_SECTION_ASM_OP 180 , in_eh_frame 181#endif 182#ifdef EXTRA_SECTIONS 183 , EXTRA_SECTIONS 184#endif 185} in_section = no_section; 186 187/* Return a non-zero value if DECL has a section attribute. */ 188#define IN_NAMED_SECTION(DECL) \ 189 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \ 190 && DECL_SECTION_NAME (DECL) != NULL_TREE) 191 192/* Text of section name when in_section == in_named. */ 193static char *in_named_name; 194 195/* Define functions like text_section for any extra sections. */ 196#ifdef EXTRA_SECTION_FUNCTIONS 197EXTRA_SECTION_FUNCTIONS 198#endif 199 200/* Tell assembler to switch to text section. */ 201 202void 203text_section () 204{ 205 if (in_section != in_text) 206 { 207 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP); 208 in_section = in_text; 209 } 210} 211 212/* Tell assembler to switch to data section. */ 213 214void 215data_section () 216{ 217 if (in_section != in_data) 218 { 219 if (flag_shared_data) 220 { 221#ifdef SHARED_SECTION_ASM_OP 222 fprintf (asm_out_file, "%s\n", SHARED_SECTION_ASM_OP); 223#else 224 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP); 225#endif 226 } 227 else 228 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP); 229 230 in_section = in_data; 231 } 232} 233 234/* Tell assembler to switch to read-only data section. This is normally 235 the text section. */ 236 237void 238readonly_data_section () 239{ 240#ifdef READONLY_DATA_SECTION 241 READONLY_DATA_SECTION (); /* Note this can call data_section. */ 242#else 243 text_section (); 244#endif 245} 246 247/* Determine if we're in the text section. */ 248 249int 250in_text_section () 251{ 252 return in_section == in_text; 253} 254 255/* Determine if we're in the data section. */ 256 257int 258in_data_section () 259{ 260 return in_section == in_data; 261} 262 263/* Tell assembler to change to section NAME for DECL. 264 If DECL is NULL, just switch to section NAME. 265 If NAME is NULL, get the name from DECL. 266 If RELOC is 1, the initializer for DECL contains relocs. */ 267 268void 269named_section (decl, name, reloc) 270 tree decl; 271 char *name; 272 int reloc; 273{ 274 if (decl != NULL_TREE 275 && TREE_CODE_CLASS (TREE_CODE (decl)) != 'd') 276 abort (); 277 if (name == NULL) 278 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl)); 279 280 if (in_section != in_named || strcmp (name, in_named_name)) 281 { 282#ifdef ASM_OUTPUT_SECTION_NAME 283 ASM_OUTPUT_SECTION_NAME (asm_out_file, decl, name, reloc); 284#else 285 /* Section attributes are not supported if this macro isn't provided - 286 some host formats don't support them at all. The front-end should 287 already have flagged this as an error. */ 288 abort (); 289#endif 290 291 in_named_name = obstack_alloc (&permanent_obstack, strlen (name) + 1); 292 strcpy (in_named_name, name); 293 in_section = in_named; 294 } 295} 296 297#ifdef ASM_OUTPUT_SECTION_NAME 298#ifndef UNIQUE_SECTION 299#define UNIQUE_SECTION(DECL,RELOC) \ 300do { \ 301 int len; \ 302 char *name, *string; \ 303 \ 304 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (DECL)); \ 305 /* Strip off any encoding in name. */ \ 306 STRIP_NAME_ENCODING (name, name); \ 307 \ 308 len = strlen (name) + 1; \ 309 string = alloca (len + 1); \ 310 sprintf (string, ".%s", name); \ 311 \ 312 DECL_SECTION_NAME (DECL) = build_string (len, string); \ 313} while (0) 314#endif 315#ifndef UNIQUE_SECTION_P 316#define UNIQUE_SECTION_P(DECL) 0 317#endif 318#endif 319 320#ifdef BSS_SECTION_ASM_OP 321 322/* Tell the assembler to switch to the bss section. */ 323 324void 325bss_section () 326{ 327 if (in_section != in_bss) 328 { 329#ifdef SHARED_BSS_SECTION_ASM_OP 330 if (flag_shared_data) 331 fprintf (asm_out_file, "%s\n", SHARED_BSS_SECTION_ASM_OP); 332 else 333#endif 334 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP); 335 336 in_section = in_bss; 337 } 338} 339 340#ifdef ASM_OUTPUT_BSS 341 342/* Utility function for ASM_OUTPUT_BSS for targets to use if 343 they don't support alignments in .bss. 344 ??? It is believed that this function will work in most cases so such 345 support is localized here. */ 346 347static void 348asm_output_bss (file, decl, name, size, rounded) 349 FILE *file; 350 tree decl; 351 char *name; 352 int size, rounded; 353{ 354 ASM_GLOBALIZE_LABEL (file, name); 355 bss_section (); 356#ifdef ASM_DECLARE_OBJECT_NAME 357 last_assemble_variable_decl = decl; 358 ASM_DECLARE_OBJECT_NAME (file, name, decl); 359#else 360 /* Standard thing is just output label for the object. */ 361 ASM_OUTPUT_LABEL (file, name); 362#endif /* ASM_DECLARE_OBJECT_NAME */ 363 ASM_OUTPUT_SKIP (file, rounded); 364} 365 366#endif 367 368#ifdef ASM_OUTPUT_ALIGNED_BSS 369 370/* Utility function for targets to use in implementing 371 ASM_OUTPUT_ALIGNED_BSS. 372 ??? It is believed that this function will work in most cases so such 373 support is localized here. */ 374 375static void 376asm_output_aligned_bss (file, decl, name, size, align) 377 FILE *file; 378 tree decl; 379 char *name; 380 int size, align; 381{ 382 ASM_GLOBALIZE_LABEL (file, name); 383 bss_section (); 384 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT)); 385#ifdef ASM_DECLARE_OBJECT_NAME 386 last_assemble_variable_decl = decl; 387 ASM_DECLARE_OBJECT_NAME (file, name, decl); 388#else 389 /* Standard thing is just output label for the object. */ 390 ASM_OUTPUT_LABEL (file, name); 391#endif /* ASM_DECLARE_OBJECT_NAME */ 392 ASM_OUTPUT_SKIP (file, size ? size : 1); 393} 394 395#endif 396 397#endif /* BSS_SECTION_ASM_OP */ 398 399#ifdef EH_FRAME_SECTION_ASM_OP 400void 401eh_frame_section () 402{ 403 if (in_section != in_eh_frame) 404 { 405 fprintf (asm_out_file, "%s\n", EH_FRAME_SECTION_ASM_OP); 406 in_section = in_eh_frame; 407 } 408} 409#endif 410 411/* Switch to the section for function DECL. 412 413 If DECL is NULL_TREE, switch to the text section. 414 ??? It's not clear that we will ever be passed NULL_TREE, but it's 415 safer to handle it. */ 416 417void 418function_section (decl) 419 tree decl; 420{ 421 if (decl != NULL_TREE 422 && DECL_SECTION_NAME (decl) != NULL_TREE) 423 named_section (decl, (char *) 0, 0); 424 else 425 text_section (); 426} 427 428/* Switch to section for variable DECL. 429 430 RELOC is the `reloc' argument to SELECT_SECTION. */ 431 432void 433variable_section (decl, reloc) 434 tree decl; 435 int reloc; 436{ 437 if (IN_NAMED_SECTION (decl)) 438 named_section (decl, NULL, reloc); 439 else 440 { 441 /* C++ can have const variables that get initialized from constructors, 442 and thus can not be in a readonly section. We prevent this by 443 verifying that the initial value is constant for objects put in a 444 readonly section. 445 446 error_mark_node is used by the C front end to indicate that the 447 initializer has not been seen yet. In this case, we assume that 448 the initializer must be constant. 449 450 C++ uses error_mark_node for variables that have complicated 451 initializers, but these variables go in BSS so we won't be called 452 for them. */ 453 454#ifdef SELECT_SECTION 455 SELECT_SECTION (decl, reloc); 456#else 457 if (DECL_READONLY_SECTION (decl, reloc)) 458 readonly_data_section (); 459 else 460 data_section (); 461#endif 462 } 463} 464 465/* Tell assembler to switch to the section for the exception handling 466 table. */ 467 468void 469exception_section () 470{ 471#if defined (EXCEPTION_SECTION) 472 EXCEPTION_SECTION (); 473#else 474#ifdef ASM_OUTPUT_SECTION_NAME 475 named_section (NULL_TREE, ".gcc_except_table", 0); 476#else 477 if (flag_pic) 478 data_section (); 479 else 480 readonly_data_section (); 481#endif 482#endif 483} 484 485/* Create the rtl to represent a function, for a function definition. 486 DECL is a FUNCTION_DECL node which describes which function. 487 The rtl is stored into DECL. */ 488 489void 490make_function_rtl (decl) 491 tree decl; 492{ 493 char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 494 char *new_name = name; 495 496 /* Rename a nested function to avoid conflicts. */ 497 if (decl_function_context (decl) != 0 498 && DECL_INITIAL (decl) != 0 499 && DECL_RTL (decl) == 0) 500 { 501 char *label; 502 503 name = IDENTIFIER_POINTER (DECL_NAME (decl)); 504 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno); 505 name = obstack_copy0 (saveable_obstack, label, strlen (label)); 506 var_labelno++; 507 } 508 else 509 { 510 /* When -fprefix-function-name is used, every function name is 511 prefixed. Even static functions are prefixed because they 512 could be declared latter. Note that a nested function name 513 is not prefixed. */ 514 if (flag_prefix_function_name) 515 { 516 new_name = (char *) alloca (strlen (name) + CHKR_PREFIX_SIZE + 1); 517 strcpy (new_name, CHKR_PREFIX); 518 strcpy (new_name + CHKR_PREFIX_SIZE, name); 519 name = obstack_copy0 (saveable_obstack, new_name, strlen (new_name)); 520 } 521 } 522 523 if (DECL_RTL (decl) == 0) 524 { 525 DECL_RTL (decl) 526 = gen_rtx_MEM (DECL_MODE (decl), 527 gen_rtx_SYMBOL_REF (Pmode, name)); 528 529 /* Optionally set flags or add text to the name to record information 530 such as that it is a function name. If the name is changed, the macro 531 ASM_OUTPUT_LABELREF will have to know how to strip this information. */ 532#ifdef ENCODE_SECTION_INFO 533 ENCODE_SECTION_INFO (decl); 534#endif 535 } 536 else 537 { 538 /* ??? Another way to do this would be to do what halfpic.c does 539 and maintain a hashed table of such critters. */ 540 /* ??? Another way to do this would be to pass a flag bit to 541 ENCODE_SECTION_INFO saying whether this is a new decl or not. */ 542 /* Let the target reassign the RTL if it wants. 543 This is necessary, for example, when one machine specific 544 decl attribute overrides another. */ 545#ifdef REDO_SECTION_INFO_P 546 if (REDO_SECTION_INFO_P (decl)) 547 ENCODE_SECTION_INFO (decl); 548#endif 549 } 550 551 /* Record at least one function has been defined. */ 552 function_defined = 1; 553} 554 555/* Given NAME, a putative register name, discard any customary prefixes. */ 556 557static char * 558strip_reg_name (name) 559 char *name; 560{ 561#ifdef REGISTER_PREFIX 562 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX))) 563 name += strlen (REGISTER_PREFIX); 564#endif 565 if (name[0] == '%' || name[0] == '#') 566 name++; 567 return name; 568} 569 570/* Decode an `asm' spec for a declaration as a register name. 571 Return the register number, or -1 if nothing specified, 572 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized, 573 or -3 if ASMSPEC is `cc' and is not recognized, 574 or -4 if ASMSPEC is `memory' and is not recognized. 575 Accept an exact spelling or a decimal number. 576 Prefixes such as % are optional. */ 577 578int 579decode_reg_name (asmspec) 580 char *asmspec; 581{ 582 if (asmspec != 0) 583 { 584 int i; 585 586 /* Get rid of confusing prefixes. */ 587 asmspec = strip_reg_name (asmspec); 588 589 /* Allow a decimal number as a "register name". */ 590 for (i = strlen (asmspec) - 1; i >= 0; i--) 591 if (! (asmspec[i] >= '0' && asmspec[i] <= '9')) 592 break; 593 if (asmspec[0] != 0 && i < 0) 594 { 595 i = atoi (asmspec); 596 if (i < FIRST_PSEUDO_REGISTER && i >= 0) 597 return i; 598 else 599 return -2; 600 } 601 602 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) 603 if (reg_names[i][0] 604 && ! strcmp (asmspec, strip_reg_name (reg_names[i]))) 605 return i; 606 607#ifdef ADDITIONAL_REGISTER_NAMES 608 { 609 static struct { char *name; int number; } table[] 610 = ADDITIONAL_REGISTER_NAMES; 611 612 for (i = 0; i < sizeof (table) / sizeof (table[0]); i++) 613 if (! strcmp (asmspec, table[i].name)) 614 return table[i].number; 615 } 616#endif /* ADDITIONAL_REGISTER_NAMES */ 617 618 if (!strcmp (asmspec, "memory")) 619 return -4; 620 621 if (!strcmp (asmspec, "cc")) 622 return -3; 623 624 return -2; 625 } 626 627 return -1; 628} 629 630/* Create the DECL_RTL for a declaration for a static or external variable 631 or static or external function. 632 ASMSPEC, if not 0, is the string which the user specified 633 as the assembler symbol name. 634 TOP_LEVEL is nonzero if this is a file-scope variable. 635 636 This is never called for PARM_DECL nodes. */ 637 638void 639make_decl_rtl (decl, asmspec, top_level) 640 tree decl; 641 char *asmspec; 642 int top_level; 643{ 644 register char *name = 0; 645 int reg_number; 646 647 reg_number = decode_reg_name (asmspec); 648 649 if (DECL_ASSEMBLER_NAME (decl) != NULL_TREE) 650 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); 651 652 if (reg_number == -2) 653 { 654 /* ASMSPEC is given, and not the name of a register. */ 655 name = (char *) obstack_alloc (saveable_obstack, 656 strlen (asmspec) + 2); 657 name[0] = '*'; 658 strcpy (&name[1], asmspec); 659 } 660 661 /* For a duplicate declaration, we can be called twice on the 662 same DECL node. Don't discard the RTL already made. */ 663 if (DECL_RTL (decl) == 0) 664 { 665 /* First detect errors in declaring global registers. */ 666 if (TREE_CODE (decl) != FUNCTION_DECL 667 && DECL_REGISTER (decl) && reg_number == -1) 668 error_with_decl (decl, 669 "register name not specified for `%s'"); 670 else if (TREE_CODE (decl) != FUNCTION_DECL 671 && DECL_REGISTER (decl) && reg_number < 0) 672 error_with_decl (decl, 673 "invalid register name for `%s'"); 674 else if ((reg_number >= 0 || reg_number == -3) 675 && (TREE_CODE (decl) == FUNCTION_DECL 676 && ! DECL_REGISTER (decl))) 677 error_with_decl (decl, 678 "register name given for non-register variable `%s'"); 679 else if (TREE_CODE (decl) != FUNCTION_DECL 680 && DECL_REGISTER (decl) 681 && TYPE_MODE (TREE_TYPE (decl)) == BLKmode) 682 error_with_decl (decl, 683 "data type of `%s' isn't suitable for a register"); 684 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl) 685 && ! HARD_REGNO_MODE_OK (reg_number, 686 TYPE_MODE (TREE_TYPE (decl)))) 687 error_with_decl (decl, 688 "register number for `%s' isn't suitable for data type"); 689 /* Now handle properly declared static register variables. */ 690 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl)) 691 { 692 int nregs; 693 694 if (DECL_INITIAL (decl) != 0 && top_level) 695 { 696 DECL_INITIAL (decl) = 0; 697 error ("global register variable has initial value"); 698 } 699 if (fixed_regs[reg_number] == 0 700 && function_defined && top_level) 701 error ("global register variable follows a function definition"); 702 if (TREE_THIS_VOLATILE (decl)) 703 warning ("volatile register variables don't work as you might wish"); 704 705 /* If the user specified one of the eliminables registers here, 706 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable 707 confused with that register and be eliminated. Although this 708 usage is somewhat suspect, we nevertheless use the following 709 kludge to avoid setting DECL_RTL to frame_pointer_rtx. */ 710 711 DECL_RTL (decl) 712 = gen_rtx_REG (DECL_MODE (decl), FIRST_PSEUDO_REGISTER); 713 REGNO (DECL_RTL (decl)) = reg_number; 714 REG_USERVAR_P (DECL_RTL (decl)) = 1; 715 716 if (top_level) 717 { 718 /* Make this register global, so not usable for anything 719 else. */ 720 nregs = HARD_REGNO_NREGS (reg_number, DECL_MODE (decl)); 721 while (nregs > 0) 722 globalize_reg (reg_number + --nregs); 723 } 724 } 725 /* Specifying a section attribute on a variable forces it into a 726 non-.bss section, and thus it cannot be common. */ 727 else if (TREE_CODE (decl) == VAR_DECL 728 && DECL_SECTION_NAME (decl) != NULL_TREE 729 && DECL_INITIAL (decl) == NULL_TREE 730 && DECL_COMMON (decl)) 731 DECL_COMMON (decl) = 0; 732 733 /* Now handle ordinary static variables and functions (in memory). 