gcc/tree-core.h

   1 /* Core data structures for the 'tree' type.
   2    Copyright (C) 1989-2013 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_TREE_CORE_H
  21 #define GCC_TREE_CORE_H
  22
  23 #include "hashtab.h"
  24 #include "machmode.h"
  25 #include "input.h"
  26 #include "statistics.h"
  27 #include "vec.h"
  28 #include "double-int.h"
  29 #include "real.h"
  30 #include "fixed-value.h"
  31 #include "alias.h"
  32 #include "flags.h"
  33 #include "symtab.h"
  34
  35 /* This file contains all the data structures that define the 'tree' type.
  36    There are no accessor macros nor functions in this file. Only the
  37    basic data structures, extern declarations and type definitions.  */
  38
  39 /*---------------------------------------------------------------------------
  40    Forward type declarations.  Mostly to avoid including unnecessary headers
  41 ---------------------------------------------------------------------------*/
  42 struct function;
  43 struct real_value;
  44 struct fixed_value;
  45 struct ptr_info_def;
  46 struct range_info_def;
  47 struct die_struct;
  48 struct pointer_set_t;
  49
  50
  51 /*---------------------------------------------------------------------------
  52                               #defined constants
  53 ---------------------------------------------------------------------------*/
  54 /* Nonzero if this is a call to a function whose return value depends
  55    solely on its arguments, has no side effects, and does not read
  56    global memory.  This corresponds to TREE_READONLY for function
  57    decls.  */
  58 #define ECF_CONST                 (1 << 0)
  59
  60 /* Nonzero if this is a call to "pure" function (like const function,
  61    but may read memory.  This corresponds to DECL_PURE_P for function
  62    decls.  */
  63 #define ECF_PURE                  (1 << 1)
  64
  65 /* Nonzero if this is ECF_CONST or ECF_PURE but cannot be proven to no
  66    infinite loop.  This corresponds to DECL_LOOPING_CONST_OR_PURE_P
  67    for function decls.*/
  68 #define ECF_LOOPING_CONST_OR_PURE (1 << 2)
  69
  70 /* Nonzero if this call will never return.  */
  71 #define ECF_NORETURN              (1 << 3)
  72
  73 /* Nonzero if this is a call to malloc or a related function.  */
  74 #define ECF_MALLOC                (1 << 4)
  75
  76 /* Nonzero if it is plausible that this is a call to alloca.  */
  77 #define ECF_MAY_BE_ALLOCA         (1 << 5)
  78
  79 /* Nonzero if this is a call to a function that won't throw an exception.  */
  80 #define ECF_NOTHROW               (1 << 6)
  81
  82 /* Nonzero if this is a call to setjmp or a related function.  */
  83 #define ECF_RETURNS_TWICE         (1 << 7)
  84
  85 /* Nonzero if this call replaces the current stack frame.  */
  86 #define ECF_SIBCALL               (1 << 8)
  87
  88 /* Function does not read or write memory (but may have side effects, so
  89    it does not necessarily fit ECF_CONST).  */
  90 #define ECF_NOVOPS                (1 << 9)
  91
  92 /* The function does not lead to calls within current function unit.  */
  93 #define ECF_LEAF                  (1 << 10)
  94
  95 /* Nonzero if this call does not affect transactions.  */
  96 #define ECF_TM_PURE               (1 << 11)
  97
  98 /* Nonzero if this call is into the transaction runtime library.  */
  99 #define ECF_TM_BUILTIN            (1 << 12)
 100
 101 /* Call argument flags.  */
 102 /* Nonzero if the argument is not dereferenced recursively, thus only
 103    directly reachable memory is read or written.  */
 104 #define EAF_DIRECT              (1 << 0)
 105
 106 /* Nonzero if memory reached by the argument is not clobbered.  */
 107 #define EAF_NOCLOBBER           (1 << 1)
 108
 109 /* Nonzero if the argument does not escape.  */
 110 #define EAF_NOESCAPE            (1 << 2)
 111
 112 /* Nonzero if the argument is not used by the function.  */
 113 #define EAF_UNUSED              (1 << 3)
 114
 115 /* Call return flags.  */
 116 /* Mask for the argument number that is returned.  Lower two bits of
 117    the return flags, encodes argument slots zero to three.  */
 118 #define ERF_RETURN_ARG_MASK     (3)
 119
 120 /* Nonzero if the return value is equal to the argument number
 121    flags & ERF_RETURN_ARG_MASK.  */
 122 #define ERF_RETURNS_ARG         (1 << 2)
 123
 124 /* Nonzero if the return value does not alias with anything.  Functions
 125    with the malloc attribute have this set on their return value.  */
 126 #define ERF_NOALIAS             (1 << 3)
 127
 128
 129 /*---------------------------------------------------------------------------
 130                                   Enumerations
 131 ---------------------------------------------------------------------------*/
 132 /* Codes of tree nodes.  */
 133 #define DEFTREECODE(SYM, STRING, TYPE, NARGS)   SYM,
 134 #define END_OF_BASE_TREE_CODES LAST_AND_UNUSED_TREE_CODE,
 135
 136 enum tree_code {
 137 #include "all-tree.def"
 138 MAX_TREE_CODES
 139 };
 140
 141 #undef DEFTREECODE
 142 #undef END_OF_BASE_TREE_CODES
 143
 144 /* Number of language-independent tree codes.  */
 145 #define NUM_TREE_CODES \
 146   ((int) LAST_AND_UNUSED_TREE_CODE)
 147
 148 #define CODE_CONTAINS_STRUCT(CODE, STRUCT) \
 149   (tree_contains_struct[(CODE)][(STRUCT)])
 150
 151
 152 /* Classify which part of the compiler has defined a given builtin function.
 153    Note that we assume below that this is no more than two bits.  */
 154 enum built_in_class {
 155   NOT_BUILT_IN = 0,
 156   BUILT_IN_FRONTEND,
 157   BUILT_IN_MD,
 158   BUILT_IN_NORMAL
 159 };
 160
 161 /* Last marker used for LTO stremaing of built_in_class.  We can not add it
 162    to the enum since we need the enumb to fit in 2 bits.  */
 163 #define BUILT_IN_LAST (BUILT_IN_NORMAL + 1)
 164
 165 /* Codes that identify the various built in functions
 166    so that expand_call can identify them quickly.  */
 167 #define DEF_BUILTIN(ENUM, N, C, T, LT, B, F, NA, AT, IM, COND) ENUM,
 168 enum built_in_function {
 169 #include "builtins.def"
 170
 171   /* Complex division routines in libgcc.  These are done via builtins
 172      because emit_library_call_value can't handle complex values.  */
 173   BUILT_IN_COMPLEX_MUL_MIN,
 174   BUILT_IN_COMPLEX_MUL_MAX
 175     = BUILT_IN_COMPLEX_MUL_MIN
 176       + MAX_MODE_COMPLEX_FLOAT
 177       - MIN_MODE_COMPLEX_FLOAT,
 178
 179   BUILT_IN_COMPLEX_DIV_MIN,
 180   BUILT_IN_COMPLEX_DIV_MAX
 181     = BUILT_IN_COMPLEX_DIV_MIN
 182       + MAX_MODE_COMPLEX_FLOAT
 183       - MIN_MODE_COMPLEX_FLOAT,
 184
 185   /* Upper bound on non-language-specific builtins.  */
 186   END_BUILTINS
 187 };
 188 #undef DEF_BUILTIN
 189
 190 /* Tree code classes.  Each tree_code has an associated code class
 191    represented by a TREE_CODE_CLASS.  */
 192 enum tree_code_class {
 193   tcc_exceptional, /* An exceptional code (fits no category).  */
 194   tcc_constant,    /* A constant.  */
 195   /* Order of tcc_type and tcc_declaration is important.  */
 196   tcc_type,        /* A type object code.  */
 197   tcc_declaration, /* A declaration (also serving as variable refs).  */
 198   tcc_reference,   /* A reference to storage.  */
 199   tcc_comparison,  /* A comparison expression.  */
 200   tcc_unary,       /* A unary arithmetic expression.  */
 201   tcc_binary,      /* A binary arithmetic expression.  */
 202   tcc_statement,   /* A statement expression, which have side effects
 203                       but usually no interesting value.  */
 204   tcc_vl_exp,      /* A function call or other expression with a
 205                       variable-length operand vector.  */
 206   tcc_expression   /* Any other expression.  */
 207 };
 208
 209 /* OMP_CLAUSE codes.  Do not reorder, as this is used to index into
 210    the tables omp_clause_num_ops and omp_clause_code_name.  */
 211 enum omp_clause_code {
 212   /* Clause zero is special-cased inside the parser
 213      (c_parser_omp_variable_list).  */
 214   OMP_CLAUSE_ERROR = 0,
 215
 216   /* OpenMP clause: private (variable_list).  */
 217   OMP_CLAUSE_PRIVATE,
 218
 219   /* OpenMP clause: shared (variable_list).  */
 220   OMP_CLAUSE_SHARED,
 221
 222   /* OpenMP clause: firstprivate (variable_list).  */
 223   OMP_CLAUSE_FIRSTPRIVATE,
 224
 225   /* OpenMP clause: lastprivate (variable_list).  */
 226   OMP_CLAUSE_LASTPRIVATE,
 227
 228   /* OpenMP clause: reduction (operator:variable_list).