734 Also handle vars declared register invalidly. */ 735 if (DECL_RTL (decl) == 0) 736 { 737 /* Can't use just the variable's own name for a variable 738 whose scope is less than the whole file. 739 Concatenate a distinguishing number. */ 740 if (!top_level && !TREE_PUBLIC (decl) && asmspec == 0) 741 { 742 char *label; 743 744 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno); 745 name = obstack_copy0 (saveable_obstack, label, strlen (label)); 746 var_labelno++; 747 } 748 749 if (name == 0) 750 abort (); 751 752 /* When -fprefix-function-name is used, the functions 753 names are prefixed. Only nested function names are not 754 prefixed. */ 755 if (flag_prefix_function_name && TREE_CODE (decl) == FUNCTION_DECL) 756 { 757 char *new_name; 758 new_name = (char *) alloca (strlen (name) + CHKR_PREFIX_SIZE 759 + 1); 760 strcpy (new_name, CHKR_PREFIX); 761 strcpy (new_name + CHKR_PREFIX_SIZE, name); 762 name = obstack_copy0 (saveable_obstack, 763 new_name, strlen (new_name)); 764 } 765 766 DECL_RTL (decl) = gen_rtx_MEM (DECL_MODE (decl), 767 gen_rtx_SYMBOL_REF (Pmode, name)); 768 MEM_ALIAS_SET (DECL_RTL (decl)) = get_alias_set (decl); 769 770 /* If this variable is to be treated as volatile, show its 771 tree node has side effects. If it has side effects, either 772 because of this test or from TREE_THIS_VOLATILE also 773 being set, show the MEM is volatile. */ 774 if (flag_volatile_global && TREE_CODE (decl) == VAR_DECL 775 && TREE_PUBLIC (decl)) 776 TREE_SIDE_EFFECTS (decl) = 1; 777 if (TREE_SIDE_EFFECTS (decl)) 778 MEM_VOLATILE_P (DECL_RTL (decl)) = 1; 779 780 if (TREE_READONLY (decl)) 781 RTX_UNCHANGING_P (DECL_RTL (decl)) = 1; 782 MEM_IN_STRUCT_P (DECL_RTL (decl)) 783 = AGGREGATE_TYPE_P (TREE_TYPE (decl)); 784 785 /* Optionally set flags or add text to the name to record information 786 such as that it is a function name. 787 If the name is changed, the macro ASM_OUTPUT_LABELREF 788 will have to know how to strip this information. */ 789#ifdef ENCODE_SECTION_INFO 790 ENCODE_SECTION_INFO (decl); 791#endif 792 } 793 } 794 else 795 { 796 /* If the old RTL had the wrong mode, fix the mode. */ 797 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl)) 798 { 799 rtx rtl = DECL_RTL (decl); 800 PUT_MODE (rtl, DECL_MODE (decl)); 801 } 802 803 /* ??? Another way to do this would be to do what halfpic.c does 804 and maintain a hashed table of such critters. */ 805 /* ??? Another way to do this would be to pass a flag bit to 806 ENCODE_SECTION_INFO saying whether this is a new decl or not. */ 807 /* Let the target reassign the RTL if it wants. 808 This is necessary, for example, when one machine specific 809 decl attribute overrides another. */ 810#ifdef REDO_SECTION_INFO_P 811 if (REDO_SECTION_INFO_P (decl)) 812 ENCODE_SECTION_INFO (decl); 813#endif 814 } 815} 816 817/* Make the rtl for variable VAR be volatile. 818 Use this only for static variables. */ 819 820void 821make_var_volatile (var) 822 tree var; 823{ 824 if (GET_CODE (DECL_RTL (var)) != MEM) 825 abort (); 826 827 MEM_VOLATILE_P (DECL_RTL (var)) = 1; 828} 829 830/* Output alignment directive to align for constant expression EXP. */ 831 832void 833assemble_constant_align (exp) 834 tree exp; 835{ 836 int align; 837 838 /* Align the location counter as required by EXP's data type. */ 839 align = TYPE_ALIGN (TREE_TYPE (exp)); 840#ifdef CONSTANT_ALIGNMENT 841 align = CONSTANT_ALIGNMENT (exp, align); 842#endif 843 844 if (align > BITS_PER_UNIT) 845 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 846} 847 848/* Output a string of literal assembler code 849 for an `asm' keyword used between functions. */ 850 851void 852assemble_asm (string) 853 tree string; 854{ 855 app_enable (); 856 857 if (TREE_CODE (string) == ADDR_EXPR) 858 string = TREE_OPERAND (string, 0); 859 860 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string)); 861} 862 863#if 0 /* This should no longer be needed, because 864 flag_gnu_linker should be 0 on these systems, 865 which should prevent any output 866 if ASM_OUTPUT_CONSTRUCTOR and ASM_OUTPUT_DESTRUCTOR are absent. */ 867#if !(defined(DBX_DEBUGGING_INFO) && !defined(FASCIST_ASSEMBLER)) 868#ifndef ASM_OUTPUT_CONSTRUCTOR 869#define ASM_OUTPUT_CONSTRUCTOR(file, name) 870#endif 871#ifndef ASM_OUTPUT_DESTRUCTOR 872#define ASM_OUTPUT_DESTRUCTOR(file, name) 873#endif 874#endif 875#endif /* 0 */ 876 877/* Record an element in the table of global destructors. 878 How this is done depends on what sort of assembler and linker 879 are in use. 880 881 NAME should be the name of a global function to be called 882 at exit time. This name is output using assemble_name. */ 883 884void 885assemble_destructor (name) 886 char *name; 887{ 888#ifdef ASM_OUTPUT_DESTRUCTOR 889 ASM_OUTPUT_DESTRUCTOR (asm_out_file, name); 890#else 891 if (flag_gnu_linker) 892 { 893 /* Now tell GNU LD that this is part of the static destructor set. */ 894 /* This code works for any machine provided you use GNU as/ld. */ 895 fprintf (asm_out_file, "%s \"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP); 896 assemble_name (asm_out_file, name); 897 fputc ('\n', asm_out_file); 898 } 899#endif 900} 901 902/* Likewise for global constructors. */ 903 904void 905assemble_constructor (name) 906 char *name; 907{ 908#ifdef ASM_OUTPUT_CONSTRUCTOR 909 ASM_OUTPUT_CONSTRUCTOR (asm_out_file, name); 910#else 911 if (flag_gnu_linker) 912 { 913 /* Now tell GNU LD that this is part of the static constructor set. */ 914 /* This code works for any machine provided you use GNU as/ld. */ 915 fprintf (asm_out_file, "%s \"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP); 916 assemble_name (asm_out_file, name); 917 fputc ('\n', asm_out_file); 918 } 919#endif 920} 921 922/* Likewise for entries we want to record for garbage collection. 923 Garbage collection is still under development. */ 924 925void 926assemble_gc_entry (name) 927 char *name; 928{ 929#ifdef ASM_OUTPUT_GC_ENTRY 930 ASM_OUTPUT_GC_ENTRY (asm_out_file, name); 931#else 932 if (flag_gnu_linker) 933 { 934 /* Now tell GNU LD that this is part of the static constructor set. */ 935 fprintf (asm_out_file, "%s \"___PTR_LIST__\",22,0,0,", ASM_STABS_OP); 936 assemble_name (asm_out_file, name); 937 fputc ('\n', asm_out_file); 938 } 939#endif 940} 941 942/* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with 943 a non-zero value if the constant pool should be output before the 944 start of the function, or a zero value if the pool should output 945 after the end of the function. The default is to put it before the 946 start. */ 947 948#ifndef CONSTANT_POOL_BEFORE_FUNCTION 949#define CONSTANT_POOL_BEFORE_FUNCTION 1 950#endif 951 952/* Output assembler code for the constant pool of a function and associated 953 with defining the name of the function. DECL describes the function. 954 NAME is the function's name. For the constant pool, we use the current 955 constant pool data. */ 956 957void 958assemble_start_function (decl, fnname) 959 tree decl; 960 char *fnname; 961{ 962 int align; 963 964 /* The following code does not need preprocessing in the assembler. */ 965 966 app_disable (); 967 968 if (CONSTANT_POOL_BEFORE_FUNCTION) 969 output_constant_pool (fnname, decl); 970 971#ifdef ASM_OUTPUT_SECTION_NAME 972 /* If the function is to be put in its own section and it's not in a section 973 already, indicate so. */ 974 if ((flag_function_sections 975 && DECL_SECTION_NAME (decl) == NULL_TREE) 976 || UNIQUE_SECTION_P (decl)) 977 UNIQUE_SECTION (decl, 0); 978#endif 979 980 function_section (decl); 981 982 /* Tell assembler to move to target machine's alignment for functions. */ 983 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT); 984 if (align > 0) 985 ASM_OUTPUT_ALIGN (asm_out_file, align); 986 987#ifdef ASM_OUTPUT_FUNCTION_PREFIX 988 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname); 989#endif 990 991#ifdef SDB_DEBUGGING_INFO 992 /* Output SDB definition of the function. */ 993 if (write_symbols == SDB_DEBUG) 994 sdbout_mark_begin_function (); 995#endif 996 997#ifdef DBX_DEBUGGING_INFO 998 /* Output DBX definition of the function. */ 999 if (write_symbols == DBX_DEBUG) 1000 dbxout_begin_function (decl); 1001#endif 1002 1003 /* Make function name accessible from other files, if appropriate. */ 1004 1005 if (TREE_PUBLIC (decl)) 1006 { 1007 if (! first_global_object_name) 1008 { 1009 char *p; 1010 char **name; 1011 1012 if (! DECL_WEAK (decl) && ! DECL_ONE_ONLY (decl)) 1013 name = &first_global_object_name; 1014 else 1015 name = &weak_global_object_name; 1016 1017 STRIP_NAME_ENCODING (p, fnname); 1018 *name = permalloc (strlen (p) + 1); 1019 strcpy (*name, p); 1020 } 1021 1022#ifdef ASM_WEAKEN_LABEL 1023 if (DECL_WEAK (decl)) 1024 ASM_WEAKEN_LABEL (asm_out_file, fnname); 1025 else 1026#endif 1027 ASM_GLOBALIZE_LABEL (asm_out_file, fnname); 1028 } 1029 1030 /* Do any machine/system dependent processing of the function name */ 1031#ifdef ASM_DECLARE_FUNCTION_NAME 1032 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl); 1033#else 1034 /* Standard thing is just output label for the function. */ 1035 ASM_OUTPUT_LABEL (asm_out_file, fnname); 1036#endif /* ASM_DECLARE_FUNCTION_NAME */ 1037} 1038 1039/* Output assembler code associated with defining the size of the 1040 function. DECL describes the function. NAME is the function's name. */ 1041 1042void 1043assemble_end_function (decl, fnname) 1044 tree decl; 1045 char *fnname; 1046{ 1047#ifdef ASM_DECLARE_FUNCTION_SIZE 1048 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl); 1049#endif 1050 if (! CONSTANT_POOL_BEFORE_FUNCTION) 1051 { 1052 output_constant_pool (fnname, decl); 1053 function_section (decl); /* need to switch back */ 1054 } 1055 1056 /* Output any constants which should appear after the function. */ 1057 output_after_function_constants (); 1058} 1059 1060/* Assemble code to leave SIZE bytes of zeros. */ 1061 1062void 1063assemble_zeros (size) 1064 int size; 1065{ 1066#ifdef ASM_NO_SKIP_IN_TEXT 1067 /* The `space' pseudo in the text section outputs nop insns rather than 0s, 1068 so we must output 0s explicitly in the text section. */ 1069 if (ASM_NO_SKIP_IN_TEXT && in_text_section ()) 1070 { 1071 int i; 1072 1073 for (i = 0; i < size - 20; i += 20) 1074 { 1075#ifdef ASM_BYTE_OP 1076 fprintf (asm_out_file, 1077 "%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); 1078#else 1079 fprintf (asm_out_file, 1080 "\tbyte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0\n"); 1081#endif 1082 } 1083 if (i < size) 1084 { 1085#ifdef ASM_BYTE_OP 1086 fprintf (asm_out_file, "%s 0", ASM_BYTE_OP); 1087#else 1088 fprintf (asm_out_file, "\tbyte 0"); 1089#endif 1090 i++; 1091 for (; i < size; i++) 1092 fprintf (asm_out_file, ",0"); 1093 fprintf (asm_out_file, "\n"); 1094 } 1095 } 1096 else 1097#endif 1098 if (size > 0) 1099 ASM_OUTPUT_SKIP (asm_out_file, size); 1100} 1101 1102/* Assemble an alignment pseudo op for an ALIGN-bit boundary. */ 1103 1104void 1105assemble_align (align) 1106 int align; 1107{ 1108 if (align > BITS_PER_UNIT) 1109 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 1110} 1111 1112/* Assemble a string constant with the specified C string as contents. */ 1113 1114void 1115assemble_string (p, size) 1116 char *p; 1117 int size; 1118{ 1119 int pos = 0; 1120 int maximum = 2000; 1121 1122 /* If the string is very long, split it up. */ 1123 1124 while (pos < size) 1125 { 1126 int thissize = size - pos; 1127 if (thissize > maximum) 1128 thissize = maximum; 1129 1130 ASM_OUTPUT_ASCII (asm_out_file, p, thissize); 1131 1132 pos += thissize; 1133 p += thissize; 1134 } 1135} 1136 1137 1138/* Assemble everything that is needed for a variable or function declaration. 1139 Not used for automatic variables, and not used for function definitions. 1140 Should not be called for variables of incomplete structure type. 1141 1142 TOP_LEVEL is nonzero if this variable has file scope. 1143 AT_END is nonzero if this is the special handling, at end of compilation, 1144 to define things that have had only tentative definitions. 1145 DONT_OUTPUT_DATA if nonzero means don't actually output the 1146 initial value (that will be done by the caller). */ 1147 1148void 1149assemble_variable (decl, top_level, at_end, dont_output_data) 1150 tree decl; 1151 int top_level; 1152 int at_end; 1153 int dont_output_data; 1154{ 1155 register char *name; 1156 unsigned int align; 1157 tree size_tree; 1158 int reloc = 0; 1159 enum in_section saved_in_section; 1160 1161 last_assemble_variable_decl = 0; 1162 1163 if (GET_CODE (DECL_RTL (decl)) == REG) 1164 { 1165 /* Do output symbol info for global register variables, but do nothing 1166 else for them. */ 1167 1168 if (TREE_ASM_WRITTEN (decl)) 1169 return; 1170 TREE_ASM_WRITTEN (decl) = 1; 1171 1172#if defined (DBX_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO) 1173 /* File-scope global variables are output here. */ 1174 if ((write_symbols == DBX_DEBUG || write_symbols == XCOFF_DEBUG) 1175 && top_level) 1176 dbxout_symbol (decl, 0); 1177#endif 1178#ifdef SDB_DEBUGGING_INFO 1179 if (write_symbols == SDB_DEBUG && top_level 1180 /* Leave initialized global vars for end of compilation; 1181 see comment in compile_file. */ 1182 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0)) 1183 sdbout_symbol (decl, 0); 1184#endif 1185 1186 /* Don't output any DWARF debugging information for variables here. 1187 In the case of local variables, the information for them is output 1188 when we do our recursive traversal of the tree representation for 1189 the entire containing function. In the case of file-scope variables, 1190 we output information for all of them at the very end of compilation 1191 while we are doing our final traversal of the chain of file-scope 1192 declarations. */ 1193 1194 return; 1195 } 1196 1197 /* Normally no need to say anything here for external references, 1198 since assemble_external is called by the language-specific code 1199 when a declaration is first seen. */ 1200 1201 if (DECL_EXTERNAL (decl)) 1202 return; 1203 1204 /* Output no assembler code for a function declaration. 1205 Only definitions of functions output anything. */ 1206 1207 if (TREE_CODE (decl) == FUNCTION_DECL) 1208 return; 1209 1210 /* If type was incomplete when the variable was declared, 1211 see if it is complete now. */ 1212 1213 if (DECL_SIZE (decl) == 0) 1214 layout_decl (decl, 0); 1215 1216 /* Still incomplete => don't allocate it; treat the tentative defn 1217 (which is what it must have been) as an `extern' reference. */ 1218 1219 if (!dont_output_data && DECL_SIZE (decl) == 0) 1220 { 1221 error_with_file_and_line (DECL_SOURCE_FILE (decl), 1222 DECL_SOURCE_LINE (decl), 1223 "storage size of `%s' isn't known", 1224 IDENTIFIER_POINTER (DECL_NAME (decl))); 1225 TREE_ASM_WRITTEN (decl) = 1; 1226 return; 1227 } 1228 1229 /* The first declaration of a variable that comes through this function 1230 decides whether it is global (in C, has external linkage) 1231 or local (in C, has internal linkage). So do nothing more 1232 if this function has already run. */ 1233 1234 if (TREE_ASM_WRITTEN (decl)) 1235 return; 1236 1237 TREE_ASM_WRITTEN (decl) = 1; 1238 1239 app_disable (); 1240 1241 if (! dont_output_data) 1242 { 1243 int size; 1244 1245 if (TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST) 1246 goto finish; 1247 1248 /* This is better than explicit arithmetic, since it avoids overflow. */ 1249 size_tree = size_binop (CEIL_DIV_EXPR, 1250 DECL_SIZE (decl), size_int (BITS_PER_UNIT)); 1251 1252 size = TREE_INT_CST_LOW (size_tree); 1253 if (TREE_INT_CST_HIGH (size_tree) != 0 1254 || size != TREE_INT_CST_LOW (size_tree)) 1255 { 1256 error_with_decl (decl, "size of variable `%s' is too large"); 1257 goto finish; 1258 } 1259 } 1260 1261 name = XSTR (XEXP (DECL_RTL (decl), 0), 0); 1262 1263 if (TREE_PUBLIC (decl) && DECL_NAME (decl) 1264 && ! first_global_object_name 1265 && ! (DECL_COMMON (decl) && (DECL_INITIAL (decl) == 0 1266 || DECL_INITIAL (decl) == error_mark_node)) 1267 && ! DECL_WEAK (decl) 1268 && ! DECL_ONE_ONLY (decl)) 1269 { 1270 char *p; 1271 1272 STRIP_NAME_ENCODING (p, name); 1273 first_global_object_name = permalloc (strlen (p) + 1); 1274 strcpy (first_global_object_name, p); 1275 } 1276 1277 /* Compute the alignment of this data. */ 1278 1279 align = DECL_ALIGN (decl); 1280 1281 /* In the case for initialing an array whose length isn't specified, 1282 where we have not yet been able to do the layout, 1283 figure out the proper alignment now. */ 1284 if (dont_output_data && DECL_SIZE (decl) == 0 1285 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE) 1286 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl)))); 1287 1288 /* Some object file formats have a maximum alignment which they support. 1289 In particular, a.out format supports a maximum alignment of 4. */ 1290#ifndef MAX_OFILE_ALIGNMENT 1291#define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT 1292#endif 1293 if (align > MAX_OFILE_ALIGNMENT) 1294 { 1295 warning_with_decl (decl, 1296 "alignment of `%s' is greater than maximum object file alignment. Using %d.", 1297 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT); 1298 align = MAX_OFILE_ALIGNMENT; 1299 } 1300 1301 /* On some machines, it is good to increase alignment sometimes. */ 1302#ifdef DATA_ALIGNMENT 1303 align = DATA_ALIGNMENT (TREE_TYPE (decl), align); 1304#endif 1305#ifdef CONSTANT_ALIGNMENT 1306 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node) 1307 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align); 1308#endif 1309 1310 /* Reset the alignment in case we have made it tighter, so we can benefit 1311 from it in get_pointer_alignment. */ 1312 DECL_ALIGN (decl) = align; 1313 1314 /* Handle uninitialized definitions. */ 1315 1316 if ((DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node) 1317 /* If the target can't output uninitialized but not common global data 1318 in .bss, then we have to use .data. */ 1319#if ! defined (ASM_OUTPUT_BSS) && ! defined (ASM_OUTPUT_ALIGNED_BSS) 1320 && DECL_COMMON (decl) 1321#endif 1322 && ! dont_output_data) 1323 { 1324 int size = TREE_INT_CST_LOW (size_tree); 1325 int rounded = size; 1326 1327 /* Don't allocate zero bytes of common, 1328 since that means "undefined external" in the linker. */ 1329 if (size == 0) rounded = 1; 1330 /* Round size up to multiple of BIGGEST_ALIGNMENT bits 1331 so that each uninitialized object starts on such a boundary. */ 1332 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1; 1333 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) 1334 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); 1335 1336#if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS) 1337 if ( (DECL_ALIGN (decl) / BITS_PER_UNIT) > rounded) 1338 warning_with_decl 1339 (decl, "requested alignment for %s is greater than implemented alignment of %d.",rounded); 1340#endif 1341 1342#ifdef DBX_DEBUGGING_INFO 1343 /* File-scope global variables are output here. */ 1344 if (write_symbols == DBX_DEBUG && top_level) 1345 dbxout_symbol (decl, 0); 1346#endif 1347#ifdef SDB_DEBUGGING_INFO 1348 if (write_symbols == SDB_DEBUG && top_level 1349 /* Leave initialized global vars for end of compilation; 1350 see comment in compile_file. */ 1351 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0)) 1352 sdbout_symbol (decl, 0); 1353#endif 1354 1355 /* Don't output any DWARF debugging information for variables here. 1356 In the case of local variables, the information for them is output 1357 when we do our recursive traversal of the tree representation for 1358 the entire containing function. In the case of file-scope variables, 1359 we output information for all of them at the very end of compilation 1360 while we are doing our final traversal of the chain of file-scope 1361 declarations. */ 1362 1363#if 0 /* ??? We should either delete this or add a comment describing what 1364 it was intended to do and why we shouldn't delete it. */ 1365 if (flag_shared_data) 1366 data_section (); 1367#endif 1368 1369 if (TREE_PUBLIC (decl) 1370#if defined (ASM_OUTPUT_BSS) || defined (ASM_OUTPUT_ALIGNED_BSS) 1371 && DECL_COMMON (decl) 1372#endif 1373 ) 1374 { 1375#ifdef ASM_OUTPUT_SHARED_COMMON 1376 if (flag_shared_data) 1377 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded); 1378 else 1379#endif 1380 { 1381#ifdef ASM_OUTPUT_ALIGNED_DECL_COMMON 1382 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, 1383 DECL_ALIGN (decl)); 1384#else 1385#ifdef ASM_OUTPUT_ALIGNED_COMMON 1386 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, 1387 DECL_ALIGN (decl)); 1388#else 1389 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded); 1390#endif 1391#endif 1392 } 1393 } 1394#if defined (ASM_OUTPUT_BSS) || defined (ASM_OUTPUT_ALIGNED_BSS) 1395 else if (TREE_PUBLIC (decl)) 1396 { 1397#ifdef ASM_OUTPUT_SHARED_BSS 1398 if (flag_shared_data) 1399 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded); 1400 else 1401#endif 1402 { 1403#ifdef ASM_OUTPUT_ALIGNED_BSS 1404 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, 1405 DECL_ALIGN (decl)); 1406#else 1407 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded); 1408#endif 1409 } 1410 } 1411#endif /* ASM_OUTPUT_BSS || ASM_OUTPUT_ALIGNED_BSS */ 1412 else 1413 { 1414#ifdef ASM_OUTPUT_SHARED_LOCAL 1415 if (flag_shared_data) 1416 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded); 1417 else 1418#endif 1419 { 1420#ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL 1421 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, 1422 DECL_ALIGN (decl)); 1423#else 1424#ifdef ASM_OUTPUT_ALIGNED_LOCAL 1425 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, 1426 DECL_ALIGN (decl)); 1427#else 1428 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); 1429#endif 1430#endif 1431 } 1432 } 1433 goto finish; 1434 } 1435 1436 /* Handle initialized definitions. 1437 Also handle uninitialized global definitions if -fno-common and the 1438 target doesn't support ASM_OUTPUT_BSS. */ 1439 1440 /* First make the assembler name(s) global if appropriate. */ 1441 if (TREE_PUBLIC (decl) && DECL_NAME (decl)) 1442 { 1443#ifdef ASM_WEAKEN_LABEL 1444 if (DECL_WEAK (decl)) 1445 ASM_WEAKEN_LABEL (asm_out_file, name); 1446 else 1447#endif 1448 ASM_GLOBALIZE_LABEL (asm_out_file, name); 1449 } 1450#if 0 1451 for (d = equivalents; d; d = TREE_CHAIN (d)) 1452 { 1453 tree e = TREE_VALUE (d); 1454 if (TREE_PUBLIC (e) && DECL_NAME (e)) 1455 ASM_GLOBALIZE_LABEL (asm_out_file, 1456 XSTR (XEXP (DECL_RTL (e), 0), 0)); 1457 } 1458#endif 1459 1460 /* Output any data that we will need to use the address of. */ 1461 if (DECL_INITIAL (decl) == error_mark_node) 1462 reloc = contains_pointers_p (TREE_TYPE (decl)); 1463 else if (DECL_INITIAL (decl)) 1464 reloc = output_addressed_constants (DECL_INITIAL (decl)); 1465 1466#ifdef ASM_OUTPUT_SECTION_NAME 1467 if (UNIQUE_SECTION_P (decl)) 1468 UNIQUE_SECTION (decl, reloc); 1469#endif 1470 1471 /* Switch to the appropriate section. */ 1472 variable_section (decl, reloc); 1473 1474 /* dbxout.c needs to know this. */ 1475 if (in_text_section ()) 1476 DECL_IN_TEXT_SECTION (decl) = 1; 1477 1478 /* Record current section so we can restore it if dbxout.c clobbers it. */ 1479 saved_in_section = in_section; 1480 1481 /* Output the dbx info now that we have chosen the section. */ 1482 1483#ifdef DBX_DEBUGGING_INFO 1484 /* File-scope global variables are output here. */ 1485 if (write_symbols == DBX_DEBUG && top_level) 1486 dbxout_symbol (decl, 0); 1487#endif 1488#ifdef SDB_DEBUGGING_INFO 1489 if (write_symbols == SDB_DEBUG && top_level 1490 /* Leave initialized global vars for end of compilation; 1491 see comment in compile_file. */ 1492 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0)) 1493 sdbout_symbol (decl, 0); 1494#endif 1495 1496 /* Don't output any DWARF debugging information for variables here. 1497 In the case of local variables, the information for them is output 1498 when we do our recursive traversal of the tree representation for 1499 the entire containing function. In the case of file-scope variables, 1500 we output information for all of them at the very end of compilation 1501 while we are doing our final traversal of the chain of file-scope 1502 declarations. */ 1503 1504 /* If the debugging output changed sections, reselect the section 1505 that's supposed to be selected. */ 1506 if (in_section != saved_in_section) 1507 variable_section (decl, reloc); 1508 1509 /* Output the alignment of this data. */ 1510 if (align > BITS_PER_UNIT) 1511 ASM_OUTPUT_ALIGN (asm_out_file, 1512 floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT)); 1513 1514 /* Do any machine/system dependent processing of the object. */ 1515#ifdef ASM_DECLARE_OBJECT_NAME 1516 last_assemble_variable_decl = decl; 1517 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl); 1518#else 1519 /* Standard thing is just output label for the object. */ 1520 ASM_OUTPUT_LABEL (asm_out_file, name); 1521#endif /* ASM_DECLARE_OBJECT_NAME */ 1522 1523 if (!dont_output_data) 1524 { 1525 if (DECL_INITIAL (decl)) 1526 /* Output the actual data. */ 1527 output_constant (DECL_INITIAL (decl), TREE_INT_CST_LOW (size_tree)); 1528 else 1529 /* Leave space for it. */ 1530 assemble_zeros (TREE_INT_CST_LOW (size_tree)); 1531 } 1532 1533 finish: 1534#ifdef XCOFF_DEBUGGING_INFO 1535 /* Unfortunately, the IBM assembler cannot handle stabx before the actual 1536 declaration. When something like ".stabx "aa:S-2",aa,133,0" is emitted 1537 and `aa' hasn't been output yet, the assembler generates a stab entry with 1538 a value of zero, in addition to creating an unnecessary external entry 1539 for `aa'. Hence, we must postpone dbxout_symbol to here at the end. */ 1540 1541 /* File-scope global variables are output here. */ 1542 if (write_symbols == XCOFF_DEBUG && top_level) 1543 { 1544 saved_in_section = in_section; 1545 1546 dbxout_symbol (decl, 0); 1547 1548 if (in_section != saved_in_section) 1549 variable_section (decl, reloc); 1550 } 1551#else 1552 /* There must be a statement after a label. */ 1553 ; 1554#endif 1555} 1556 1557/* Return 1 if type TYPE contains any pointers. */ 1558 1559static int 1560contains_pointers_p (type) 1561 tree type; 1562{ 1563 switch (TREE_CODE (type)) 1564 { 1565 case POINTER_TYPE: 1566 case REFERENCE_TYPE: 1567 /* I'm not sure whether OFFSET_TYPE needs this treatment, 1568 so I'll play safe and return 1. */ 1569 case OFFSET_TYPE: 1570 return 1; 1571 1572 case RECORD_TYPE: 1573 case UNION_TYPE: 1574 case QUAL_UNION_TYPE: 1575 { 1576 tree fields; 1577 /* For a type that has fields, see if the fields have pointers. */ 1578 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields)) 1579 if (TREE_CODE (fields) == FIELD_DECL 1580 && contains_pointers_p (TREE_TYPE (fields))) 1581 return 1; 1582 return 0; 1583 } 1584 1585 case ARRAY_TYPE: 1586 /* An array type contains pointers if its element type does. */ 1587 return contains_pointers_p (TREE_TYPE (type)); 1588 1589 default: 1590 return 0; 1591 } 1592} 1593 1594/* Output something to declare an external symbol to the assembler. 1595 (Most assemblers don't need this, so we normally output nothing.) 1596 Do nothing if DECL is not external. */ 1597 1598void 1599assemble_external (decl) 1600 tree decl; 1601{ 1602#ifdef ASM_OUTPUT_EXTERNAL 1603 if (TREE_CODE_CLASS (TREE_CODE (decl)) == 'd' 1604 && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl)) 1605 { 1606 rtx rtl = DECL_RTL (decl); 1607 1608 if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF 1609 && ! SYMBOL_REF_USED (XEXP (rtl, 0))) 1610 { 1611 /* Some systems do require some output. */ 1612 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1; 1613 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0)); 1614 } 1615 } 1616#endif 1617} 1618 1619/* Similar, for calling a library function FUN. */ 1620 1621void 1622assemble_external_libcall (fun) 1623 rtx fun; 1624{ 1625#ifdef ASM_OUTPUT_EXTERNAL_LIBCALL 1626 /* Declare library function name external when first used, if nec. */ 1627 if (! SYMBOL_REF_USED (fun)) 1628 { 1629 SYMBOL_REF_USED (fun) = 1; 1630 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun); 1631 } 1632#endif 1633} 1634 1635/* Declare the label NAME global. */ 1636 1637void 1638assemble_global (name) 1639 char *name; 1640{ 1641 ASM_GLOBALIZE_LABEL (asm_out_file, name); 1642} 1643 1644/* Assemble a label named NAME. */ 1645 1646void 1647assemble_label (name) 1648 char *name; 1649{ 1650 ASM_OUTPUT_LABEL (asm_out_file, name); 1651} 1652 1653/* Output to FILE a reference to the assembler name of a C-level name NAME. 1654 If NAME starts with a *, the rest of NAME is output verbatim. 1655 Otherwise NAME is transformed in an implementation-defined way 1656 (usually by the addition of an underscore). 1657 Many macros in the tm file are defined to call this function. */ 1658 1659void 1660assemble_name (file, name) 1661 FILE *file; 1662 char *name; 1663{ 1664 char *real_name; 1665 tree id; 1666 1667 STRIP_NAME_ENCODING (real_name, name); 1668 if (flag_prefix_function_name 1669 && ! bcmp (real_name, CHKR_PREFIX, CHKR_PREFIX_SIZE)) 1670 real_name = real_name + CHKR_PREFIX_SIZE; 1671 1672 id = maybe_get_identifier (real_name); 1673 if (id) 1674 TREE_SYMBOL_REFERENCED (id) = 1; 1675 1676 if (name[0] == '*') 1677 fputs (&name[1], file); 1678 else 1679 ASM_OUTPUT_LABELREF (file, name); 1680} 1681 1682/* Allocate SIZE bytes writable static space with a gensym name 1683 and return an RTX to refer to its address. */ 1684 1685rtx 1686assemble_static_space (size) 1687 int size; 1688{ 1689 char name[12]; 1690 char *namestring; 1691 rtx x; 1692 1693#if 0 1694 if (flag_shared_data) 1695 data_section (); 1696#endif 1697 1698 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno); 1699 ++const_labelno; 1700 1701 namestring = (char *) obstack_alloc (saveable_obstack, 1702 strlen (name) + 2); 1703 strcpy (namestring, name); 1704 1705 x = gen_rtx_SYMBOL_REF (Pmode, namestring); 1706 1707#ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL 1708 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size, 1709 BIGGEST_ALIGNMENT); 1710#else 1711#ifdef ASM_OUTPUT_ALIGNED_LOCAL 1712 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT); 1713#else 1714 { 1715 /* Round size up to multiple of BIGGEST_ALIGNMENT bits 1716 so that each uninitialized object starts on such a boundary. */ 1717 int rounded = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1) 1718 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) 1719 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); 1720 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); 1721 } 1722#endif 1723#endif 1724 return x; 1725} 1726 1727/* Assemble the static constant template for function entry trampolines. 