 229      OMP_CLAUSE_REDUCTION_CODE: The tree_code of the operator.
 230      Operand 1: OMP_CLAUSE_REDUCTION_INIT: Stmt-list to initialize the var.
 231      Operand 2: OMP_CLAUSE_REDUCTION_MERGE: Stmt-list to merge private var
 232                 into the shared one.
 233      Operand 3: OMP_CLAUSE_REDUCTION_PLACEHOLDER: A dummy VAR_DECL
 234                 placeholder used in OMP_CLAUSE_REDUCTION_{INIT,MERGE}.  */
 235   OMP_CLAUSE_REDUCTION,
 236
 237   /* OpenMP clause: copyin (variable_list).  */
 238   OMP_CLAUSE_COPYIN,
 239
 240   /* OpenMP clause: copyprivate (variable_list).  */
 241   OMP_CLAUSE_COPYPRIVATE,
 242
 243   /* OpenMP clause: linear (variable-list[:linear-step]).  */
 244   OMP_CLAUSE_LINEAR,
 245
 246   /* OpenMP clause: aligned (variable-list[:alignment]).  */
 247   OMP_CLAUSE_ALIGNED,
 248
 249   /* OpenMP clause: depend ({in,out,inout}:variable-list).  */
 250   OMP_CLAUSE_DEPEND,
 251
 252   /* OpenMP clause: uniform (argument-list).  */
 253   OMP_CLAUSE_UNIFORM,
 254
 255   /* OpenMP clause: from (variable-list).  */
 256   OMP_CLAUSE_FROM,
 257
 258   /* OpenMP clause: to (variable-list).  */
 259   OMP_CLAUSE_TO,
 260
 261   /* OpenMP clause: map ({alloc:,to:,from:,tofrom:,}variable-list).  */
 262   OMP_CLAUSE_MAP,
 263
 264   /* Internal clause: temporary for combined loops expansion.  */
 265   OMP_CLAUSE__LOOPTEMP_,
 266
 267   /* OpenMP clause: if (scalar-expression).  */
 268   OMP_CLAUSE_IF,
 269
 270   /* OpenMP clause: num_threads (integer-expression).  */
 271   OMP_CLAUSE_NUM_THREADS,
 272
 273   /* OpenMP clause: schedule.  */
 274   OMP_CLAUSE_SCHEDULE,
 275
 276   /* OpenMP clause: nowait.  */
 277   OMP_CLAUSE_NOWAIT,
 278
 279   /* OpenMP clause: ordered.  */
 280   OMP_CLAUSE_ORDERED,
 281
 282   /* OpenMP clause: default.  */
 283   OMP_CLAUSE_DEFAULT,
 284
 285   /* OpenMP clause: collapse (constant-integer-expression).  */
 286   OMP_CLAUSE_COLLAPSE,
 287
 288   /* OpenMP clause: untied.  */
 289   OMP_CLAUSE_UNTIED,
 290
 291   /* OpenMP clause: final (scalar-expression).  */
 292   OMP_CLAUSE_FINAL,
 293
 294   /* OpenMP clause: mergeable.  */
 295   OMP_CLAUSE_MERGEABLE,
 296
 297   /* OpenMP clause: device (integer-expression).  */
 298   OMP_CLAUSE_DEVICE,
 299
 300   /* OpenMP clause: dist_schedule (static[:chunk-size]).  */
 301   OMP_CLAUSE_DIST_SCHEDULE,
 302
 303   /* OpenMP clause: inbranch.  */
 304   OMP_CLAUSE_INBRANCH,
 305
 306   /* OpenMP clause: notinbranch.  */
 307   OMP_CLAUSE_NOTINBRANCH,
 308
 309   /* OpenMP clause: num_teams(integer-expression).  */
 310   OMP_CLAUSE_NUM_TEAMS,
 311
 312   /* OpenMP clause: thread_limit(integer-expression).  */
 313   OMP_CLAUSE_THREAD_LIMIT,
 314
 315   /* OpenMP clause: proc_bind ({master,close,spread}).  */
 316   OMP_CLAUSE_PROC_BIND,
 317
 318   /* OpenMP clause: safelen (constant-integer-expression).  */
 319   OMP_CLAUSE_SAFELEN,
 320
 321   /* OpenMP clause: simdlen (constant-integer-expression).  */
 322   OMP_CLAUSE_SIMDLEN,
 323
 324   /* OpenMP clause: for.  */
 325   OMP_CLAUSE_FOR,
 326
 327   /* OpenMP clause: parallel.  */
 328   OMP_CLAUSE_PARALLEL,
 329
 330   /* OpenMP clause: sections.  */
 331   OMP_CLAUSE_SECTIONS,
 332
 333   /* OpenMP clause: taskgroup.  */
 334   OMP_CLAUSE_TASKGROUP,
 335
 336   /* Internally used only clause, holding SIMD uid.  */
 337   OMP_CLAUSE__SIMDUID_
 338 };
 339
 340 #undef DEFTREESTRUCT
 341 #define DEFTREESTRUCT(ENUM, NAME) ENUM,
 342 enum tree_node_structure_enum {
 343 #include "treestruct.def"
 344   LAST_TS_ENUM
 345 };
 346 #undef DEFTREESTRUCT
 347
 348 enum omp_clause_schedule_kind {
 349   OMP_CLAUSE_SCHEDULE_STATIC,
 350   OMP_CLAUSE_SCHEDULE_DYNAMIC,
 351   OMP_CLAUSE_SCHEDULE_GUIDED,
 352   OMP_CLAUSE_SCHEDULE_AUTO,
 353   OMP_CLAUSE_SCHEDULE_RUNTIME
 354 };
 355
 356 enum omp_clause_default_kind {
 357   OMP_CLAUSE_DEFAULT_UNSPECIFIED,
 358   OMP_CLAUSE_DEFAULT_SHARED,
 359   OMP_CLAUSE_DEFAULT_NONE,
 360   OMP_CLAUSE_DEFAULT_PRIVATE,
 361   OMP_CLAUSE_DEFAULT_FIRSTPRIVATE
 362 };
 363
 364 /* There is a TYPE_QUAL value for each type qualifier.  They can be
 365    combined by bitwise-or to form the complete set of qualifiers for a
 366    type.  */
 367 enum cv_qualifier {
 368   TYPE_UNQUALIFIED   = 0x0,
 369   TYPE_QUAL_CONST    = 0x1,
 370   TYPE_QUAL_VOLATILE = 0x2,
 371   TYPE_QUAL_RESTRICT = 0x4
 372 };
 373
 374 /* Enumerate visibility settings.  */
 375 #ifndef SYMBOL_VISIBILITY_DEFINED
 376 #define SYMBOL_VISIBILITY_DEFINED
 377 enum symbol_visibility {
 378   VISIBILITY_DEFAULT,
 379   VISIBILITY_PROTECTED,
 380   VISIBILITY_HIDDEN,
 381   VISIBILITY_INTERNAL
 382 };
 383 #endif  // SYMBOL_VISIBILITY_DEFINED
 384
 385 /* Standard named or nameless data types of the C compiler.  */
 386 enum tree_index {
 387   TI_ERROR_MARK,
 388   TI_INTQI_TYPE,
 389   TI_INTHI_TYPE,
 390   TI_INTSI_TYPE,
 391   TI_INTDI_TYPE,
 392   TI_INTTI_TYPE,
 393
 394   TI_UINTQI_TYPE,
 395   TI_UINTHI_TYPE,
 396   TI_UINTSI_TYPE,
 397   TI_UINTDI_TYPE,
 398   TI_UINTTI_TYPE,
 399
 400   TI_UINT16_TYPE,
 401   TI_UINT32_TYPE,
 402   TI_UINT64_TYPE,
 403
 404   TI_INTEGER_ZERO,
 405   TI_INTEGER_ONE,
 406   TI_INTEGER_THREE,
 407   TI_INTEGER_MINUS_ONE,
 408   TI_NULL_POINTER,
 409
 410   TI_SIZE_ZERO,
 411   TI_SIZE_ONE,
 412
 413   TI_BITSIZE_ZERO,
 414   TI_BITSIZE_ONE,
 415   TI_BITSIZE_UNIT,
 416
 417   TI_PUBLIC,
 418   TI_PROTECTED,
 419   TI_PRIVATE,
 420
 421   TI_BOOLEAN_FALSE,
 422   TI_BOOLEAN_TRUE,
 423
 424   TI_COMPLEX_INTEGER_TYPE,
 425   TI_COMPLEX_FLOAT_TYPE,
 426   TI_COMPLEX_DOUBLE_TYPE,
 427   TI_COMPLEX_LONG_DOUBLE_TYPE,
 428
 429   TI_FLOAT_TYPE,
 430   TI_DOUBLE_TYPE,
 431   TI_LONG_DOUBLE_TYPE,
 432
 433   TI_FLOAT_PTR_TYPE,
 434   TI_DOUBLE_PTR_TYPE,
 435   TI_LONG_DOUBLE_PTR_TYPE,
 436   TI_INTEGER_PTR_TYPE,
 437
 438   TI_VOID_TYPE,
 439   TI_PTR_TYPE,
 440   TI_CONST_PTR_TYPE,
 441   TI_SIZE_TYPE,
 442   TI_PID_TYPE,
 443   TI_PTRDIFF_TYPE,
 444   TI_VA_LIST_TYPE,
 445   TI_VA_LIST_GPR_COUNTER_FIELD,
 446   TI_VA_LIST_FPR_COUNTER_FIELD,
 447   TI_BOOLEAN_TYPE,
 448   TI_FILEPTR_TYPE,
 449   TI_POINTER_SIZED_TYPE,
 450
 451   TI_POINTER_BOUNDS_TYPE,
 452
 453   TI_DFLOAT32_TYPE,
 454   TI_DFLOAT64_TYPE,
 455   TI_DFLOAT128_TYPE,
 456   TI_DFLOAT32_PTR_TYPE,
 457   TI_DFLOAT64_PTR_TYPE,
 458   TI_DFLOAT128_PTR_TYPE,
 459
 460   TI_VOID_LIST_NODE,
 461
 462   TI_MAIN_IDENTIFIER,
 463
 464   TI_SAT_SFRACT_TYPE,
 465   TI_SAT_FRACT_TYPE,
 466   TI_SAT_LFRACT_TYPE,
 467   TI_SAT_LLFRACT_TYPE,
 468   TI_SAT_USFRACT_TYPE,
 469   TI_SAT_UFRACT_TYPE,
 470   TI_SAT_ULFRACT_TYPE,
 471   TI_SAT_ULLFRACT_TYPE,
 472   TI_SFRACT_TYPE,
 473   TI_FRACT_TYPE,
 474   TI_LFRACT_TYPE,
 475   TI_LLFRACT_TYPE,
 476   TI_USFRACT_TYPE,
 477   TI_UFRACT_TYPE,
 478   TI_ULFRACT_TYPE,
 479   TI_ULLFRACT_TYPE,
 480   TI_SAT_SACCUM_TYPE,
 481   TI_SAT_ACCUM_TYPE,
 482   TI_SAT_LACCUM_TYPE,
 483   TI_SAT_LLACCUM_TYPE,
 484   TI_SAT_USACCUM_TYPE,
 485   TI_SAT_UACCUM_TYPE,
 486   TI_SAT_ULACCUM_TYPE,
 487   TI_SAT_ULLACCUM_TYPE,
 488   TI_SACCUM_TYPE,
 489   TI_ACCUM_TYPE,
 490   TI_LACCUM_TYPE,
 491   TI_LLACCUM_TYPE,
 492   TI_USACCUM_TYPE,
 493   TI_UACCUM_TYPE,
 494   TI_ULACCUM_TYPE,
 495   TI_ULLACCUM_TYPE,
 496   TI_QQ_TYPE,
 497   TI_HQ_TYPE,
 498   TI_SQ_TYPE,
 499   TI_DQ_TYPE,
 500   TI_TQ_TYPE,
 501   TI_UQQ_TYPE,
 502   TI_UHQ_TYPE,
 503   TI_USQ_TYPE,
 504   TI_UDQ_TYPE,
 505   TI_UTQ_TYPE,
 506   TI_SAT_QQ_TYPE,
 507   TI_SAT_HQ_TYPE,
 508   TI_SAT_SQ_TYPE,
 509   TI_SAT_DQ_TYPE,
 510   TI_SAT_TQ_TYPE,
 511   TI_SAT_UQQ_TYPE,
 512   TI_SAT_UHQ_TYPE,
 513   TI_SAT_USQ_TYPE,
 514   TI_SAT_UDQ_TYPE,
 515   TI_SAT_UTQ_TYPE,
 516   TI_HA_TYPE,
 517   TI_SA_TYPE,
 518   TI_DA_TYPE,
 519   TI_TA_TYPE,
 520   TI_UHA_TYPE,
 521   TI_USA_TYPE,
 522   TI_UDA_TYPE,
 523   TI_UTA_TYPE,
 524   TI_SAT_HA_TYPE,
 525   TI_SAT_SA_TYPE,
 526   TI_SAT_DA_TYPE,
 527   TI_SAT_TA_TYPE,
 528   TI_SAT_UHA_TYPE,
 529   TI_SAT_USA_TYPE,
 530   TI_SAT_UDA_TYPE,
 531   TI_SAT_UTA_TYPE,
 532
 533   TI_OPTIMIZATION_DEFAULT,
 534   TI_OPTIMIZATION_CURRENT,
 535   TI_TARGET_OPTION_DEFAULT,
 536   TI_TARGET_OPTION_CURRENT,
 537   TI_CURRENT_TARGET_PRAGMA,
 538   TI_CURRENT_OPTIMIZE_PRAGMA,
 539
 540   TI_MAX
 541 };
 542
 543 /* An enumeration of the standard C integer types.  These must be
 544    ordered so that shorter types appear before longer ones, and so
 545    that signed types appear before unsigned ones, for the correct
 546    functioning of interpret_integer() in c-lex.c.  */
 547 enum integer_type_kind {
 548   itk_char,
 549   itk_signed_char,
 550   itk_unsigned_char,
 551   itk_short,
 552   itk_unsigned_short,
 553   itk_int,
 554   itk_unsigned_int,
 555   itk_long,
 556   itk_unsigned_long,
 557   itk_long_long,
 558   itk_unsigned_long_long,
 559   itk_int128,
 560   itk_unsigned_int128,
 561   itk_none
 562 };
 563
 564 /* A pointer-to-function member type looks like:
 565
 566      struct {
 567        __P __pfn;
 568        ptrdiff_t __delta;
 569      };