1728 This is done at most once per compilation. 1729 Returns an RTX for the address of the template. */ 1730 1731#ifdef TRAMPOLINE_TEMPLATE 1732rtx 1733assemble_trampoline_template () 1734{ 1735 char label[256]; 1736 char *name; 1737 int align; 1738 1739 /* By default, put trampoline templates in read-only data section. */ 1740 1741#ifdef TRAMPOLINE_SECTION 1742 TRAMPOLINE_SECTION (); 1743#else 1744 readonly_data_section (); 1745#endif 1746 1747 /* Write the assembler code to define one. */ 1748 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT); 1749 if (align > 0) 1750 ASM_OUTPUT_ALIGN (asm_out_file, align); 1751 1752 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LTRAMP", 0); 1753 TRAMPOLINE_TEMPLATE (asm_out_file); 1754 1755 /* Record the rtl to refer to it. */ 1756 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0); 1757 name 1758 = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label)); 1759 return gen_rtx_SYMBOL_REF (Pmode, name); 1760} 1761#endif 1762 1763/* Assemble the integer constant X into an object of SIZE bytes. 1764 X must be either a CONST_INT or CONST_DOUBLE. 1765 1766 Return 1 if we were able to output the constant, otherwise 0. If FORCE is 1767 non-zero, abort if we can't output the constant. */ 1768 1769int 1770assemble_integer (x, size, force) 1771 rtx x; 1772 int size; 1773 int force; 1774{ 1775 /* First try to use the standard 1, 2, 4, 8, and 16 byte 1776 ASM_OUTPUT... macros. */ 1777 1778 switch (size) 1779 { 1780#ifdef ASM_OUTPUT_CHAR 1781 case 1: 1782 ASM_OUTPUT_CHAR (asm_out_file, x); 1783 return 1; 1784#endif 1785 1786#ifdef ASM_OUTPUT_SHORT 1787 case 2: 1788 ASM_OUTPUT_SHORT (asm_out_file, x); 1789 return 1; 1790#endif 1791 1792#ifdef ASM_OUTPUT_INT 1793 case 4: 1794 ASM_OUTPUT_INT (asm_out_file, x); 1795 return 1; 1796#endif 1797 1798#ifdef ASM_OUTPUT_DOUBLE_INT 1799 case 8: 1800 ASM_OUTPUT_DOUBLE_INT (asm_out_file, x); 1801 return 1; 1802#endif 1803 1804#ifdef ASM_OUTPUT_QUADRUPLE_INT 1805 case 16: 1806 ASM_OUTPUT_QUADRUPLE_INT (asm_out_file, x); 1807 return 1; 1808#endif 1809 } 1810 1811 /* If we couldn't do it that way, there are two other possibilities: First, 1812 if the machine can output an explicit byte and this is a 1 byte constant, 1813 we can use ASM_OUTPUT_BYTE. */ 1814 1815#ifdef ASM_OUTPUT_BYTE 1816 if (size == 1 && GET_CODE (x) == CONST_INT) 1817 { 1818 ASM_OUTPUT_BYTE (asm_out_file, INTVAL (x)); 1819 return 1; 1820 } 1821#endif 1822 1823 /* Finally, if SIZE is larger than a single word, try to output the constant 1824 one word at a time. */ 1825 1826 if (size > UNITS_PER_WORD) 1827 { 1828 int i; 1829 enum machine_mode mode 1830 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0); 1831 rtx word; 1832 1833 for (i = 0; i < size / UNITS_PER_WORD; i++) 1834 { 1835 word = operand_subword (x, i, 0, mode); 1836 1837 if (word == 0) 1838 break; 1839 1840 if (! assemble_integer (word, UNITS_PER_WORD, 0)) 1841 break; 1842 } 1843 1844 if (i == size / UNITS_PER_WORD) 1845 return 1; 1846 /* If we output at least one word and then could not finish, 1847 there is no valid way to continue. */ 1848 if (i > 0) 1849 abort (); 1850 } 1851 1852 if (force) 1853 abort (); 1854 1855 return 0; 1856} 1857 1858/* Assemble the floating-point constant D into an object of size MODE. */ 1859 1860void 1861assemble_real (d, mode) 1862 REAL_VALUE_TYPE d; 1863 enum machine_mode mode; 1864{ 1865 jmp_buf output_constant_handler; 1866 1867 if (setjmp (output_constant_handler)) 1868 { 1869 error ("floating point trap outputting a constant"); 1870#ifdef REAL_IS_NOT_DOUBLE 1871 bzero ((char *) &d, sizeof d); 1872 d = dconst0; 1873#else 1874 d = 0; 1875#endif 1876 } 1877 1878 set_float_handler (output_constant_handler); 1879 1880 switch (mode) 1881 { 1882#ifdef ASM_OUTPUT_BYTE_FLOAT 1883 case QFmode: 1884 ASM_OUTPUT_BYTE_FLOAT (asm_out_file, d); 1885 break; 1886#endif 1887#ifdef ASM_OUTPUT_SHORT_FLOAT 1888 case HFmode: 1889 ASM_OUTPUT_SHORT_FLOAT (asm_out_file, d); 1890 break; 1891#endif 1892#ifdef ASM_OUTPUT_THREE_QUARTER_FLOAT 1893 case TQFmode: 1894 ASM_OUTPUT_THREE_QUARTER_FLOAT (asm_out_file, d); 1895 break; 1896#endif 1897#ifdef ASM_OUTPUT_FLOAT 1898 case SFmode: 1899 ASM_OUTPUT_FLOAT (asm_out_file, d); 1900 break; 1901#endif 1902 1903#ifdef ASM_OUTPUT_DOUBLE 1904 case DFmode: 1905 ASM_OUTPUT_DOUBLE (asm_out_file, d); 1906 break; 1907#endif 1908 1909#ifdef ASM_OUTPUT_LONG_DOUBLE 1910 case XFmode: 1911 case TFmode: 1912 ASM_OUTPUT_LONG_DOUBLE (asm_out_file, d); 1913 break; 1914#endif 1915 1916 default: 1917 abort (); 1918 } 1919 1920 set_float_handler (NULL_PTR); 1921} 1922 1923/* Here we combine duplicate floating constants to make 1924 CONST_DOUBLE rtx's, and force those out to memory when necessary. */ 1925 1926/* Chain of all CONST_DOUBLE rtx's constructed for the current function. 1927 They are chained through the CONST_DOUBLE_CHAIN. 1928 A CONST_DOUBLE rtx has CONST_DOUBLE_MEM != cc0_rtx iff it is on this chain. 1929 In that case, CONST_DOUBLE_MEM is either a MEM, 1930 or const0_rtx if no MEM has been made for this CONST_DOUBLE yet. 1931 1932 (CONST_DOUBLE_MEM is used only for top-level functions. 1933 See force_const_mem for explanation.) */ 1934 1935static rtx const_double_chain; 1936 1937/* Return a CONST_DOUBLE or CONST_INT for a value specified as a pair of ints. 1938 For an integer, I0 is the low-order word and I1 is the high-order word. 1939 For a real number, I0 is the word with the low address 1940 and I1 is the word with the high address. */ 1941 1942rtx 1943immed_double_const (i0, i1, mode) 1944 HOST_WIDE_INT i0, i1; 1945 enum machine_mode mode; 1946{ 1947 register rtx r; 1948 1949 if (GET_MODE_CLASS (mode) == MODE_INT 1950 || GET_MODE_CLASS (mode) == MODE_PARTIAL_INT) 1951 { 1952 /* We clear out all bits that don't belong in MODE, unless they and our 1953 sign bit are all one. So we get either a reasonable negative value 1954 or a reasonable unsigned value for this mode. */ 1955 int width = GET_MODE_BITSIZE (mode); 1956 if (width < HOST_BITS_PER_WIDE_INT 1957 && ((i0 & ((HOST_WIDE_INT) (-1) << (width - 1))) 1958 != ((HOST_WIDE_INT) (-1) << (width - 1)))) 1959 i0 &= ((HOST_WIDE_INT) 1 << width) - 1, i1 = 0; 1960 else if (width == HOST_BITS_PER_WIDE_INT 1961 && ! (i1 == ~0 && i0 < 0)) 1962 i1 = 0; 1963 else if (width > 2 * HOST_BITS_PER_WIDE_INT) 1964 /* We cannot represent this value as a constant. */ 1965 abort (); 1966 1967 /* If this would be an entire word for the target, but is not for 1968 the host, then sign-extend on the host so that the number will look 1969 the same way on the host that it would on the target. 1970 1971 For example, when building a 64 bit alpha hosted 32 bit sparc 1972 targeted compiler, then we want the 32 bit unsigned value -1 to be 1973 represented as a 64 bit value -1, and not as 0x00000000ffffffff. 1974 The later confuses the sparc backend. */ 1975 1976 if (BITS_PER_WORD < HOST_BITS_PER_WIDE_INT && BITS_PER_WORD == width 1977 && (i0 & ((HOST_WIDE_INT) 1 << (width - 1)))) 1978 i0 |= ((HOST_WIDE_INT) (-1) << width); 1979 1980 /* If MODE fits within HOST_BITS_PER_WIDE_INT, always use a CONST_INT. 1981 1982 ??? Strictly speaking, this is wrong if we create a CONST_INT 1983 for a large unsigned constant with the size of MODE being 1984 HOST_BITS_PER_WIDE_INT and later try to interpret that constant in a 1985 wider mode. In that case we will mis-interpret it as a negative 1986 number. 1987 1988 Unfortunately, the only alternative is to make a CONST_DOUBLE 1989 for any constant in any mode if it is an unsigned constant larger 1990 than the maximum signed integer in an int on the host. However, 1991 doing this will break everyone that always expects to see a CONST_INT 1992 for SImode and smaller. 1993 1994 We have always been making CONST_INTs in this case, so nothing new 1995 is being broken. */ 1996 1997 if (width <= HOST_BITS_PER_WIDE_INT) 1998 i1 = (i0 < 0) ? ~(HOST_WIDE_INT) 0 : 0; 1999 2000 /* If this integer fits in one word, return a CONST_INT. */ 2001 if ((i1 == 0 && i0 >= 0) 2002 || (i1 == ~0 && i0 < 0)) 2003 return GEN_INT (i0); 2004 2005 /* We use VOIDmode for integers. */ 2006 mode = VOIDmode; 2007 } 2008 2009 /* Search the chain for an existing CONST_DOUBLE with the right value. 2010 If one is found, return it. */ 2011 2012 for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r)) 2013 if (CONST_DOUBLE_LOW (r) == i0 && CONST_DOUBLE_HIGH (r) == i1 2014 && GET_MODE (r) == mode) 2015 return r; 2016 2017 /* No; make a new one and add it to the chain. 2018 2019 We may be called by an optimizer which may be discarding any memory 2020 allocated during its processing (such as combine and loop). However, 2021 we will be leaving this constant on the chain, so we cannot tolerate 2022 freed memory. So switch to saveable_obstack for this allocation 2023 and then switch back if we were in current_obstack. */ 2024 2025 push_obstacks_nochange (); 2026 rtl_in_saveable_obstack (); 2027 r = gen_rtx_CONST_DOUBLE (mode, NULL_RTX, i0, i1); 2028 pop_obstacks (); 2029 2030 /* Don't touch const_double_chain in nested function; see force_const_mem. 2031 Also, don't touch it if not inside any function. */ 2032 if (outer_function_chain == 0 && current_function_decl != 0) 2033 { 2034 CONST_DOUBLE_CHAIN (r) = const_double_chain; 2035 const_double_chain = r; 2036 } 2037 2038 /* Store const0_rtx in mem-slot since this CONST_DOUBLE is on the chain. 2039 Actual use of mem-slot is only through force_const_mem. */ 2040 2041 CONST_DOUBLE_MEM (r) = const0_rtx; 2042 2043 return r; 2044} 2045 2046/* Return a CONST_DOUBLE for a specified `double' value 2047 and machine mode. */ 2048 2049rtx 2050immed_real_const_1 (d, mode) 2051 REAL_VALUE_TYPE d; 2052 enum machine_mode mode; 2053{ 2054 union real_extract u; 2055 register rtx r; 2056 2057 /* Get the desired `double' value as a sequence of ints 2058 since that is how they are stored in a CONST_DOUBLE. */ 2059 2060 u.d = d; 2061 2062 /* Detect special cases. */ 2063 2064 if (REAL_VALUES_IDENTICAL (dconst0, d)) 2065 return CONST0_RTX (mode); 2066 /* Check for NaN first, because some ports (specifically the i386) do not 2067 emit correct ieee-fp code by default, and thus will generate a core 2068 dump here if we pass a NaN to REAL_VALUES_EQUAL and if REAL_VALUES_EQUAL 2069 does a floating point comparison. */ 2070 else if (! REAL_VALUE_ISNAN (d) && REAL_VALUES_EQUAL (dconst1, d)) 2071 return CONST1_RTX (mode); 2072 2073 if (sizeof u == sizeof (HOST_WIDE_INT)) 2074 return immed_double_const (u.i[0], 0, mode); 2075 if (sizeof u == 2 * sizeof (HOST_WIDE_INT)) 2076 return immed_double_const (u.i[0], u.i[1], mode); 2077 2078 /* The rest of this function handles the case where 2079 a float value requires more than 2 ints of space. 2080 It will be deleted as dead code on machines that don't need it. */ 2081 2082 /* Search the chain for an existing CONST_DOUBLE with the right value. 2083 If one is found, return it. */ 2084 2085 for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r)) 2086 if (! bcmp ((char *) &CONST_DOUBLE_LOW (r), (char *) &u, sizeof u) 2087 && GET_MODE (r) == mode) 2088 return r; 2089 2090 /* No; make a new one and add it to the chain. 2091 2092 We may be called by an optimizer which may be discarding any memory 2093 allocated during its processing (such as combine and loop). However, 2094 we will be leaving this constant on the chain, so we cannot tolerate 2095 freed memory. So switch to saveable_obstack for this allocation 2096 and then switch back if we were in current_obstack. */ 2097 2098 push_obstacks_nochange (); 2099 rtl_in_saveable_obstack (); 2100 r = rtx_alloc (CONST_DOUBLE); 2101 PUT_MODE (r, mode); 2102 bcopy ((char *) &u, (char *) &CONST_DOUBLE_LOW (r), sizeof u); 2103 pop_obstacks (); 2104 2105 /* Don't touch const_double_chain in nested function; see force_const_mem. 2106 Also, don't touch it if not inside any function. */ 2107 if (outer_function_chain == 0 && current_function_decl != 0) 2108 { 2109 CONST_DOUBLE_CHAIN (r) = const_double_chain; 2110 const_double_chain = r; 2111 } 2112 2113 /* Store const0_rtx in CONST_DOUBLE_MEM since this CONST_DOUBLE is on the 2114 chain, but has not been allocated memory. Actual use of CONST_DOUBLE_MEM 2115 is only through force_const_mem. */ 2116 2117 CONST_DOUBLE_MEM (r) = const0_rtx; 2118 2119 return r; 2120} 2121 2122/* Return a CONST_DOUBLE rtx for a value specified by EXP, 2123 which must be a REAL_CST tree node. */ 2124 2125rtx 2126immed_real_const (exp) 2127 tree exp; 2128{ 2129 return immed_real_const_1 (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp))); 2130} 2131 2132/* At the end of a function, forget the memory-constants 2133 previously made for CONST_DOUBLEs. Mark them as not on real_constant_chain. 2134 Also clear out real_constant_chain and clear out all the chain-pointers. */ 2135 2136void 2137clear_const_double_mem () 2138{ 2139 register rtx r, next; 2140 2141 /* Don't touch CONST_DOUBLE_MEM for nested functions. 2142 See force_const_mem for explanation. */ 2143 if (outer_function_chain != 0) 2144 return; 2145 2146 for (r = const_double_chain; r; r = next) 2147 { 2148 next = CONST_DOUBLE_CHAIN (r); 2149 CONST_DOUBLE_CHAIN (r) = 0; 2150 CONST_DOUBLE_MEM (r) = cc0_rtx; 2151 } 2152 const_double_chain = 0; 2153} 2154 2155/* Given an expression EXP with a constant value, 2156 reduce it to the sum of an assembler symbol and an integer. 2157 Store them both in the structure *VALUE. 2158 Abort if EXP does not reduce. */ 2159 2160struct addr_const 2161{ 2162 rtx base; 2163 HOST_WIDE_INT offset; 2164}; 2165 2166static void 2167decode_addr_const (exp, value) 2168 tree exp; 2169 struct addr_const *value; 2170{ 2171 register tree target = TREE_OPERAND (exp, 0); 2172 register int offset = 0; 2173 register rtx x; 2174 2175 while (1) 2176 { 2177 if (TREE_CODE (target) == COMPONENT_REF 2178 && (TREE_CODE (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1))) 2179 == INTEGER_CST)) 2180 { 2181 offset += TREE_INT_CST_LOW (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1))) / BITS_PER_UNIT; 2182 target = TREE_OPERAND (target, 0); 2183 } 2184 else if (TREE_CODE (target) == ARRAY_REF) 2185 { 2186 if (TREE_CODE (TREE_OPERAND (target, 1)) != INTEGER_CST 2187 || TREE_CODE (TYPE_SIZE (TREE_TYPE (target))) != INTEGER_CST) 2188 abort (); 2189 offset += ((TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (target))) 2190 * TREE_INT_CST_LOW (TREE_OPERAND (target, 1))) 2191 / BITS_PER_UNIT); 2192 target = TREE_OPERAND (target, 0); 2193 } 2194 else 2195 break; 2196 } 2197 2198 switch (TREE_CODE (target)) 2199 { 2200 case VAR_DECL: 2201 case FUNCTION_DECL: 2202 x = DECL_RTL (target); 2203 break; 2204 2205 case LABEL_DECL: 2206 x = gen_rtx_MEM (FUNCTION_MODE, 2207 gen_rtx_LABEL_REF (VOIDmode, 2208 label_rtx (TREE_OPERAND (exp, 0)))); 2209 break; 2210 2211 case REAL_CST: 2212 case STRING_CST: 2213 case COMPLEX_CST: 2214 case CONSTRUCTOR: 2215 case INTEGER_CST: 2216 x = TREE_CST_RTL (target); 2217 break; 2218 2219 default: 2220 abort (); 2221 } 2222 2223 if (GET_CODE (x) != MEM) 2224 abort (); 2225 x = XEXP (x, 0); 2226 2227 value->base = x; 2228 value->offset = offset; 2229} 2230 2231/* Uniquize all constants that appear in memory. 2232 Each constant in memory thus far output is recorded 2233 in `const_hash_table' with a `struct constant_descriptor' 2234 that contains a polish representation of the value of 2235 the constant. 