 570
 571    If __pfn is NULL, it is a NULL pointer-to-member-function.
 572
 573    (Because the vtable is always the first thing in the object, we
 574    don't need its offset.)  If the function is virtual, then PFN is
 575    one plus twice the index into the vtable; otherwise, it is just a
 576    pointer to the function.
 577
 578    Unfortunately, using the lowest bit of PFN doesn't work in
 579    architectures that don't impose alignment requirements on function
 580    addresses, or that use the lowest bit to tell one ISA from another,
 581    for example.  For such architectures, we use the lowest bit of
 582    DELTA instead of the lowest bit of the PFN, and DELTA will be
 583    multiplied by 2.  */
 584 enum ptrmemfunc_vbit_where_t {
 585   ptrmemfunc_vbit_in_pfn,
 586   ptrmemfunc_vbit_in_delta
 587 };
 588
 589 /* Flags that may be passed in the third argument of decl_attributes, and
 590    to handler functions for attributes.  */
 591 enum attribute_flags {
 592   /* The type passed in is the type of a DECL, and any attributes that
 593      should be passed in again to be applied to the DECL rather than the
 594      type should be returned.  */
 595   ATTR_FLAG_DECL_NEXT = 1,
 596   /* The type passed in is a function return type, and any attributes that
 597      should be passed in again to be applied to the function type rather
 598      than the return type should be returned.  */
 599   ATTR_FLAG_FUNCTION_NEXT = 2,
 600   /* The type passed in is an array element type, and any attributes that
 601      should be passed in again to be applied to the array type rather
 602      than the element type should be returned.  */
 603   ATTR_FLAG_ARRAY_NEXT = 4,
 604   /* The type passed in is a structure, union or enumeration type being
 605      created, and should be modified in place.  */
 606   ATTR_FLAG_TYPE_IN_PLACE = 8,
 607   /* The attributes are being applied by default to a library function whose
 608      name indicates known behavior, and should be silently ignored if they
 609      are not in fact compatible with the function type.  */
 610   ATTR_FLAG_BUILT_IN = 16,
 611   /* A given attribute has been parsed as a C++-11 attribute.  */
 612   ATTR_FLAG_CXX11 = 32
 613 };
 614
 615 /* Types used to represent sizes.  */
 616 enum size_type_kind {
 617   stk_sizetype,         /* Normal representation of sizes in bytes.  */
 618   stk_ssizetype,        /* Signed representation of sizes in bytes.  */
 619   stk_bitsizetype,      /* Normal representation of sizes in bits.  */
 620   stk_sbitsizetype,     /* Signed representation of sizes in bits.  */
 621   stk_type_kind_last
 622 };
 623
 624 enum operand_equal_flag {
 625   OEP_ONLY_CONST = 1,
 626   OEP_PURE_SAME = 2,
 627   OEP_CONSTANT_ADDRESS_OF = 4
 628 };
 629
 630 /* Enum and arrays used for tree allocation stats.
 631    Keep in sync with tree.c:tree_node_kind_names.  */
 632 enum tree_node_kind {
 633   d_kind,
 634   t_kind,
 635   b_kind,
 636   s_kind,
 637   r_kind,
 638   e_kind,
 639   c_kind,
 640   id_kind,
 641   vec_kind,
 642   binfo_kind,
 643   ssa_name_kind,
 644   constr_kind,
 645   x_kind,
 646   lang_decl,
 647   lang_type,
 648   omp_clause_kind,
 649   all_kinds
 650 };
 651
 652 enum annot_expr_kind {
 653   annot_expr_ivdep_kind
 654 };
 655
 656
 657 /*---------------------------------------------------------------------------
 658                                 Type definitions
 659 ---------------------------------------------------------------------------*/
 660 /* When processing aliases at the symbol table level, we need the
 661    declaration of target. For this reason we need to queue aliases and
 662    process them after all declarations has been produced.  */
 663 typedef struct GTY(()) alias_pair {
 664   tree decl;
 665   tree target;
 666 } alias_pair;
 667
 668 /* An initialization priority.  */
 669 typedef unsigned short priority_type;
 670
 671 /* The type of a callback function for walking over tree structure.  */
 672 typedef tree (*walk_tree_fn) (tree *, int *, void *);
 673
 674 /* The type of a callback function that represents a custom walk_tree.  */
 675 typedef tree (*walk_tree_lh) (tree *, int *, tree (*) (tree *, int *, void *),
 676                               void *, struct pointer_set_t*);
 677
 678
 679 /*---------------------------------------------------------------------------
 680                               Main data structures
 681 ---------------------------------------------------------------------------*/
 682 /* A tree node can represent a data type, a variable, an expression
 683    or a statement.  Each node has a TREE_CODE which says what kind of
 684    thing it represents.  Some common codes are:
 685    INTEGER_TYPE -- represents a type of integers.
 686    ARRAY_TYPE -- represents a type of pointer.
 687    VAR_DECL -- represents a declared variable.
 688    INTEGER_CST -- represents a constant integer value.
 689    PLUS_EXPR -- represents a sum (an expression).
 690
 691    As for the contents of a tree node: there are some fields
 692    that all nodes share.  Each TREE_CODE has various special-purpose
 693    fields as well.  The fields of a node are never accessed directly,
 694    always through accessor macros.  */
 695
 696 /* Every kind of tree node starts with this structure,
 697    so all nodes have these fields.
 698
 699    See the accessor macros, defined below, for documentation of the
 700    fields, and the table below which connects the fields and the
 701    accessor macros.  */
 702
 703 struct GTY(()) tree_base {
 704   ENUM_BITFIELD(tree_code) code : 16;
 705
 706   unsigned side_effects_flag : 1;
 707   unsigned constant_flag : 1;
 708   unsigned addressable_flag : 1;
 709   unsigned volatile_flag : 1;
 710   unsigned readonly_flag : 1;
 711   unsigned asm_written_flag: 1;
 712   unsigned nowarning_flag : 1;
 713   unsigned visited : 1;
 714
 715   unsigned used_flag : 1;
 716   unsigned nothrow_flag : 1;
 717   unsigned static_flag : 1;
 718   unsigned public_flag : 1;
 719   unsigned private_flag : 1;
 720   unsigned protected_flag : 1;
 721   unsigned deprecated_flag : 1;
 722   unsigned default_def_flag : 1;
 723
 724   union {
 725     /* The bits in the following structure should only be used with
 726        accessor macros that constrain inputs with tree checking.  */
 727     struct {
 728       unsigned lang_flag_0 : 1;
 729       unsigned lang_flag_1 : 1;
 730       unsigned lang_flag_2 : 1;
 731       unsigned lang_flag_3 : 1;
 732       unsigned lang_flag_4 : 1;
 733       unsigned lang_flag_5 : 1;
 734       unsigned lang_flag_6 : 1;
 735       unsigned saturating_flag : 1;
 736
 737       unsigned unsigned_flag : 1;
 738       unsigned packed_flag : 1;
 739       unsigned user_align : 1;
 740       unsigned nameless_flag : 1;
 741       unsigned spare0 : 4;
 742
 743       unsigned spare1 : 8;
 744
 745       /* This field is only used with TREE_TYPE nodes; the only reason it is
 746          present in tree_base instead of tree_type is to save space.  The size
 747          of the field must be large enough to hold addr_space_t values.  */
 748       unsigned address_space : 8;
 749     } bits;
 750     /* The following fields are present in tree_base to save space.  The
 751        nodes using them do not require any of the flags above and so can
 752        make better use of the 4-byte sized word.  */
 753     /* VEC length.  This field is only used with TREE_VEC.  */
 754     int length;
 755     /* SSA version number.  This field is only used with SSA_NAME.  */
 756     unsigned int version;
 757   } GTY((skip(""))) u;
 758 };
 759
 760 /* The following table lists the uses of each of the above flags and
 761    for which types of nodes they are defined.
 762
 763    addressable_flag:
 764
 765        TREE_ADDRESSABLE in
 766            VAR_DECL, PARM_DECL, RESULT_DECL, FUNCTION_DECL, LABEL_DECL
 767            SSA_NAME
 768            all types
 769            CONSTRUCTOR, IDENTIFIER_NODE
 770            STMT_EXPR
 771
 772        CALL_EXPR_TAILCALL in
 773            CALL_EXPR
 774
 775        CASE_LOW_SEEN in
 776            CASE_LABEL_EXPR
 777
 778        PREDICT_EXPR_OUTCOME in
 779            PREDICT_EXPR
 780
 781    static_flag:
 782
 783        TREE_STATIC in
 784            VAR_DECL, FUNCTION_DECL
 785            CONSTRUCTOR
 786
 787        TREE_NO_TRAMPOLINE in
 788            ADDR_EXPR
 789
 790        BINFO_VIRTUAL_P in
 791            TREE_BINFO
 792
 793        TREE_SYMBOL_REFERENCED in
 794            IDENTIFIER_NODE
 795
 796        CLEANUP_EH_ONLY in
 797            TARGET_EXPR, WITH_CLEANUP_EXPR
 798
 799        TRY_CATCH_IS_CLEANUP in
 800            TRY_CATCH_EXPR
 801
 802        ASM_INPUT_P in
 803            ASM_EXPR
 804
 805        TYPE_REF_CAN_ALIAS_ALL in
 806            POINTER_TYPE, REFERENCE_TYPE
 807
 808        CASE_HIGH_SEEN in
 809            CASE_LABEL_EXPR
 810
 811        ENUM_IS_SCOPED in
 812            ENUMERAL_TYPE
 813
 814        TRANSACTION_EXPR_OUTER in
 815            TRANSACTION_EXPR
 816
 817    public_flag:
 818
 819        TREE_OVERFLOW in
 820            INTEGER_CST, REAL_CST, COMPLEX_CST, VECTOR_CST
 821
 822        TREE_PUBLIC in
 823            VAR_DECL, FUNCTION_DECL
 824            IDENTIFIER_NODE
 825
 826        ASM_VOLATILE_P in
 827            ASM_EXPR
 828
 829        CALL_EXPR_VA_ARG_PACK in
 830            CALL_EXPR
 831
 832        TYPE_CACHED_VALUES_P in
 833            all types
 834
 835        SAVE_EXPR_RESOLVED_P in
 836            SAVE_EXPR
 837
 838        OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE in
 839            OMP_CLAUSE_LASTPRIVATE
 840
 841        OMP_CLAUSE_PRIVATE_DEBUG in
 842            OMP_CLAUSE_PRIVATE
 843
 844        OMP_CLAUSE_LINEAR_NO_COPYIN in
 845            OMP_CLAUSE_LINEAR
 846
 847        OMP_CLAUSE_MAP_ZERO_BIAS_ARRAY_SECTION in
 848            OMP_CLAUSE_MAP
 849
 850        OMP_CLAUSE_REDUCTION_OMP_ORIG_REF in
 851            OMP_CLAUSE_REDUCTION
 852
 853        TRANSACTION_EXPR_RELAXED in
 854            TRANSACTION_EXPR
 855
 856    private_flag:
 857
 858        TREE_PRIVATE in
 859            all decls
 860
 861        CALL_EXPR_RETURN_SLOT_OPT in
 862            CALL_EXPR
 863
 864        OMP_SECTION_LAST in
 865            OMP_SECTION
 866
 867        OMP_PARALLEL_COMBINED in
 868            OMP_PARALLEL
 869
 870        OMP_ATOMIC_SEQ_CST in
 871            OMP_ATOMIC*
 872
 873        OMP_CLAUSE_PRIVATE_OUTER_REF in
 874            OMP_CLAUSE_PRIVATE
 875
 876        OMP_CLAUSE_LINEAR_NO_COPYOUT in
 877            OMP_CLAUSE_LINEAR
 878
 879        TYPE_REF_IS_RVALUE in
 880            REFERENCE_TYPE
 881
 882        ENUM_IS_OPAQUE in
 883            ENUMERAL_TYPE
 884
 885    protected_flag:
 886
 887        TREE_PROTECTED in
 888            BLOCK
 889            all decls
 890
 891        CALL_FROM_THUNK_P and
 892        CALL_ALLOCA_FOR_VAR_P in
 893            CALL_EXPR
 894
 895    side_effects_flag:
 896
 897        TREE_SIDE_EFFECTS in
 898            all expressions
 899            all decls
 900            all constants
 901
 902        FORCED_LABEL in
 903            LABEL_DECL
 904
 905    volatile_flag:
 906
 907        TREE_THIS_VOLATILE in
 908            all expressions
 909            all decls
 910
 911        TYPE_VOLATILE in
 912            all types
 913
 914    readonly_flag:
 915
 916        TREE_READONLY in
 917            all expressions
 918            all decls
 919
 920        TYPE_READONLY in
 921            all types
 922
 923    constant_flag:
 924
 925        TREE_CONSTANT in
 926            all expressions
 927            all decls
 928            all constants
 929
 930        TYPE_SIZES_GIMPLIFIED in
 931            all types
 932
 933    unsigned_flag:
 934
 935        TYPE_UNSIGNED in