2236 2237 We cannot store the trees in the hash table 2238 because the trees may be temporary. */ 2239 2240struct constant_descriptor 2241{ 2242 struct constant_descriptor *next; 2243 char *label; 2244 char contents[1]; 2245}; 2246 2247#define HASHBITS 30 2248#define MAX_HASH_TABLE 1009 2249static struct constant_descriptor *const_hash_table[MAX_HASH_TABLE]; 2250 2251/* Compute a hash code for a constant expression. */ 2252 2253static int 2254const_hash (exp) 2255 tree exp; 2256{ 2257 register char *p; 2258 register int len, hi, i; 2259 register enum tree_code code = TREE_CODE (exp); 2260 2261 /* Either set P and LEN to the address and len of something to hash and 2262 exit the switch or return a value. */ 2263 2264 switch (code) 2265 { 2266 case INTEGER_CST: 2267 p = (char *) &TREE_INT_CST_LOW (exp); 2268 len = 2 * sizeof TREE_INT_CST_LOW (exp); 2269 break; 2270 2271 case REAL_CST: 2272 p = (char *) &TREE_REAL_CST (exp); 2273 len = sizeof TREE_REAL_CST (exp); 2274 break; 2275 2276 case STRING_CST: 2277 p = TREE_STRING_POINTER (exp); 2278 len = TREE_STRING_LENGTH (exp); 2279 break; 2280 2281 case COMPLEX_CST: 2282 return (const_hash (TREE_REALPART (exp)) * 5 2283 + const_hash (TREE_IMAGPART (exp))); 2284 2285 case CONSTRUCTOR: 2286 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2287 { 2288 len = int_size_in_bytes (TREE_TYPE (exp)); 2289 p = (char *) alloca (len); 2290 get_set_constructor_bytes (exp, (unsigned char *) p, len); 2291 break; 2292 } 2293 else 2294 { 2295 register tree link; 2296 2297 /* For record type, include the type in the hashing. 2298 We do not do so for array types 2299 because (1) the sizes of the elements are sufficient 2300 and (2) distinct array types can have the same constructor. 2301 Instead, we include the array size because the constructor could 2302 be shorter. */ 2303 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) 2304 hi = ((unsigned long) TREE_TYPE (exp) & ((1 << HASHBITS) - 1)) 2305 % MAX_HASH_TABLE; 2306 else 2307 hi = ((5 + int_size_in_bytes (TREE_TYPE (exp))) 2308 & ((1 << HASHBITS) - 1)) % MAX_HASH_TABLE; 2309 2310 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2311 if (TREE_VALUE (link)) 2312 hi 2313 = (hi * 603 + const_hash (TREE_VALUE (link))) % MAX_HASH_TABLE; 2314 2315 return hi; 2316 } 2317 2318 case ADDR_EXPR: 2319 { 2320 struct addr_const value; 2321 2322 decode_addr_const (exp, &value); 2323 if (GET_CODE (value.base) == SYMBOL_REF) 2324 { 2325 /* Don't hash the address of the SYMBOL_REF; 2326 only use the offset and the symbol name. */ 2327 hi = value.offset; 2328 p = XSTR (value.base, 0); 2329 for (i = 0; p[i] != 0; i++) 2330 hi = ((hi * 613) + (unsigned) (p[i])); 2331 } 2332 else if (GET_CODE (value.base) == LABEL_REF) 2333 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13; 2334 2335 hi &= (1 << HASHBITS) - 1; 2336 hi %= MAX_HASH_TABLE; 2337 } 2338 return hi; 2339 2340 case PLUS_EXPR: 2341 case MINUS_EXPR: 2342 return (const_hash (TREE_OPERAND (exp, 0)) * 9 2343 + const_hash (TREE_OPERAND (exp, 1))); 2344 2345 case NOP_EXPR: 2346 case CONVERT_EXPR: 2347 case NON_LVALUE_EXPR: 2348 return const_hash (TREE_OPERAND (exp, 0)) * 7 + 2; 2349 2350 default: 2351 abort (); 2352 } 2353 2354 /* Compute hashing function */ 2355 hi = len; 2356 for (i = 0; i < len; i++) 2357 hi = ((hi * 613) + (unsigned) (p[i])); 2358 2359 hi &= (1 << HASHBITS) - 1; 2360 hi %= MAX_HASH_TABLE; 2361 return hi; 2362} 2363 2364/* Compare a constant expression EXP with a constant-descriptor DESC. 2365 Return 1 if DESC describes a constant with the same value as EXP. */ 2366 2367static int 2368compare_constant (exp, desc) 2369 tree exp; 2370 struct constant_descriptor *desc; 2371{ 2372 return 0 != compare_constant_1 (exp, desc->contents); 2373} 2374 2375/* Compare constant expression EXP with a substring P of a constant descriptor. 2376 If they match, return a pointer to the end of the substring matched. 2377 If they do not match, return 0. 2378 2379 Since descriptors are written in polish prefix notation, 2380 this function can be used recursively to test one operand of EXP 2381 against a subdescriptor, and if it succeeds it returns the 2382 address of the subdescriptor for the next operand. */ 2383 2384static char * 2385compare_constant_1 (exp, p) 2386 tree exp; 2387 char *p; 2388{ 2389 register char *strp; 2390 register int len; 2391 register enum tree_code code = TREE_CODE (exp); 2392 2393 if (code != (enum tree_code) *p++) 2394 return 0; 2395 2396 /* Either set STRP, P and LEN to pointers and length to compare and exit the 2397 switch, or return the result of the comparison. */ 2398 2399 switch (code) 2400 { 2401 case INTEGER_CST: 2402 /* Integer constants are the same only if the same width of type. */ 2403 if (*p++ != TYPE_PRECISION (TREE_TYPE (exp))) 2404 return 0; 2405 2406 strp = (char *) &TREE_INT_CST_LOW (exp); 2407 len = 2 * sizeof TREE_INT_CST_LOW (exp); 2408 break; 2409 2410 case REAL_CST: 2411 /* Real constants are the same only if the same width of type. */ 2412 if (*p++ != TYPE_PRECISION (TREE_TYPE (exp))) 2413 return 0; 2414 2415 strp = (char *) &TREE_REAL_CST (exp); 2416 len = sizeof TREE_REAL_CST (exp); 2417 break; 2418 2419 case STRING_CST: 2420 if (flag_writable_strings) 2421 return 0; 2422 2423 if (*p++ != TYPE_MODE (TREE_TYPE (exp))) 2424 return 0; 2425 2426 strp = TREE_STRING_POINTER (exp); 2427 len = TREE_STRING_LENGTH (exp); 2428 if (bcmp ((char *) &TREE_STRING_LENGTH (exp), p, 2429 sizeof TREE_STRING_LENGTH (exp))) 2430 return 0; 2431 2432 p += sizeof TREE_STRING_LENGTH (exp); 2433 break; 2434 2435 case COMPLEX_CST: 2436 p = compare_constant_1 (TREE_REALPART (exp), p); 2437 if (p == 0) 2438 return 0; 2439 2440 return compare_constant_1 (TREE_IMAGPART (exp), p); 2441 2442 case CONSTRUCTOR: 2443 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2444 { 2445 int xlen = len = int_size_in_bytes (TREE_TYPE (exp)); 2446 2447 strp = (char *) alloca (len); 2448 get_set_constructor_bytes (exp, (unsigned char *) strp, len); 2449 if (bcmp ((char *) &xlen, p, sizeof xlen)) 2450 return 0; 2451 2452 p += sizeof xlen; 2453 break; 2454 } 2455 else 2456 { 2457 register tree link; 2458 int length = list_length (CONSTRUCTOR_ELTS (exp)); 2459 tree type; 2460 int have_purpose = 0; 2461 2462 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2463 if (TREE_PURPOSE (link)) 2464 have_purpose = 1; 2465 2466 if (bcmp ((char *) &length, p, sizeof length)) 2467 return 0; 2468 2469 p += sizeof length; 2470 2471 /* For record constructors, insist that the types match. 2472 For arrays, just verify both constructors are for arrays. 2473 Then insist that either both or none have any TREE_PURPOSE 2474 values. */ 2475 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) 2476 type = TREE_TYPE (exp); 2477 else 2478 type = 0; 2479 2480 if (bcmp ((char *) &type, p, sizeof type)) 2481 return 0; 2482 2483 p += sizeof type; 2484 2485 if (bcmp ((char *) &have_purpose, p, sizeof have_purpose)) 2486 return 0; 2487 2488 p += sizeof have_purpose; 2489 2490 /* For arrays, insist that the size in bytes match. */ 2491 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) 2492 { 2493 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (exp)); 2494 2495 if (bcmp ((char *) &size, p, sizeof size)) 2496 return 0; 2497 2498 p += sizeof size; 2499 } 2500 2501 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2502 { 2503 if (TREE_VALUE (link)) 2504 { 2505 if ((p = compare_constant_1 (TREE_VALUE (link), p)) == 0) 2506 return 0; 2507 } 2508 else 2509 { 2510 tree zero = 0; 2511 2512 if (bcmp ((char *) &zero, p, sizeof zero)) 2513 return 0; 2514 2515 p += sizeof zero; 2516 } 2517 2518 if (TREE_PURPOSE (link) 2519 && TREE_CODE (TREE_PURPOSE (link)) == FIELD_DECL) 2520 { 2521 if (bcmp ((char *) &TREE_PURPOSE (link), p, 2522 sizeof TREE_PURPOSE (link))) 2523 return 0; 2524 2525 p += sizeof TREE_PURPOSE (link); 2526 } 2527 else if (TREE_PURPOSE (link)) 2528 { 2529 if ((p = compare_constant_1 (TREE_PURPOSE (link), p)) == 0) 2530 return 0; 2531 } 2532 else if (have_purpose) 2533 { 2534 int zero = 0; 2535 2536 if (bcmp ((char *) &zero, p, sizeof zero)) 2537 return 0; 2538 2539 p += sizeof zero; 2540 } 2541 } 2542 2543 return p; 2544 } 2545 2546 case ADDR_EXPR: 2547 { 2548 struct addr_const value; 2549 2550 decode_addr_const (exp, &value); 2551 strp = (char *) &value.offset; 2552 len = sizeof value.offset; 2553 /* Compare the offset. */ 2554 while (--len >= 0) 2555 if (*p++ != *strp++) 2556 return 0; 2557 2558 /* Compare symbol name. */ 2559 strp = XSTR (value.base, 0); 2560 len = strlen (strp) + 1; 2561 } 2562 break; 2563 2564 case PLUS_EXPR: 2565 case MINUS_EXPR: 2566 p = compare_constant_1 (TREE_OPERAND (exp, 0), p); 2567 if (p == 0) 2568 return 0; 2569 2570 return compare_constant_1 (TREE_OPERAND (exp, 1), p); 2571 2572 case NOP_EXPR: 2573 case CONVERT_EXPR: 2574 case NON_LVALUE_EXPR: 2575 return compare_constant_1 (TREE_OPERAND (exp, 0), p); 2576 2577 default: 2578 abort (); 2579 } 2580 2581 /* Compare constant contents. */ 2582 while (--len >= 0) 2583 if (*p++ != *strp++) 2584 return 0; 2585 2586 return p; 2587} 2588 2589/* Construct a constant descriptor for the expression EXP. 2590 It is up to the caller to enter the descriptor in the hash table. */ 2591 2592static struct constant_descriptor * 2593record_constant (exp) 2594 tree exp; 2595{ 2596 struct constant_descriptor *next = 0; 2597 char *label = 0; 2598 2599 /* Make a struct constant_descriptor. The first two pointers will 2600 be filled in later. Here we just leave space for them. */ 2601 2602 obstack_grow (&permanent_obstack, (char *) &next, sizeof next); 2603 obstack_grow (&permanent_obstack, (char *) &label, sizeof label); 2604 record_constant_1 (exp); 2605 return (struct constant_descriptor *) obstack_finish (&permanent_obstack); 2606} 2607 2608/* Add a description of constant expression EXP 2609 to the object growing in `permanent_obstack'. 2610 No need to return its address; the caller will get that 2611 from the obstack when the object is complete. */ 2612 2613static void 2614record_constant_1 (exp) 2615 tree exp; 2616{ 2617 register char *strp; 2618 register int len; 2619 register enum tree_code code = TREE_CODE (exp); 2620 2621 obstack_1grow (&permanent_obstack, (unsigned int) code); 2622 2623 switch (code) 2624 { 2625 case INTEGER_CST: 2626 obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp))); 2627 strp = (char *) &TREE_INT_CST_LOW (exp); 2628 len = 2 * sizeof TREE_INT_CST_LOW (exp); 2629 break; 2630 2631 case REAL_CST: 2632 obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp))); 2633 strp = (char *) &TREE_REAL_CST (exp); 2634 len = sizeof TREE_REAL_CST (exp); 2635 break; 2636 2637 case STRING_CST: 2638 if (flag_writable_strings) 2639 return; 2640 2641 obstack_1grow (&permanent_obstack, TYPE_MODE (TREE_TYPE (exp))); 2642 strp = TREE_STRING_POINTER (exp); 2643 len = TREE_STRING_LENGTH (exp); 2644 obstack_grow (&permanent_obstack, (char *) &TREE_STRING_LENGTH (exp), 2645 sizeof TREE_STRING_LENGTH (exp)); 2646 break; 2647 2648 case COMPLEX_CST: 2649 record_constant_1 (TREE_REALPART (exp)); 2650 record_constant_1 (TREE_IMAGPART (exp)); 2651 return; 2652 2653 case CONSTRUCTOR: 2654 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2655 { 2656 int nbytes = int_size_in_bytes (TREE_TYPE (exp)); 2657 obstack_grow (&permanent_obstack, &nbytes, sizeof (nbytes)); 2658 obstack_blank (&permanent_obstack, nbytes); 2659 get_set_constructor_bytes 2660 (exp, (unsigned char *) permanent_obstack.next_free-nbytes, 2661 nbytes); 2662 return; 2663 } 2664 else 2665 { 2666 register tree link; 2667 int length = list_length (CONSTRUCTOR_ELTS (exp)); 2668 tree type; 2669 int have_purpose = 0; 2670 2671 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2672 if (TREE_PURPOSE (link)) 2673 have_purpose = 1; 2674 2675 obstack_grow (&permanent_obstack, (char *) &length, sizeof length); 2676 2677 /* For record constructors, insist that the types match. 2678 For arrays, just verify both constructors are for arrays. 2679 Then insist that either both or none have any TREE_PURPOSE 2680 values. */ 2681 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) 2682 type = TREE_TYPE (exp); 2683 else 2684 type = 0; 2685 obstack_grow (&permanent_obstack, (char *) &type, sizeof type); 2686 obstack_grow (&permanent_obstack, (char *) &have_purpose, 2687 sizeof have_purpose); 2688 2689 /* For arrays, insist that the size in bytes match. */ 2690 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) 2691 { 2692 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (exp)); 2693 obstack_grow (&permanent_obstack, (char *) &size, sizeof size); 2694 } 2695 2696 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 2697 { 2698 if (TREE_VALUE (link)) 2699 record_constant_1 (TREE_VALUE (link)); 2700 else 2701 { 2702 tree zero = 0; 2703 2704 obstack_grow (&permanent_obstack, 2705 (char *) &zero, sizeof zero); 2706 } 2707 2708 if (TREE_PURPOSE (link) 2709 && TREE_CODE (TREE_PURPOSE (link)) == FIELD_DECL) 2710 obstack_grow (&permanent_obstack, 2711 (char *) &TREE_PURPOSE (link), 2712 sizeof TREE_PURPOSE (link)); 2713 else if (TREE_PURPOSE (link)) 2714 record_constant_1 (TREE_PURPOSE (link)); 2715 else if (have_purpose) 2716 { 2717 int zero = 0; 2718 2719 obstack_grow (&permanent_obstack, 2720 (char *) &zero, sizeof zero); 2721 } 2722 } 2723 } 2724 return; 2725 2726 case ADDR_EXPR: 2727 { 2728 struct addr_const value; 2729 2730 decode_addr_const (exp, &value); 2731 /* Record the offset. */ 2732 obstack_grow (&permanent_obstack, 2733 (char *) &value.offset, sizeof value.offset); 2734 /* Record the symbol name. */ 2735 obstack_grow (&permanent_obstack, XSTR (value.base, 0), 2736 strlen (XSTR (value.base, 0)) + 1); 2737 } 2738 return; 2739 2740 case PLUS_EXPR: 2741 case MINUS_EXPR: 2742 record_constant_1 (TREE_OPERAND (exp, 0)); 2743 record_constant_1 (TREE_OPERAND (exp, 1)); 2744 return; 2745 2746 case NOP_EXPR: 2747 case CONVERT_EXPR: 2748 case NON_LVALUE_EXPR: 2749 record_constant_1 (TREE_OPERAND (exp, 0)); 2750 return; 2751 2752 default: 2753 abort (); 2754 } 2755 2756 /* Record constant contents. */ 2757 obstack_grow (&permanent_obstack, strp, len); 2758} 2759 2760/* Record a list of constant expressions that were passed to 2761 output_constant_def but that could not be output right away. */ 2762 2763struct deferred_constant 2764{ 2765 struct deferred_constant *next; 2766 tree exp; 2767 int reloc; 2768 int labelno; 2769}; 2770 2771static struct deferred_constant *deferred_constants; 2772 2773/* Another list of constants which should be output after the 2774 function. */ 2775static struct deferred_constant *after_function_constants; 2776 2777/* Nonzero means defer output of addressed subconstants 2778 (i.e., those for which output_constant_def is called.) */ 2779static int defer_addressed_constants_flag; 2780 2781/* Start deferring output of subconstants. */ 2782 2783void 2784defer_addressed_constants () 2785{ 2786 defer_addressed_constants_flag++; 2787} 2788 2789/* Stop deferring output of subconstants, 2790 and output now all those that have been deferred. */ 2791 2792void 2793output_deferred_addressed_constants () 2794{ 2795 struct deferred_constant *p, *next; 2796 2797 defer_addressed_constants_flag--; 2798 2799 if (defer_addressed_constants_flag > 0) 2800 return; 2801 2802 for (p = deferred_constants; p; p = next) 2803 { 2804 output_constant_def_contents (p->exp, p->reloc, p->labelno); 2805 next = p->next; 2806 free (p); 2807 } 2808 2809 deferred_constants = 0; 2810} 2811 2812/* Output any constants which should appear after a function. */ 2813 2814static void 2815output_after_function_constants () 2816{ 2817 struct deferred_constant *p, *next; 2818 2819 for (p = after_function_constants; p; p = next) 2820 { 2821 output_constant_def_contents (p->exp, p->reloc, p->labelno); 2822 next = p->next; 2823 free (p); 2824 } 2825 2826 after_function_constants = 0; 2827} 2828 2829/* Make a copy of the whole tree structure for a constant. 