 936            all types
 937
 938        DECL_UNSIGNED in
 939            all decls
 940
 941    asm_written_flag:
 942
 943        TREE_ASM_WRITTEN in
 944            VAR_DECL, FUNCTION_DECL, TYPE_DECL
 945            RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE
 946            BLOCK, STRING_CST
 947
 948        SSA_NAME_OCCURS_IN_ABNORMAL_PHI in
 949            SSA_NAME
 950
 951    used_flag:
 952
 953        TREE_USED in
 954            all expressions
 955            all decls
 956            IDENTIFIER_NODE
 957
 958    nothrow_flag:
 959
 960        TREE_NOTHROW in
 961            CALL_EXPR
 962            FUNCTION_DECL
 963
 964        TYPE_ALIGN_OK in
 965            all types
 966
 967        TREE_THIS_NOTRAP in
 968           INDIRECT_REF, MEM_REF, TARGET_MEM_REF, ARRAY_REF, ARRAY_RANGE_REF
 969
 970        SSA_NAME_IN_FREELIST in
 971           SSA_NAME
 972
 973    deprecated_flag:
 974
 975        TREE_DEPRECATED in
 976            all decls
 977            all types
 978
 979        IDENTIFIER_TRANSPARENT_ALIAS in
 980            IDENTIFIER_NODE
 981
 982    visited:
 983
 984        TREE_VISITED in
 985            all trees (used liberally by many passes)
 986
 987    saturating_flag:
 988
 989        TYPE_SATURATING in
 990            all types
 991
 992        VAR_DECL_IS_VIRTUAL_OPERAND in
 993            VAR_DECL
 994
 995    nowarning_flag:
 996
 997        TREE_NO_WARNING in
 998            all expressions
 999            all decls
1000
1001        TYPE_ARTIFICIAL in
1002            all types
1003
1004    default_def_flag:
1005
1006        TYPE_VECTOR_OPAQUE in
1007            VECTOR_TYPE
1008
1009        SSA_NAME_IS_DEFAULT_DEF in
1010            SSA_NAME
1011
1012        DECL_NONLOCAL_FRAME in
1013            VAR_DECL
1014
1015        TYPE_FINAL_P in
1016            RECORD_TYPE, UNION_TYPE and QUAL_UNION_TYPE
1017 */
1018
1019 struct GTY(()) tree_typed {
1020   struct tree_base base;
1021   tree type;
1022 };
1023
1024 struct GTY(()) tree_common {
1025   struct tree_typed typed;
1026   tree chain;
1027 };
1028
1029 struct GTY(()) tree_int_cst {
1030   struct tree_typed typed;
1031   double_int int_cst;
1032 };
1033
1034
1035 struct GTY(()) tree_real_cst {
1036   struct tree_typed typed;
1037   struct real_value * real_cst_ptr;
1038 };
1039
1040 struct GTY(()) tree_fixed_cst {
1041   struct tree_typed typed;
1042   struct fixed_value * fixed_cst_ptr;
1043 };
1044
1045 struct GTY(()) tree_string {
1046   struct tree_typed typed;
1047   int length;
1048   char str[1];
1049 };
1050
1051 struct GTY(()) tree_complex {
1052   struct tree_typed typed;
1053   tree real;
1054   tree imag;
1055 };
1056
1057 struct GTY(()) tree_vector {
1058   struct tree_typed typed;
1059   tree GTY ((length ("TYPE_VECTOR_SUBPARTS (TREE_TYPE ((tree)&%h))"))) elts[1];
1060 };
1061
1062 struct GTY(()) tree_identifier {
1063   struct tree_common common;
1064   struct ht_identifier id;
1065 };
1066
1067 struct GTY(()) tree_list {
1068   struct tree_common common;
1069   tree purpose;
1070   tree value;
1071 };
1072
1073 struct GTY(()) tree_vec {
1074   struct tree_common common;
1075   tree GTY ((length ("TREE_VEC_LENGTH ((tree)&%h)"))) a[1];
1076 };
1077
1078 /* A single element of a CONSTRUCTOR. VALUE holds the actual value of the
1079    element. INDEX can optionally design the position of VALUE: in arrays,
1080    it is the index where VALUE has to be placed; in structures, it is the
1081    FIELD_DECL of the member.  */
1082 typedef struct GTY(()) constructor_elt_d {
1083   tree index;
1084   tree value;
1085 } constructor_elt;
1086
1087 struct GTY(()) tree_constructor {
1088   struct tree_typed typed;
1089   vec<constructor_elt, va_gc> *elts;
1090 };
1091
1092 enum omp_clause_depend_kind
1093 {
1094   OMP_CLAUSE_DEPEND_IN,
1095   OMP_CLAUSE_DEPEND_OUT,
1096   OMP_CLAUSE_DEPEND_INOUT
1097 };
1098
1099 enum omp_clause_map_kind
1100 {
1101   OMP_CLAUSE_MAP_ALLOC,
1102   OMP_CLAUSE_MAP_TO,
1103   OMP_CLAUSE_MAP_FROM,
1104   OMP_CLAUSE_MAP_TOFROM,
1105   /* The following kind is an internal only map kind, used for pointer based
1106      array sections.  OMP_CLAUSE_SIZE for these is not the pointer size,
1107      which is implicitly POINTER_SIZE / BITS_PER_UNIT, but the bias.  */
1108   OMP_CLAUSE_MAP_POINTER
1109 };
1110
1111 enum omp_clause_proc_bind_kind
1112 {
1113   /* Numbers should match omp_proc_bind_t enum in omp.h.  */
1114   OMP_CLAUSE_PROC_BIND_FALSE = 0,
1115   OMP_CLAUSE_PROC_BIND_TRUE = 1,
1116   OMP_CLAUSE_PROC_BIND_MASTER = 2,
1117   OMP_CLAUSE_PROC_BIND_CLOSE = 3,
1118   OMP_CLAUSE_PROC_BIND_SPREAD = 4
1119 };
1120
1121 struct GTY(()) tree_exp {
1122   struct tree_typed typed;
1123   location_t locus;
1124   tree GTY ((special ("tree_exp"),
1125              desc ("TREE_CODE ((tree) &%0)")))
1126     operands[1];
1127 };
1128
1129 /* Immediate use linking structure.  This structure is used for maintaining
1130    a doubly linked list of uses of an SSA_NAME.  */
1131 typedef struct GTY(()) ssa_use_operand_d {
1132   struct ssa_use_operand_d* GTY((skip(""))) prev;
1133   struct ssa_use_operand_d* GTY((skip(""))) next;
1134   /* Immediate uses for a given SSA name are maintained as a cyclic
1135      list.  To recognize the root of this list, the location field
1136      needs to point to the original SSA name.  Since statements and
1137      SSA names are of different data types, we need this union.  See
1138      the explanation in struct immediate_use_iterator_d.  */
1139   union { gimple stmt; tree ssa_name; } GTY((skip(""))) loc;
1140   tree *GTY((skip(""))) use;
1141 } ssa_use_operand_t;
1142
1143 struct GTY(()) tree_ssa_name {
1144   struct tree_typed typed;
1145
1146   /* _DECL wrapped by this SSA name.  */
1147   tree var;
1148
1149   /* Statement that defines this SSA name.  */
1150   gimple def_stmt;
1151
1152   /* Value range information.  */
1153   union ssa_name_info_type {
1154     /* Pointer attributes used for alias analysis.  */
1155     struct GTY ((tag ("0"))) ptr_info_def *ptr_info;
1156     /* Value range attributes used for zero/sign extension elimination.  */
1157     struct GTY ((tag ("1"))) range_info_def *range_info;
1158   } GTY ((desc ("%1.typed.type ?" \
1159                 "!POINTER_TYPE_P (TREE_TYPE ((tree)&%1)) : 2"))) info;
1160
1161   /* Immediate uses list for this SSA_NAME.  */
1162   struct ssa_use_operand_d imm_uses;
1163 };
1164
1165 struct GTY(()) phi_arg_d {
1166   /* imm_use MUST be the first element in struct because we do some