2830 This handles the same types of nodes that compare_constant 2831 and record_constant handle. */ 2832 2833static tree 2834copy_constant (exp) 2835 tree exp; 2836{ 2837 switch (TREE_CODE (exp)) 2838 { 2839 case ADDR_EXPR: 2840 /* For ADDR_EXPR, we do not want to copy the decl whose address 2841 is requested. We do want to copy constants though. */ 2842 if (TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, 0))) == 'c') 2843 return build1 (TREE_CODE (exp), TREE_TYPE (exp), 2844 copy_constant (TREE_OPERAND (exp, 0))); 2845 else 2846 return copy_node (exp); 2847 2848 case INTEGER_CST: 2849 case REAL_CST: 2850 case STRING_CST: 2851 return copy_node (exp); 2852 2853 case COMPLEX_CST: 2854 return build_complex (TREE_TYPE (exp), 2855 copy_constant (TREE_REALPART (exp)), 2856 copy_constant (TREE_IMAGPART (exp))); 2857 2858 case PLUS_EXPR: 2859 case MINUS_EXPR: 2860 return build (TREE_CODE (exp), TREE_TYPE (exp), 2861 copy_constant (TREE_OPERAND (exp, 0)), 2862 copy_constant (TREE_OPERAND (exp, 1))); 2863 2864 case NOP_EXPR: 2865 case CONVERT_EXPR: 2866 case NON_LVALUE_EXPR: 2867 return build1 (TREE_CODE (exp), TREE_TYPE (exp), 2868 copy_constant (TREE_OPERAND (exp, 0))); 2869 2870 case CONSTRUCTOR: 2871 { 2872 tree copy = copy_node (exp); 2873 tree list = copy_list (CONSTRUCTOR_ELTS (exp)); 2874 tree tail; 2875 2876 CONSTRUCTOR_ELTS (copy) = list; 2877 for (tail = list; tail; tail = TREE_CHAIN (tail)) 2878 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail)); 2879 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE) 2880 for (tail = list; tail; tail = TREE_CHAIN (tail)) 2881 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail)); 2882 2883 return copy; 2884 } 2885 2886 default: 2887 abort (); 2888 } 2889} 2890 2891/* Return an rtx representing a reference to constant data in memory 2892 for the constant expression EXP. 2893 2894 If assembler code for such a constant has already been output, 2895 return an rtx to refer to it. 2896 Otherwise, output such a constant in memory (or defer it for later) 2897 and generate an rtx for it. 2898 2899 The TREE_CST_RTL of EXP is set up to point to that rtx. 2900 The const_hash_table records which constants already have label strings. */ 2901 2902rtx 2903output_constant_def (exp) 2904 tree exp; 2905{ 2906 register int hash; 2907 register struct constant_descriptor *desc; 2908 char label[256]; 2909 char *found = 0; 2910 int reloc; 2911 register rtx def; 2912 2913 if (TREE_CST_RTL (exp)) 2914 return TREE_CST_RTL (exp); 2915 2916 /* Make sure any other constants whose addresses appear in EXP 2917 are assigned label numbers. */ 2918 2919 reloc = output_addressed_constants (exp); 2920 2921 /* Compute hash code of EXP. Search the descriptors for that hash code 2922 to see if any of them describes EXP. If yes, the descriptor records 2923 the label number already assigned. */ 2924 2925 hash = const_hash (exp) % MAX_HASH_TABLE; 2926 2927 for (desc = const_hash_table[hash]; desc; desc = desc->next) 2928 if (compare_constant (exp, desc)) 2929 { 2930 found = desc->label; 2931 break; 2932 } 2933 2934 if (found == 0) 2935 { 2936 /* No constant equal to EXP is known to have been output. 2937 Make a constant descriptor to enter EXP in the hash table. 2938 Assign the label number and record it in the descriptor for 2939 future calls to this function to find. */ 2940 2941 /* Create a string containing the label name, in LABEL. */ 2942 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); 2943 2944 desc = record_constant (exp); 2945 desc->next = const_hash_table[hash]; 2946 desc->label 2947 = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label)); 2948 const_hash_table[hash] = desc; 2949 } 2950 else 2951 { 2952 /* Create a string containing the label name, in LABEL. */ 2953 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); 2954 } 2955 2956 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */ 2957 2958 push_obstacks_nochange (); 2959 if (TREE_PERMANENT (exp)) 2960 end_temporary_allocation (); 2961 2962 def = gen_rtx_SYMBOL_REF (Pmode, desc->label); 2963 2964 TREE_CST_RTL (exp) 2965 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), def); 2966 RTX_UNCHANGING_P (TREE_CST_RTL (exp)) = 1; 2967 if (AGGREGATE_TYPE_P (TREE_TYPE (exp))) 2968 MEM_IN_STRUCT_P (TREE_CST_RTL (exp)) = 1; 2969 2970 pop_obstacks (); 2971 2972 /* Optionally set flags or add text to the name to record information 2973 such as that it is a function name. If the name is changed, the macro 2974 ASM_OUTPUT_LABELREF will have to know how to strip this information. */ 2975#ifdef ENCODE_SECTION_INFO 2976 ENCODE_SECTION_INFO (exp); 2977#endif 2978 2979 /* If this is the first time we've seen this particular constant, 2980 output it (or defer its output for later). */ 2981 if (found == 0) 2982 { 2983 int after_function = 0; 2984 2985#ifdef CONSTANT_AFTER_FUNCTION_P 2986 if (current_function_decl != 0 2987 && CONSTANT_AFTER_FUNCTION_P (exp)) 2988 after_function = 1; 2989#endif 2990 2991 if (defer_addressed_constants_flag || after_function) 2992 { 2993 struct deferred_constant *p; 2994 p = (struct deferred_constant *) xmalloc (sizeof (struct deferred_constant)); 2995 2996 push_obstacks_nochange (); 2997 suspend_momentary (); 2998 p->exp = copy_constant (exp); 2999 pop_obstacks (); 3000 p->reloc = reloc; 3001 p->labelno = const_labelno++; 3002 if (after_function) 3003 { 3004 p->next = after_function_constants; 3005 after_function_constants = p; 3006 } 3007 else 3008 { 3009 p->next = deferred_constants; 3010 deferred_constants = p; 3011 } 3012 } 3013 else 3014 output_constant_def_contents (exp, reloc, const_labelno++); 3015 } 3016 3017 return TREE_CST_RTL (exp); 3018} 3019 3020/* Now output assembler code to define the label for EXP, 3021 and follow it with the data of EXP. */ 3022 3023static void 3024output_constant_def_contents (exp, reloc, labelno) 3025 tree exp; 3026 int reloc; 3027 int labelno; 3028{ 3029 int align; 3030 3031 if (IN_NAMED_SECTION (exp)) 3032 named_section (exp, NULL, reloc); 3033 else 3034 { 3035 /* First switch to text section, except for writable strings. */ 3036#ifdef SELECT_SECTION 3037 SELECT_SECTION (exp, reloc); 3038#else 3039 if (((TREE_CODE (exp) == STRING_CST) && flag_writable_strings) 3040 || (flag_pic && reloc)) 3041 data_section (); 3042 else 3043 readonly_data_section (); 3044#endif 3045 } 3046 3047 /* Align the location counter as required by EXP's data type. */ 3048 align = TYPE_ALIGN (TREE_TYPE (exp)); 3049#ifdef CONSTANT_ALIGNMENT 3050 align = CONSTANT_ALIGNMENT (exp, align); 3051#endif 3052 3053 if (align > BITS_PER_UNIT) 3054 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); 3055 3056 /* Output the label itself. */ 3057 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", labelno); 3058 3059 /* Output the value of EXP. */ 3060 output_constant (exp, 3061 (TREE_CODE (exp) == STRING_CST 3062 ? TREE_STRING_LENGTH (exp) 3063 : int_size_in_bytes (TREE_TYPE (exp)))); 3064 3065} 3066 3067/* Similar hash facility for making memory-constants 3068 from constant rtl-expressions. It is used on RISC machines 3069 where immediate integer arguments and constant addresses are restricted 3070 so that such constants must be stored in memory. 3071 3072 This pool of constants is reinitialized for each function 3073 so each function gets its own constants-pool that comes right before it. 3074 3075 All structures allocated here are discarded when functions are saved for 3076 inlining, so they do not need to be allocated permanently. */ 3077 3078#define MAX_RTX_HASH_TABLE 61 3079static struct constant_descriptor **const_rtx_hash_table; 3080 3081/* Structure to represent sufficient information about a constant so that 3082 it can be output when the constant pool is output, so that function 3083 integration can be done, and to simplify handling on machines that reference 3084 constant pool as base+displacement. */ 3085 3086struct pool_constant 3087{ 3088 struct constant_descriptor *desc; 3089 struct pool_constant *next; 3090 enum machine_mode mode; 3091 rtx constant; 3092 int labelno; 3093 int align; 3094 int offset; 3095 int mark; 3096}; 3097 3098/* Pointers to first and last constant in pool. */ 3099 3100static struct pool_constant *first_pool, *last_pool; 3101 3102/* Current offset in constant pool (does not include any machine-specific 3103 header. */ 3104 3105static int pool_offset; 3106 3107/* Structure used to maintain hash table mapping symbols used to their 3108 corresponding constants. */ 3109 3110struct pool_sym 3111{ 3112 char *label; 3113 struct pool_constant *pool; 3114 struct pool_sym *next; 3115}; 3116 3117static struct pool_sym **const_rtx_sym_hash_table; 3118 3119/* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true. 3120 The argument is XSTR (... , 0) */ 3121 3122#define SYMHASH(LABEL) \ 3123 ((((unsigned long) (LABEL)) & ((1 << HASHBITS) - 1)) % MAX_RTX_HASH_TABLE) 3124 3125/* Initialize constant pool hashing for next function. */ 3126 3127void 3128init_const_rtx_hash_table () 3129{ 3130 const_rtx_hash_table 3131 = ((struct constant_descriptor **) 3132 oballoc (MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *))); 3133 const_rtx_sym_hash_table 3134 = ((struct pool_sym **) 3135 oballoc (MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *))); 3136 bzero ((char *) const_rtx_hash_table, 3137 MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *)); 3138 bzero ((char *) const_rtx_sym_hash_table, 3139 MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *)); 3140 3141 first_pool = last_pool = 0; 3142 pool_offset = 0; 3143} 3144 3145/* Save and restore status for a nested function. */ 3146 3147void 3148save_varasm_status (p, context) 3149 struct function *p; 3150 tree context; 3151{ 3152 p->const_rtx_hash_table = const_rtx_hash_table; 3153 p->const_rtx_sym_hash_table = const_rtx_sym_hash_table; 3154 p->first_pool = first_pool; 3155 p->last_pool = last_pool; 3156 p->pool_offset = pool_offset; 3157 p->const_double_chain = const_double_chain; 3158 3159 /* If we are pushing to toplevel, we can't reuse const_double_chain. */ 3160 if (context == NULL_TREE) 3161 const_double_chain = 0; 3162} 3163 3164void 3165restore_varasm_status (p) 3166 struct function *p; 3167{ 3168 const_rtx_hash_table = p->const_rtx_hash_table; 3169 const_rtx_sym_hash_table = p->const_rtx_sym_hash_table; 3170 first_pool = p->first_pool; 3171 last_pool = p->last_pool; 3172 pool_offset = p->pool_offset; 3173 const_double_chain = p->const_double_chain; 3174} 3175 3176enum kind { RTX_DOUBLE, RTX_INT }; 3177 3178struct rtx_const 3179{ 3180#ifdef ONLY_INT_FIELDS 3181 unsigned int kind : 16; 3182 unsigned int mode : 16; 3183#else 3184 enum kind kind : 16; 3185 enum machine_mode mode : 16; 3186#endif 3187 union { 3188 union real_extract du; 3189 struct addr_const addr; 3190 struct {HOST_WIDE_INT high, low;} di; 3191 } un; 3192}; 3193 3194/* Express an rtx for a constant integer (perhaps symbolic) 3195 as the sum of a symbol or label plus an explicit integer. 3196 They are stored into VALUE. */ 3197 3198static void 3199decode_rtx_const (mode, x, value) 3200 enum machine_mode mode; 3201 rtx x; 3202 struct rtx_const *value; 3203{ 3204 /* Clear the whole structure, including any gaps. */ 3205 3206 { 3207 int *p = (int *) value; 3208 int *end = (int *) (value + 1); 3209 while (p < end) 3210 *p++ = 0; 3211 } 3212 3213 value->kind = RTX_INT; /* Most usual kind. */ 3214 value->mode = mode; 3215 3216 switch (GET_CODE (x)) 3217 { 3218 case CONST_DOUBLE: 3219 value->kind = RTX_DOUBLE; 3220 if (GET_MODE (x) != VOIDmode) 3221 { 3222 value->mode = GET_MODE (x); 3223 bcopy ((char *) &CONST_DOUBLE_LOW (x), 3224 (char *) &value->un.du, sizeof value->un.du); 3225 } 3226 else 3227 { 3228 value->un.di.low = CONST_DOUBLE_LOW (x); 3229 value->un.di.high = CONST_DOUBLE_HIGH (x); 3230 } 3231 break; 3232 3233 case CONST_INT: 3234 value->un.addr.offset = INTVAL (x); 3235 break; 3236 3237 case SYMBOL_REF: 3238 case LABEL_REF: 3239 case PC: 3240 value->un.addr.base = x; 3241 break; 3242 3243 case CONST: 3244 x = XEXP (x, 0); 3245 if (GET_CODE (x) == PLUS) 3246 { 3247 value->un.addr.base = XEXP (x, 0); 3248 if (GET_CODE (XEXP (x, 1)) != CONST_INT) 3249 abort (); 3250 value->un.addr.offset = INTVAL (XEXP (x, 1)); 3251 } 3252 else if (GET_CODE (x) == MINUS) 3253 { 3254 value->un.addr.base = XEXP (x, 0); 3255 if (GET_CODE (XEXP (x, 1)) != CONST_INT) 3256 abort (); 3257 value->un.addr.offset = - INTVAL (XEXP (x, 1)); 3258 } 3259 else 3260 abort (); 3261 break; 3262 3263 default: 3264 abort (); 3265 } 3266 3267 if (value->kind == RTX_INT && value->un.addr.base != 0) 3268 switch (GET_CODE (value->un.addr.base)) 3269 { 3270 case SYMBOL_REF: 3271 case LABEL_REF: 3272 /* Use the string's address, not the SYMBOL_REF's address, 3273 for the sake of addresses of library routines. 3274 For a LABEL_REF, compare labels. */ 3275 value->un.addr.base = XEXP (value->un.addr.base, 0); 3276 3277 default: 3278 break; 3279 } 3280} 3281 3282/* Given a MINUS expression, simplify it if both sides 3283 include the same symbol. */ 3284 3285rtx 3286simplify_subtraction (x) 3287 rtx x; 3288{ 3289 struct rtx_const val0, val1; 3290 3291 decode_rtx_const (GET_MODE (x), XEXP (x, 0), &val0); 3292 decode_rtx_const (GET_MODE (x), XEXP (x, 1), &val1); 3293 3294 if (val0.un.addr.base == val1.un.addr.base) 3295 return GEN_INT (val0.un.addr.offset - val1.un.addr.offset); 3296 return x; 3297} 3298 3299/* Compute a hash code for a constant RTL expression. */ 3300 3301static int 3302const_hash_rtx (mode, x) 3303 enum machine_mode mode; 3304 rtx x; 3305{ 3306 register int hi; 3307 register size_t i; 3308 3309 struct rtx_const value; 3310 decode_rtx_const (mode, x, &value); 3311 3312 /* Compute hashing function */ 3313 hi = 0; 3314 for (i = 0; i < sizeof value / sizeof (int); i++) 3315 hi += ((int *) &value)[i]; 3316 3317 hi &= (1 << HASHBITS) - 1; 3318 hi %= MAX_RTX_HASH_TABLE; 3319 return hi; 3320} 3321 3322/* Compare a constant rtl object X with a constant-descriptor DESC. 3323 Return 1 if DESC describes a constant with the same value as X. */ 3324 3325static int 3326compare_constant_rtx (mode, x, desc) 3327 enum machine_mode mode; 3328 rtx x; 3329 struct constant_descriptor *desc; 3330{ 3331 register int *p = (int *) desc->contents; 3332 register int *strp; 3333 register int len; 3334 struct rtx_const value; 3335 3336 decode_rtx_const (mode, x, &value); 3337 strp = (int *) &value; 3338 len = sizeof value / sizeof (int); 3339 3340 /* Compare constant contents. */ 3341 while (--len >= 0) 3342 if (*p++ != *strp++) 3343 return 0; 3344 3345 return 1; 3346} 3347 3348/* Construct a constant descriptor for the rtl-expression X. 3349 It is up to the caller to enter the descriptor in the hash table. */ 3350 3351static struct constant_descriptor * 3352record_constant_rtx (mode, x) 3353 enum machine_mode mode; 3354 rtx x; 3355{ 3356 struct constant_descriptor *ptr; 3357 char *label; 3358 struct rtx_const value; 3359 3360 decode_rtx_const (mode, x, &value); 3361 3362 /* Put these things in the saveable obstack so we can ensure it won't 3363 be freed if we are called from combine or some other phase that discards 3364 memory allocated from function_obstack (current_obstack). */ 3365 obstack_grow (saveable_obstack, &ptr, sizeof ptr); 3366 obstack_grow (saveable_obstack, &label, sizeof label); 3367 3368 /* Record constant contents. */ 3369 obstack_grow (saveable_obstack, &value, sizeof value); 3370 3371 return (struct constant_descriptor *) obstack_finish (saveable_obstack); 3372} 3373 3374/* Given a constant rtx X, make (or find) a memory constant for its value 3375 and return a MEM rtx to refer to it in memory. */ 3376 3377rtx 3378force_const_mem (mode, x) 3379 enum machine_mode mode; 3380 rtx x; 3381{ 3382 register int hash; 3383 register struct constant_descriptor *desc; 3384 char label[256]; 3385 char *found = 0; 3386 rtx def; 3387 3388 /* If we want this CONST_DOUBLE in the same mode as it is in memory 3389 (this will always be true for floating CONST_DOUBLEs that have been 3390 placed in memory, but not for VOIDmode (integer) CONST_DOUBLEs), 3391 use the previous copy. Otherwise, make a new one. Note that in 3392 the unlikely event that this same CONST_DOUBLE is used in two different 3393 modes in an alternating fashion, we will allocate a lot of different 3394 memory locations, but this should be extremely rare. */ 3395 3396 /* Don't use CONST_DOUBLE_MEM in a nested function. 3397 Nested functions have their own constant pools, 3398 so they can't share the same values in CONST_DOUBLE_MEM 3399 with the containing function. */ 3400 if (outer_function_chain == 0) 3401 if (GET_CODE (x) == CONST_DOUBLE 3402 && GET_CODE (CONST_DOUBLE_MEM (x)) == MEM 3403 && GET_MODE (CONST_DOUBLE_MEM (x)) == mode) 3404 return CONST_DOUBLE_MEM (x); 3405 3406 /* Compute hash code of X. Search the descriptors for that hash code 3407 to see if any of them describes X. If yes, the descriptor records 3408 the label number already assigned. */ 3409 3410 hash = const_hash_rtx (mode, x); 3411 3412 for (desc = const_rtx_hash_table[hash]; desc; desc = desc->next) 3413 if (compare_constant_rtx (mode, x, desc)) 3414 { 3415 found = desc->label; 3416 break; 3417 } 3418 3419 if (found == 0) 3420 { 3421 register struct pool_constant *pool; 3422 register struct pool_sym *sym; 3423 int align; 3424 3425 /* No constant equal to X is known to have been output. 3426 Make a constant descriptor to enter X in the hash table. 3427 Assign the label number and record it in the descriptor for 3428 future calls to this function to find. */ 3429 3430 desc = record_constant_rtx (mode, x); 3431 desc->next = const_rtx_hash_table[hash]; 3432 const_rtx_hash_table[hash] = desc; 3433 3434 /* Align the location counter as required by EXP's data type. */ 3435 align = (mode == VOIDmode) ? UNITS_PER_WORD : GET_MODE_SIZE (mode); 3436 if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT) 3437 align = BIGGEST_ALIGNMENT / BITS_PER_UNIT; 3438#ifdef CONSTANT_ALIGNMENT 3439 align = CONSTANT_ALIGNMENT (make_tree (type_for_mode (mode, 0), x), 3440 align * BITS_PER_UNIT) / BITS_PER_UNIT; 3441#endif 3442 3443 pool_offset += align - 1; 3444 pool_offset &= ~ (align - 1); 3445 3446 /* If RTL is not being placed into the saveable obstack, make a 3447 copy of X that is in the saveable obstack in case we are 3448 being called from combine or some other phase that discards 3449 memory it allocates. We used to only do this if it is a 3450 CONST; however, reload can allocate a CONST_INT when 3451 eliminating registers. */ 3452 if (rtl_obstack != saveable_obstack 3453 && (GET_CODE (x) == CONST || GET_CODE (x) == CONST_INT)) 3454 { 3455 push_obstacks_nochange (); 3456 rtl_in_saveable_obstack (); 3457 3458 if (GET_CODE (x) == CONST) 3459 x = gen_rtx_CONST (GET_MODE (x), 3460 gen_rtx_PLUS (GET_MODE (x), 3461 XEXP (XEXP (x, 0), 0), 3462 XEXP (XEXP (x, 0), 1))); 3463 else 3464 x = GEN_INT (INTVAL (x)); 3465 3466 pop_obstacks (); 3467 } 3468 3469 /* Allocate a pool constant descriptor, fill it in, and chain it in. */ 3470 3471 pool = (struct pool_constant *) savealloc (sizeof (struct pool_constant)); 3472 pool->desc = desc; 3473 pool->constant = x; 3474 pool->mode = mode; 3475 pool->labelno = const_labelno; 3476 pool->align = align; 3477 pool->offset = pool_offset; 3478 pool->mark = 1; 3479 pool->next = 0; 3480 3481 if (last_pool == 0) 3482 first_pool = pool; 3483 else 3484 last_pool->next = pool; 3485 3486 last_pool = pool; 3487 pool_offset += GET_MODE_SIZE (mode); 3488 3489 /* Create a string containing the label name, in LABEL. */ 3490 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); 3491 3492 ++const_labelno; 3493 3494 desc->label = found 3495 = (char *) obstack_copy0 (saveable_obstack, label, strlen (label)); 3496 3497 /* Add label to symbol hash table. */ 3498 hash = SYMHASH (found); 3499 sym = (struct pool_sym *) savealloc (sizeof (struct pool_sym)); 3500 sym->label = found; 3501 sym->pool = pool; 3502 sym->next = const_rtx_sym_hash_table[hash]; 3503 const_rtx_sym_hash_table[hash] = sym; 3504 } 3505 3506 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */ 3507 3508 def = gen_rtx_MEM (mode, gen_rtx_SYMBOL_REF (Pmode, found)); 3509 3510 RTX_UNCHANGING_P (def) = 1; 3511 /* Mark the symbol_ref as belonging to this constants pool. */ 3512 CONSTANT_POOL_ADDRESS_P (XEXP (def, 0)) = 1; 3513 current_function_uses_const_pool = 1; 3514 3515 if (outer_function_chain == 0) 3516 if (GET_CODE (x) == CONST_DOUBLE) 3517 { 3518 if (CONST_DOUBLE_MEM (x) == cc0_rtx) 3519 { 3520 CONST_DOUBLE_CHAIN (x) = const_double_chain; 3521 const_double_chain = x; 3522 } 3523 CONST_DOUBLE_MEM (x) = def; 3524 } 3525 3526 return def; 3527} 3528 3529/* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to 3530 the corresponding pool_constant structure. */ 3531 3532static struct pool_constant * 3533find_pool_constant (addr) 3534 rtx addr; 3535{ 3536 struct pool_sym *sym; 3537 char *label = XSTR (addr, 0); 3538 3539 for (sym = const_rtx_sym_hash_table[SYMHASH (label)]; sym; sym = sym->next) 3540 if (sym->label == label) 3541 return sym->pool; 3542 3543 abort (); 3544} 3545 3546/* Given a constant pool SYMBOL_REF, return the corresponding constant. */ 3547 3548rtx 3549get_pool_constant (addr) 3550 rtx addr; 3551{ 3552 return (find_pool_constant (addr))->constant; 3553} 3554 3555/* Similar, return the mode. */ 3556 3557enum machine_mode 3558get_pool_mode (addr) 3559 rtx addr; 3560{ 3561 return (find_pool_constant (addr))->mode; 3562} 3563 3564/* Similar, return the offset in the constant pool. */ 3565 3566int 3567get_pool_offset (addr) 3568 rtx addr; 3569{ 3570 return (find_pool_constant (addr))->offset; 3571} 3572 3573/* Return the size of the constant pool. */ 3574 3575int 3576get_pool_size () 3577{ 3578 return pool_offset; 3579} 3580 3581/* Write all the constants in the constant pool. */ 3582 3583void 3584output_constant_pool (fnname, fndecl) 3585 char *fnname; 3586 tree fndecl; 3587{ 3588 struct pool_constant *pool; 3589 rtx x; 3590 union real_extract u; 3591 3592 /* It is possible for gcc to call force_const_mem and then to later 3593 discard the instructions which refer to the constant. In such a 3594 case we do not need to output the constant. */ 3595 if (optimize >= 0 && flag_expensive_optimizations) 3596 mark_constant_pool (); 3597 3598#ifdef ASM_OUTPUT_POOL_PROLOGUE 3599 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool_offset); 3600#endif 3601 3602 for (pool = first_pool; pool; pool = pool->next) 3603 { 3604 x = pool->constant; 3605 3606 if (! pool->mark) 3607 continue; 3608 3609 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF) 3610 whose CODE_LABEL has been deleted. This can occur if a jump table 3611 is eliminated by optimization. If so, write a constant of zero 3612 instead. Note that this can also happen by turning the 3613 CODE_LABEL into a NOTE. */ 3614 if (((GET_CODE (x) == LABEL_REF 3615 && (INSN_DELETED_P (XEXP (x, 0)) 3616 || GET_CODE (XEXP (x, 0)) == NOTE))) 3617 || (GET_CODE (x) == CONST && GET_CODE (XEXP (x, 0)) == PLUS 3618 && GET_CODE (XEXP (XEXP (x, 0), 0)) == LABEL_REF 3619 && (INSN_DELETED_P (XEXP (XEXP (XEXP (x, 0), 0), 0)) 3620 || GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 0)) == NOTE))) 3621 x = const0_rtx; 3622 3623 /* First switch to correct section. */ 3624#ifdef SELECT_RTX_SECTION 3625 SELECT_RTX_SECTION (pool->mode, x); 3626#else 3627 readonly_data_section (); 3628#endif 3629 3630#ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY 3631 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, pool->mode, 3632 pool->align, pool->labelno, done); 3633#endif 3634 3635 if (pool->align > 1) 3636 ASM_OUTPUT_ALIGN (asm_out_file, exact_log2 (pool->align)); 3637 3638 /* Output the label. */ 3639 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", pool->labelno); 3640 3641 /* Output the value of the constant itself. */ 3642 switch (GET_MODE_CLASS (pool->mode)) 3643 { 3644 case MODE_FLOAT: 3645 if (GET_CODE (x) != CONST_DOUBLE) 3646 abort (); 3647 3648 bcopy ((char *) &CONST_DOUBLE_LOW (x), (char *) &u, sizeof u); 3649 assemble_real (u.d, pool->mode); 3650 break; 3651 3652 case MODE_INT: 3653 case MODE_PARTIAL_INT: 3654 assemble_integer (x, GET_MODE_SIZE (pool->mode), 1); 3655 break; 3656 3657 default: 3658 abort (); 3659 } 3660 3661#ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY 3662 done: ; 3663#endif 3664 3665 } 3666 3667#ifdef ASM_OUTPUT_POOL_EPILOGUE 3668 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool_offset); 3669#endif 3670 3671 /* Done with this pool. */ 3672 first_pool = last_pool = 0; 3673} 3674 3675/* Look through the instructions for this function, and mark all the 3676 entries in the constant pool which are actually being used. */ 3677 3678static void 3679mark_constant_pool () 3680{ 3681 register rtx insn; 3682 struct pool_constant *pool; 3683 3684 if (first_pool == 0) 3685 return; 3686 3687 for (pool = first_pool; pool; pool = pool->next) 3688 pool->mark = 0; 3689 3690 for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) 3691 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i') 3692 mark_constants (PATTERN (insn)); 3693 3694 for (insn = current_function_epilogue_delay_list; 3695 insn; 3696 insn = XEXP (insn, 1)) 3697 if (GET_RTX_CLASS (GET_CODE (insn)) == 'i') 3698 mark_constants (PATTERN (insn)); 3699} 3700 3701static void 3702mark_constants (x) 3703 register rtx x; 3704{ 3705 register int i; 3706 register char *format_ptr; 3707 3708 if (x == 0) 3709 return; 3710 3711 if (GET_CODE (x) == SYMBOL_REF) 3712 { 3713 if (CONSTANT_POOL_ADDRESS_P (x)) 3714 find_pool_constant (x)->mark = 1; 3715 return; 3716 } 3717 /* Never search inside a CONST_DOUBLE, because CONST_DOUBLE_MEM may be 3718 a MEM, but does not constitute a use of that MEM. This is particularly 3719 important inside a nested function, because CONST_DOUBLE_MEM may be 3720 a reference to a MEM in the parent's constant pool. See the comment 3721 in force_const_mem. */ 3722 else if (GET_CODE (x) == CONST_DOUBLE) 3723 return; 3724 3725 /* Insns may appear inside a SEQUENCE. Only check the patterns of 3726 insns, not any notes that may be attached. We don't want to mark 3727 a constant just because it happens to appear in a REG_EQUIV note. */ 3728 if (GET_RTX_CLASS (GET_CODE (x)) == 'i') 3729 { 3730 mark_constants (PATTERN (x)); 3731 return; 3732 } 3733 3734 format_ptr = GET_RTX_FORMAT (GET_CODE (x)); 3735 3736 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (x)); i++) 3737 { 3738 switch (*format_ptr++) 3739 { 3740 case 'e': 3741 mark_constants (XEXP (x, i)); 3742 break; 3743 3744 case 'E': 3745 if (XVEC (x, i) != 0) 3746 { 3747 register int j; 3748 3749 for (j = 0; j < XVECLEN (x, i); j++) 3750 mark_constants (XVECEXP (x, i, j)); 3751 } 3752 break; 3753 3754 case 'S': 3755 case 's': 3756 case '0': 3757 case 'i': 3758 case 'w': 3759 case 'n': 3760 case 'u': 3761 break; 3762 3763 default: 3764 abort (); 3765 } 3766 } 3767} 3768 3769/* Find all the constants whose addresses are referenced inside of EXP, 3770 and make sure assembler code with a label has been output for each one. 3771 Indicate whether an ADDR_EXPR has been encountered. */ 3772 3773static int 3774output_addressed_constants (exp) 3775 tree exp; 3776{ 3777 int reloc = 0; 3778 3779 switch (TREE_CODE (exp)) 3780 { 3781 case ADDR_EXPR: 3782 { 3783 register tree constant = TREE_OPERAND (exp, 0); 3784 3785 while (TREE_CODE (constant) == COMPONENT_REF) 3786 { 3787 constant = TREE_OPERAND (constant, 0); 3788 } 3789 3790 if (TREE_CODE_CLASS (TREE_CODE (constant)) == 'c' 3791 || TREE_CODE (constant) == CONSTRUCTOR) 3792 /* No need to do anything here 3793 for addresses of variables or functions. */ 3794 output_constant_def (constant); 3795 } 3796 reloc = 1; 3797 break; 3798 3799 case PLUS_EXPR: 3800 case MINUS_EXPR: 3801 reloc = output_addressed_constants (TREE_OPERAND (exp, 0)); 3802 reloc |= output_addressed_constants (TREE_OPERAND (exp, 1)); 3803 break; 3804 3805 case NOP_EXPR: 3806 case CONVERT_EXPR: 3807 case NON_LVALUE_EXPR: 3808 reloc = output_addressed_constants (TREE_OPERAND (exp, 0)); 3809 break; 3810 3811 case CONSTRUCTOR: 3812 { 3813 register tree link; 3814 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) 3815 if (TREE_VALUE (link) != 0) 3816 reloc |= output_addressed_constants (TREE_VALUE (link)); 3817 } 3818 break; 3819 3820 default: 3821 break; 3822 } 3823 return reloc; 3824} 3825 3826/* Output assembler code for constant EXP to FILE, with no label. 3827 This includes the pseudo-op such as ".int" or ".byte", and a newline. 3828 Assumes output_addressed_constants has been done on EXP already. 3829 3830 Generate exactly SIZE bytes of assembler data, padding at the end 3831 with zeros if necessary. SIZE must always be specified. 3832 3833 SIZE is important for structure constructors, 3834 since trailing members may have been omitted from the constructor. 3835 It is also important for initialization of arrays from string constants 3836 since the full length of the string constant might not be wanted. 3837 It is also needed for initialization of unions, where the initializer's 3838 type is just one member, and that may not be as long as the union. 3839 3840 There a case in which we would fail to output exactly SIZE bytes: 3841 for a structure constructor that wants to produce more than SIZE bytes. 3842 But such constructors will never be generated for any possible input. */ 3843 3844void 3845output_constant (exp, size) 3846 register tree exp; 3847 register int size; 3848{ 3849 register enum tree_code code = TREE_CODE (TREE_TYPE (exp)); 3850 3851 if (size == 0) 3852 return; 3853 3854 /* Eliminate the NON_LVALUE_EXPR_EXPR that makes a cast not be an lvalue. 