1167      pointer arithmetic with it.  See phi_arg_index_from_use.  */
1168   struct ssa_use_operand_d imm_use;
1169   tree def;
1170   location_t locus;
1171 };
1172
1173 struct GTY(()) tree_omp_clause {
1174   struct tree_common common;
1175   location_t locus;
1176   enum omp_clause_code code;
1177   union omp_clause_subcode {
1178     enum omp_clause_default_kind   default_kind;
1179     enum omp_clause_schedule_kind  schedule_kind;
1180     enum omp_clause_depend_kind    depend_kind;
1181     enum omp_clause_map_kind       map_kind;
1182     enum omp_clause_proc_bind_kind proc_bind_kind;
1183     enum tree_code                 reduction_code;
1184   } GTY ((skip)) subcode;
1185
1186   /* The gimplification of OMP_CLAUSE_REDUCTION_{INIT,MERGE} for omp-low's
1187      usage.  */
1188   gimple_seq gimple_reduction_init;
1189   gimple_seq gimple_reduction_merge;
1190
1191   tree GTY ((length ("omp_clause_num_ops[OMP_CLAUSE_CODE ((tree)&%h)]")))
1192     ops[1];
1193 };
1194
1195 struct GTY(()) tree_block {
1196   struct tree_base base;
1197   tree chain;
1198
1199   unsigned abstract_flag : 1;
1200   unsigned block_num : 31;
1201
1202   location_t locus;
1203
1204   tree vars;
1205   vec<tree, va_gc> *nonlocalized_vars;
1206
1207   tree subblocks;
1208   tree supercontext;
1209   tree abstract_origin;
1210   tree fragment_origin;
1211   tree fragment_chain;
1212 };
1213
1214 struct GTY(()) tree_type_common {
1215   struct tree_common common;
1216   tree size;
1217   tree size_unit;
1218   tree attributes;
1219   unsigned int uid;
1220
1221   unsigned int precision : 10;
1222   unsigned no_force_blk_flag : 1;
1223   unsigned needs_constructing_flag : 1;
1224   unsigned transparent_aggr_flag : 1;
1225   unsigned restrict_flag : 1;
1226   unsigned contains_placeholder_bits : 2;
1227
1228   ENUM_BITFIELD(machine_mode) mode : 8;
1229
1230   unsigned string_flag : 1;
1231   unsigned lang_flag_0 : 1;
1232   unsigned lang_flag_1 : 1;
1233   unsigned lang_flag_2 : 1;
1234   unsigned lang_flag_3 : 1;
1235   unsigned lang_flag_4 : 1;
1236   unsigned lang_flag_5 : 1;
1237   unsigned lang_flag_6 : 1;
1238
1239   unsigned int align;
1240   alias_set_type alias_set;
1241   tree pointer_to;
1242   tree reference_to;
1243   union tree_type_symtab {
1244     int GTY ((tag ("TYPE_SYMTAB_IS_ADDRESS"))) address;
1245     const char * GTY ((tag ("TYPE_SYMTAB_IS_POINTER"))) pointer;
1246     struct die_struct * GTY ((tag ("TYPE_SYMTAB_IS_DIE"))) die;
1247   } GTY ((desc ("debug_hooks->tree_type_symtab_field"))) symtab;
1248   tree name;
1249   tree next_variant;
1250   tree main_variant;
1251   tree context;
1252   tree canonical;
1253 };
1254
1255 struct GTY(()) tree_type_with_lang_specific {
1256   struct tree_type_common common;
1257   /* Points to a structure whose details depend on the language in use.  */
1258   struct lang_type *lang_specific;
1259 };
1260
1261 struct GTY(()) tree_type_non_common {
1262   struct tree_type_with_lang_specific with_lang_specific;
1263   tree values;
1264   tree minval;
1265   tree maxval;
1266   tree binfo;
1267 };
1268
1269 struct GTY (()) tree_binfo {
1270   struct tree_common common;
1271
1272   tree offset;
1273   tree vtable;
1274   tree virtuals;
1275   tree vptr_field;
1276   vec<tree, va_gc> *base_accesses;
1277   tree inheritance;
1278
1279   tree vtt_subvtt;
1280   tree vtt_vptr;
1281
1282   vec<tree, va_gc> base_binfos;
1283 };
1284
1285 struct GTY(()) tree_decl_minimal {
1286   struct tree_common common;
1287   location_t locus;
1288   unsigned int uid;
1289   tree name;
1290   tree context;
1291 };
1292
1293 struct GTY(()) tree_decl_common {
1294   struct tree_decl_minimal common;
1295   tree size;
1296
1297   ENUM_BITFIELD(machine_mode) mode : 8;
1298
1299   unsigned nonlocal_flag : 1;
1300   unsigned virtual_flag : 1;
1301   unsigned ignored_flag : 1;
1302   unsigned abstract_flag : 1;
1303   unsigned artificial_flag : 1;
1304   unsigned preserve_flag: 1;
1305   unsigned debug_expr_is_from : 1;
1306
1307   unsigned lang_flag_0 : 1;
1308   unsigned lang_flag_1 : 1;
1309   unsigned lang_flag_2 : 1;
1310   unsigned lang_flag_3 : 1;
1311   unsigned lang_flag_4 : 1;
1312   unsigned lang_flag_5 : 1;
1313   unsigned lang_flag_6 : 1;
1314   unsigned lang_flag_7 : 1;
1315   unsigned lang_flag_8 : 1;
1316
1317   /* In VAR_DECL and PARM_DECL, this is DECL_REGISTER.  */
1318   unsigned decl_flag_0 : 1;
1319   /* In FIELD_DECL, this is DECL_BIT_FIELD
1320      In VAR_DECL and FUNCTION_DECL, this is DECL_EXTERNAL.
1321      In TYPE_DECL, this is TYPE_DECL_SUPPRESS_DEBUG.  */
1322   unsigned decl_flag_1 : 1;
1323   /* In FIELD_DECL, this is DECL_NONADDRESSABLE_P
1324      In VAR_DECL, PARM_DECL and RESULT_DECL, this is
1325      DECL_HAS_VALUE_EXPR_P.  */
1326   unsigned decl_flag_2 : 1;
1327   /* 1 bit unused.  */
1328   unsigned decl_flag_3 : 1;
1329   /* Logically, these two would go in a theoretical base shared by var and
1330      parm decl. */
1331   unsigned gimple_reg_flag : 1;
1332   /* In VAR_DECL, PARM_DECL and RESULT_DECL, this is DECL_BY_REFERENCE.  */
1333   unsigned decl_by_reference_flag : 1;
1334   /* In a VAR_DECL and PARM_DECL, this is DECL_READ_P.  */
1335   unsigned decl_read_flag : 1;
1336   /* In a VAR_DECL or RESULT_DECL, this is DECL_NONSHAREABLE.  */
1337   unsigned decl_nonshareable_flag : 1;
1338
1339   /* DECL_OFFSET_ALIGN, used only for FIELD_DECLs.  */
1340   unsigned int off_align : 8;
1341
1342   /* 24 bits unused.  */
1343
1344   /* DECL_ALIGN.  It should have the same size as TYPE_ALIGN.  */
1345   unsigned int align;
1346
1347   /* UID for points-to sets, stable over copying from inlining.  */
1348   unsigned int pt_uid;
1349
1350   tree size_unit;
1351   tree initial;
1352   tree attributes;
1353   tree abstract_origin;
1354
1355   /* Points to a structure whose details depend on the language in use.  */
1356   struct lang_decl *lang_specific;
1357 };
1358
1359 struct GTY(()) tree_decl_with_rtl {
1360   struct tree_decl_common common;
1361   rtx rtl;
1362 };
1363
1364 struct GTY(()) tree_field_decl {
1365   struct tree_decl_common common;
1366
1367   tree offset;
1368   tree bit_field_type;
1369   tree qualifier;
1370   tree bit_offset;
1371   tree fcontext;
1372 };
1373
1374 struct GTY(()) tree_label_decl {
1375   struct tree_decl_with_rtl common;
1376   int label_decl_uid;
1377   int eh_landing_pad_nr;
1378 };
1379
1380 struct GTY(()) tree_result_decl {
1381   struct tree_decl_with_rtl common;