3855 That way we get the constant (we hope) inside it. Also, strip off any 3856 NOP_EXPR that converts between two record, union, array, or set types. */ 3857 while ((TREE_CODE (exp) == NOP_EXPR 3858 && (TREE_TYPE (exp) == TREE_TYPE (TREE_OPERAND (exp, 0)) 3859 || AGGREGATE_TYPE_P (TREE_TYPE (exp)))) 3860 || TREE_CODE (exp) == NON_LVALUE_EXPR) 3861 exp = TREE_OPERAND (exp, 0); 3862 3863 /* Allow a constructor with no elements for any data type. 3864 This means to fill the space with zeros. */ 3865 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0) 3866 { 3867 assemble_zeros (size); 3868 return; 3869 } 3870 3871 switch (code) 3872 { 3873 case CHAR_TYPE: 3874 case BOOLEAN_TYPE: 3875 case INTEGER_TYPE: 3876 case ENUMERAL_TYPE: 3877 case POINTER_TYPE: 3878 case REFERENCE_TYPE: 3879 /* ??? What about (int)((float)(int)&foo + 4) */ 3880 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR 3881 || TREE_CODE (exp) == NON_LVALUE_EXPR) 3882 exp = TREE_OPERAND (exp, 0); 3883 3884 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode, 3885 EXPAND_INITIALIZER), 3886 size, 0)) 3887 error ("initializer for integer value is too complicated"); 3888 size = 0; 3889 break; 3890 3891 case REAL_TYPE: 3892 if (TREE_CODE (exp) != REAL_CST) 3893 error ("initializer for floating value is not a floating constant"); 3894 3895 assemble_real (TREE_REAL_CST (exp), 3896 mode_for_size (size * BITS_PER_UNIT, MODE_FLOAT, 0)); 3897 size = 0; 3898 break; 3899 3900 case COMPLEX_TYPE: 3901 output_constant (TREE_REALPART (exp), size / 2); 3902 output_constant (TREE_IMAGPART (exp), size / 2); 3903 size -= (size / 2) * 2; 3904 break; 3905 3906 case ARRAY_TYPE: 3907 if (TREE_CODE (exp) == CONSTRUCTOR) 3908 { 3909 output_constructor (exp, size); 3910 return; 3911 } 3912 else if (TREE_CODE (exp) == STRING_CST) 3913 { 3914 int excess = 0; 3915 3916 if (size > TREE_STRING_LENGTH (exp)) 3917 { 3918 excess = size - TREE_STRING_LENGTH (exp); 3919 size = TREE_STRING_LENGTH (exp); 3920 } 3921 3922 assemble_string (TREE_STRING_POINTER (exp), size); 3923 size = excess; 3924 } 3925 else 3926 abort (); 3927 break; 3928 3929 case RECORD_TYPE: 3930 case UNION_TYPE: 3931 if (TREE_CODE (exp) == CONSTRUCTOR) 3932 output_constructor (exp, size); 3933 else 3934 abort (); 3935 return; 3936 3937 case SET_TYPE: 3938 if (TREE_CODE (exp) == INTEGER_CST) 3939 assemble_integer (expand_expr (exp, NULL_RTX, 3940 VOIDmode, EXPAND_INITIALIZER), 3941 size, 1); 3942 else if (TREE_CODE (exp) == CONSTRUCTOR) 3943 { 3944 unsigned char *buffer = (unsigned char *) alloca (size); 3945 if (get_set_constructor_bytes (exp, buffer, size)) 3946 abort (); 3947 assemble_string ((char *) buffer, size); 3948 } 3949 else 3950 error ("unknown set constructor type"); 3951 return; 3952 3953 default: 3954 break; /* ??? */ 3955 } 3956 3957 if (size > 0) 3958 assemble_zeros (size); 3959} 3960 3961 3962/* Subroutine of output_constant, used for CONSTRUCTORs 3963 (aggregate constants). 3964 Generate at least SIZE bytes, padding if necessary. */ 3965 3966static void 3967output_constructor (exp, size) 3968 tree exp; 3969 int size; 3970{ 3971 register tree link, field = 0; 3972 HOST_WIDE_INT min_index = 0; 3973 /* Number of bytes output or skipped so far. 3974 In other words, current position within the constructor. */ 3975 int total_bytes = 0; 3976 /* Non-zero means BYTE contains part of a byte, to be output. */ 3977 int byte_buffer_in_use = 0; 3978 register int byte; 3979 3980 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT) 3981 abort (); 3982 3983 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) 3984 field = TYPE_FIELDS (TREE_TYPE (exp)); 3985 3986 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE 3987 && TYPE_DOMAIN (TREE_TYPE (exp)) != 0) 3988 min_index 3989 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (exp)))); 3990 3991 /* As LINK goes through the elements of the constant, 3992 FIELD goes through the structure fields, if the constant is a structure. 3993 if the constant is a union, then we override this, 3994 by getting the field from the TREE_LIST element. 3995 But the constant could also be an array. Then FIELD is zero. */ 3996 for (link = CONSTRUCTOR_ELTS (exp); 3997 link; 3998 link = TREE_CHAIN (link), 3999 field = field ? TREE_CHAIN (field) : 0) 4000 { 4001 tree val = TREE_VALUE (link); 4002 tree index = 0; 4003 4004 /* the element in a union constructor specifies the proper field. */ 4005 4006 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE 4007 || TREE_CODE (TREE_TYPE (exp)) == UNION_TYPE) 4008 { 4009 /* if available, use the type given by link */ 4010 if (TREE_PURPOSE (link) != 0) 4011 field = TREE_PURPOSE (link); 4012 } 4013 4014 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) 4015 index = TREE_PURPOSE (link); 4016 4017 /* Eliminate the marker that makes a cast not be an lvalue. */ 4018 if (val != 0) 4019 STRIP_NOPS (val); 4020 4021 if (index && TREE_CODE (index) == RANGE_EXPR) 4022 { 4023 register int fieldsize 4024 = int_size_in_bytes (TREE_TYPE (TREE_TYPE (exp))); 4025 HOST_WIDE_INT lo_index = TREE_INT_CST_LOW (TREE_OPERAND (index, 0)); 4026 HOST_WIDE_INT hi_index = TREE_INT_CST_LOW (TREE_OPERAND (index, 1)); 4027 HOST_WIDE_INT index; 4028 for (index = lo_index; index <= hi_index; index++) 4029 { 4030 /* Output the element's initial value. */ 4031 if (val == 0) 4032 assemble_zeros (fieldsize); 4033 else 4034 output_constant (val, fieldsize); 4035 4036 /* Count its size. */ 4037 total_bytes += fieldsize; 4038 } 4039 } 4040 else if (field == 0 || !DECL_BIT_FIELD (field)) 4041 { 4042 /* An element that is not a bit-field. */ 4043 4044 register int fieldsize; 4045 /* Since this structure is static, 4046 we know the positions are constant. */ 4047 int bitpos = (field ? (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field)) 4048 / BITS_PER_UNIT) 4049 : 0); 4050 if (index != 0) 4051 bitpos = (TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (val))) 4052 / BITS_PER_UNIT 4053 * (TREE_INT_CST_LOW (index) - min_index)); 4054 4055 /* Output any buffered-up bit-fields preceding this element. */ 4056 if (byte_buffer_in_use) 4057 { 4058 ASM_OUTPUT_BYTE (asm_out_file, byte); 4059 total_bytes++; 4060 byte_buffer_in_use = 0; 4061 } 4062 4063 /* Advance to offset of this element. 4064 Note no alignment needed in an array, since that is guaranteed 4065 if each element has the proper size. */ 4066 if ((field != 0 || index != 0) && bitpos != total_bytes) 4067 { 4068 assemble_zeros (bitpos - total_bytes); 4069 total_bytes = bitpos; 4070 } 4071 4072 /* Determine size this element should occupy. */ 4073 if (field) 4074 { 4075 if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST) 4076 abort (); 4077 if (TREE_INT_CST_LOW (DECL_SIZE (field)) > 100000) 4078 { 4079 /* This avoids overflow trouble. */ 4080 tree size_tree = size_binop (CEIL_DIV_EXPR, 4081 DECL_SIZE (field), 4082 size_int (BITS_PER_UNIT)); 4083 fieldsize = TREE_INT_CST_LOW (size_tree); 4084 } 4085 else 4086 { 4087 fieldsize = TREE_INT_CST_LOW (DECL_SIZE (field)); 4088 fieldsize = (fieldsize + BITS_PER_UNIT - 1) / BITS_PER_UNIT; 4089 } 4090 } 4091 else 4092 fieldsize = int_size_in_bytes (TREE_TYPE (TREE_TYPE (exp))); 4093 4094 /* Output the element's initial value. */ 4095 if (val == 0) 4096 assemble_zeros (fieldsize); 4097 else 4098 output_constant (val, fieldsize); 4099 4100 /* Count its size. */ 4101 total_bytes += fieldsize; 4102 } 4103 else if (val != 0 && TREE_CODE (val) != INTEGER_CST) 4104 error ("invalid initial value for member `%s'", 4105 IDENTIFIER_POINTER (DECL_NAME (field))); 4106 else 4107 { 4108 /* Element that is a bit-field. */ 4109 4110 int next_offset = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field)); 4111 int end_offset 4112 = (next_offset + TREE_INT_CST_LOW (DECL_SIZE (field))); 4113 4114 if (val == 0) 4115 val = integer_zero_node; 4116 4117 /* If this field does not start in this (or, next) byte, 4118 skip some bytes. */ 4119 if (next_offset / BITS_PER_UNIT != total_bytes) 4120 { 4121 /* Output remnant of any bit field in previous bytes. */ 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 /* If still not at proper byte, advance to there. */ 4130 if (next_offset / BITS_PER_UNIT != total_bytes) 4131 { 4132 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes); 4133 total_bytes = next_offset / BITS_PER_UNIT; 4134 } 4135 } 4136 4137 if (! byte_buffer_in_use) 4138 byte = 0; 4139 4140 /* We must split the element into pieces that fall within 4141 separate bytes, and combine each byte with previous or 4142 following bit-fields. */ 4143 4144 /* next_offset is the offset n fbits from the beginning of 4145 the structure to the next bit of this element to be processed. 4146 end_offset is the offset of the first bit past the end of 4147 this element. */ 4148 while (next_offset < end_offset) 4149 { 4150 int this_time; 4151 int shift; 4152 HOST_WIDE_INT value; 4153 int next_byte = next_offset / BITS_PER_UNIT; 4154 int next_bit = next_offset % BITS_PER_UNIT; 4155 4156 /* Advance from byte to byte 4157 within this element when necessary. */ 4158 while (next_byte != total_bytes) 4159 { 4160 ASM_OUTPUT_BYTE (asm_out_file, byte); 4161 total_bytes++; 4162 byte = 0; 4163 } 4164 4165 /* Number of bits we can process at once 4166 (all part of the same byte). */ 4167 this_time = MIN (end_offset - next_offset, 4168 BITS_PER_UNIT - next_bit); 4169 if (BYTES_BIG_ENDIAN) 4170 { 4171 /* On big-endian machine, take the most significant bits 4172 first (of the bits that are significant) 4173 and put them into bytes from the most significant end. */ 4174 shift = end_offset - next_offset - this_time; 4175 /* Don't try to take a bunch of bits that cross 4176 the word boundary in the INTEGER_CST. */ 4177 if (shift < HOST_BITS_PER_WIDE_INT 4178 && shift + this_time > HOST_BITS_PER_WIDE_INT) 4179 { 4180 this_time -= (HOST_BITS_PER_WIDE_INT - shift); 4181 shift = HOST_BITS_PER_WIDE_INT; 4182 } 4183 4184 /* Now get the bits from the appropriate constant word. */ 4185 if (shift < HOST_BITS_PER_WIDE_INT) 4186 { 4187 value = TREE_INT_CST_LOW (val); 4188 } 4189 else if (shift < 2 * HOST_BITS_PER_WIDE_INT) 4190 { 4191 value = TREE_INT_CST_HIGH (val); 4192 shift -= HOST_BITS_PER_WIDE_INT; 4193 } 4194 else 4195 abort (); 4196 byte |= (((value >> shift) 4197 & (((HOST_WIDE_INT) 1 << this_time) - 1)) 4198 << (BITS_PER_UNIT - this_time - next_bit)); 4199 } 4200 else 4201 { 4202 /* On little-endian machines, 4203 take first the least significant bits of the value 4204 and pack them starting at the least significant 4205 bits of the bytes. */ 4206 shift = (next_offset 4207 - TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field))); 4208 /* Don't try to take a bunch of bits that cross 4209 the word boundary in the INTEGER_CST. */ 4210 if (shift < HOST_BITS_PER_WIDE_INT 4211 && shift + this_time > HOST_BITS_PER_WIDE_INT) 4212 { 4213 this_time -= (HOST_BITS_PER_WIDE_INT - shift); 4214 shift = HOST_BITS_PER_WIDE_INT; 4215 } 4216 4217 /* Now get the bits from the appropriate constant word. */ 4218 if (shift < HOST_BITS_PER_WIDE_INT) 4219 value = TREE_INT_CST_LOW (val); 4220 else if (shift < 2 * HOST_BITS_PER_WIDE_INT) 4221 { 4222 value = TREE_INT_CST_HIGH (val); 4223 shift -= HOST_BITS_PER_WIDE_INT; 4224 } 4225 else 4226 abort (); 4227 byte |= (((value >> shift) 4228 & (((HOST_WIDE_INT) 1 << this_time) - 1)) 4229 << next_bit); 4230 } 4231 next_offset += this_time; 4232 byte_buffer_in_use = 1; 4233 } 4234 } 4235 } 4236 if (byte_buffer_in_use) 4237 { 4238 ASM_OUTPUT_BYTE (asm_out_file, byte); 4239 total_bytes++; 4240 } 4241 if (total_bytes < size) 4242 assemble_zeros (size - total_bytes); 4243} 4244 4245/* Output asm to handle ``#pragma weak'' */ 4246 4247void 4248handle_pragma_weak (what, name, value) 4249 enum pragma_state what; 4250 char *name, *value; 4251{ 4252#ifdef HANDLE_PRAGMA_WEAK 4253 if (what == ps_name || what == ps_value) 4254 { 4255 struct weak_syms *weak = 4256 (struct weak_syms *)permalloc (sizeof (struct weak_syms)); 4257 weak->next = weak_decls; 4258 weak->name = permalloc (strlen (name) + 1); 4259 strcpy (weak->name, name); 4260 4261 if (what != ps_value) 4262 weak->value = NULL_PTR; 4263 4264 else 4265 { 4266 weak->value = permalloc (strlen (value) + 1); 4267 strcpy (weak->value, value); 4268 } 4269 4270 weak_decls = weak; 4271 } 4272 else if (! (what == ps_done || what == ps_start)) 4273 warning ("malformed `#pragma weak'"); 4274#endif /* HANDLE_PRAGMA_WEAK */ 4275} 4276 4277/* Declare DECL to be a weak symbol. */ 4278 4279void 4280declare_weak (decl) 4281 tree decl; 4282{ 4283 if (! TREE_PUBLIC (decl)) 4284 error_with_decl (decl, "weak declaration of `%s' must be public"); 4285 else if (TREE_ASM_WRITTEN (decl)) 4286 error_with_decl (decl, "weak declaration of `%s' must precede definition"); 4287 else if (SUPPORTS_WEAK) 4288 DECL_WEAK (decl) = 1; 4289 4290#ifdef HANDLE_PRAGMA_WEAK 4291 /* Make sure this function name gets on the weak declaration list. */ 4292 handle_pragma_weak (ps_name, 4293 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)), 4294 NULL); 4295#endif 4296} 4297 4298/* Emit any pending weak declarations. */ 4299 4300void 4301weak_finish () 4302{ 4303#ifdef HANDLE_PRAGMA_WEAK 4304 if (HANDLE_PRAGMA_WEAK) 4305 { 4306 struct weak_syms *t; 4307 for (t = weak_decls; t; t = t->next) 4308 { 4309 ASM_WEAKEN_LABEL (asm_out_file, t->name); 4310 if (t->value) 4311 ASM_OUTPUT_DEF (asm_out_file, t->name, t->value); 4312 } 4313 } 4314#endif 4315} 4316 4317void 4318assemble_alias (decl, target) 4319 tree decl, target; 4320{ 4321 char *name; 4322 4323 make_decl_rtl (decl, (char *) 0, 1); 4324 name = XSTR (XEXP (DECL_RTL (decl), 0), 0); 4325 4326#ifdef ASM_OUTPUT_DEF 4327 /* Make name accessible from other files, if appropriate. */ 4328 4329 if (TREE_PUBLIC (decl)) 4330 { 4331#ifdef ASM_WEAKEN_LABEL 4332 if (DECL_WEAK (decl)) 4333 ASM_WEAKEN_LABEL (asm_out_file, name); 4334 else 4335#endif 4336 ASM_GLOBALIZE_LABEL (asm_out_file, name); 4337 } 4338 4339 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target)); 4340 TREE_ASM_WRITTEN (decl) = 1; 4341#else 4342#ifdef ASM_OUTPUT_WEAK_ALIAS 4343 if (! DECL_WEAK (decl)) 4344 warning ("only weak aliases are supported in this configuration"); 4345 4346 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target)); 4347 TREE_ASM_WRITTEN (decl) = 1; 4348#else 4349 warning ("alias definitions not supported in this configuration; ignored"); 4350#endif 4351#endif 4352} 4353 4354/* This determines whether or not we support link-once semantics. */ 4355#ifndef SUPPORTS_ONE_ONLY 4356#ifdef MAKE_DECL_ONE_ONLY 4357#define SUPPORTS_ONE_ONLY 1 4358#else 4359#define SUPPORTS_ONE_ONLY 0 4360#endif 4361#endif 4362 4363/* Returns 1 if the target configuration supports defining public symbols 4364 so that one of them will be chosen at link time instead of generating a 4365 multiply-defined symbol error, whether through the use of weak symbols or 4366 a target-specific mechanism for having duplicates discarded. */ 4367 4368int 4369supports_one_only () 4370{ 4371 if (SUPPORTS_ONE_ONLY) 4372 return 1; 4373 return SUPPORTS_WEAK; 4374} 4375 4376/* Set up DECL as a public symbol that can be defined in multiple 4377 translation units without generating a linker error. */ 4378 4379void 4380make_decl_one_only (decl) 4381 tree decl; 4382{ 4383 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL) 4384 abort (); 4385 4386 TREE_PUBLIC (decl) = 1; 4387 4388 if (TREE_CODE (decl) == VAR_DECL 4389 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node)) 4390 DECL_COMMON (decl) = 1; 4391 else if (SUPPORTS_ONE_ONLY) 4392 { 4393#ifdef MAKE_DECL_ONE_ONLY 4394 MAKE_DECL_ONE_ONLY (decl); 4395#endif 4396 DECL_ONE_ONLY (decl) = 1; 4397 } 4398 else if (SUPPORTS_WEAK) 4399 DECL_WEAK (decl) = 1; 4400 else 4401 abort (); 4402} 4403