1382 };
1383
1384 struct GTY(()) tree_const_decl {
1385   struct tree_decl_common common;
1386 };
1387
1388 struct GTY(()) tree_parm_decl {
1389   struct tree_decl_with_rtl common;
1390   rtx incoming_rtl;
1391 };
1392
1393 struct GTY(()) tree_decl_with_vis {
1394  struct tree_decl_with_rtl common;
1395  tree assembler_name;
1396  tree section_name;
1397  tree comdat_group;
1398
1399  /* Belong to VAR_DECL exclusively.  */
1400  unsigned defer_output : 1;
1401  unsigned hard_register : 1;
1402  unsigned common_flag : 1;
1403  unsigned in_text_section : 1;
1404  unsigned in_constant_pool : 1;
1405  unsigned dllimport_flag : 1;
1406  /* Don't belong to VAR_DECL exclusively.  */
1407  unsigned weak_flag : 1;
1408  /* When SECTION_NAME is implied by -ffunction-section.  */
1409  unsigned implicit_section_name_p : 1;
1410
1411  unsigned seen_in_bind_expr : 1;
1412  unsigned comdat_flag : 1;
1413  ENUM_BITFIELD(symbol_visibility) visibility : 2;
1414  unsigned visibility_specified : 1;
1415  /* Belongs to VAR_DECL exclusively.  */
1416  ENUM_BITFIELD(tls_model) tls_model : 3;
1417
1418  /* Belong to FUNCTION_DECL exclusively.  */
1419  unsigned init_priority_p : 1;
1420  /* Used by C++ only.  Might become a generic decl flag.  */
1421  unsigned shadowed_for_var_p : 1;
1422  /* Belong to FUNCTION_DECL exclusively.  */
1423  unsigned cxx_constructor : 1;
1424  /* Belong to FUNCTION_DECL exclusively.  */
1425  unsigned cxx_destructor : 1;
1426  /* Belong to FUNCTION_DECL exclusively.  */
1427  unsigned final : 1;
1428  /* 11 unused bits. */
1429 };
1430
1431 struct GTY(()) tree_var_decl {
1432   struct tree_decl_with_vis common;
1433 };
1434
1435 struct GTY(()) tree_decl_non_common {
1436   struct tree_decl_with_vis common;
1437   /* C++ uses this in namespaces.  */
1438   tree saved_tree;
1439   /* C++ uses this in templates.  */
1440   tree arguments;
1441   /* Almost all FE's use this.  */
1442   tree result;
1443   /* C++ uses this in namespaces and function_decls.  */
1444   tree vindex;
1445 };
1446
1447 /* FUNCTION_DECL inherits from DECL_NON_COMMON because of the use of the
1448    arguments/result/saved_tree fields by front ends.   It was either inherit
1449    FUNCTION_DECL from non_common, or inherit non_common from FUNCTION_DECL,
1450    which seemed a bit strange.  */
1451
1452 struct GTY(()) tree_function_decl {
1453   struct tree_decl_non_common common;
1454
1455   struct function *f;
1456
1457   /* The personality function. Used for stack unwinding. */
1458   tree personality;
1459
1460   /* Function specific options that are used by this function.  */
1461   tree function_specific_target;        /* target options */
1462   tree function_specific_optimization;  /* optimization options */
1463
1464   /* In a FUNCTION_DECL for which DECL_BUILT_IN holds, this is
1465      DECL_FUNCTION_CODE.  Otherwise unused.
1466      ???  The bitfield needs to be able to hold all target function
1467           codes as well.  */
1468   ENUM_BITFIELD(built_in_function) function_code : 11;
1469   ENUM_BITFIELD(built_in_class) built_in_class : 2;
1470
1471   unsigned static_ctor_flag : 1;
1472   unsigned static_dtor_flag : 1;
1473   unsigned uninlinable : 1;
1474
1475   unsigned possibly_inlined : 1;
1476   unsigned novops_flag : 1;
1477   unsigned returns_twice_flag : 1;
1478   unsigned malloc_flag : 1;
1479   unsigned operator_new_flag : 1;
1480   unsigned declared_inline_flag : 1;
1481   unsigned regdecl_flag : 1;
1482   unsigned no_inline_warning_flag : 1;
1483
1484   unsigned no_instrument_function_entry_exit : 1;
1485   unsigned no_limit_stack : 1;
1486   unsigned disregard_inline_limits : 1;
1487   unsigned pure_flag : 1;
1488   unsigned looping_const_or_pure_flag : 1;
1489   unsigned has_debug_args_flag : 1;
1490   unsigned tm_clone_flag : 1;
1491   unsigned versioned_function : 1;
1492   /* No bits left.  */
1493 };
1494
1495 struct GTY(()) tree_translation_unit_decl {
1496   struct tree_decl_common common;
1497   /* Source language of this translation unit.  Used for DWARF output.  */
1498   const char * GTY((skip(""))) language;
1499   /* TODO: Non-optimization used to build this translation unit.  */
1500   /* TODO: Root of a partial DWARF tree for global types and decls.  */
1501 };
1502
1503 struct GTY(()) tree_type_decl {
1504   struct tree_decl_non_common common;
1505
1506 };
1507
1508 struct GTY ((chain_next ("%h.next"), chain_prev ("%h.prev"))) tree_statement_list_node
1509  {
1510   struct tree_statement_list_node *prev;
1511   struct tree_statement_list_node *next;
1512   tree stmt;
1513 };
1514
1515 struct GTY(()) tree_statement_list
1516  {
1517   struct tree_typed typed;
1518   struct tree_statement_list_node *head;
1519   struct tree_statement_list_node *tail;
1520 };
1521
1522
1523 /* Optimization options used by a function.  */
1524
1525 struct GTY(()) tree_optimization_option {
1526   struct tree_common common;
1527
1528   /* The optimization options used by the user.  */
1529   struct cl_optimization opts;
1530
1531   /* Target optabs for this set of optimization options.  This is of
1532      type `struct target_optabs *'.  */
1533   unsigned char *GTY ((atomic)) optabs;
1534
1535   /* The value of this_target_optabs against which the optabs above were
1536      generated.  */
1537   struct target_optabs *GTY ((skip)) base_optabs;
1538 };
1539
1540 /* Target options used by a function.  */
1541
1542 struct GTY(()) tree_target_option {
1543   struct tree_common common;
1544
1545   /* The optimization options used by the user.  */
1546   struct cl_target_option opts;
1547 };
1548
1549 /* Define the overall contents of a tree node.
1550    It may be any of the structures declared above
1551    for various types of node.  */
1552 union GTY ((ptr_alias (union lang_tree_node),
1553             desc ("tree_node_structure (&%h)"), variable_size)) tree_node {
1554   struct tree_base GTY ((tag ("TS_BASE"))) base;
1555   struct tree_typed GTY ((tag ("TS_TYPED"))) typed;
1556   struct tree_common GTY ((tag ("TS_COMMON"))) common;
1557   struct tree_int_cst GTY ((tag ("TS_INT_CST"))) int_cst;
1558   struct tree_real_cst GTY ((tag ("TS_REAL_CST"))) real_cst;
1559   struct tree_fixed_cst GTY ((tag ("TS_FIXED_CST"))) fixed_cst;
1560   struct tree_vector GTY ((tag ("TS_VECTOR"))) vector;
1561   struct tree_string GTY ((tag ("TS_STRING"))) string;
1562   struct tree_complex GTY ((tag ("TS_COMPLEX"))) complex;
1563   struct tree_identifier GTY ((tag ("TS_IDENTIFIER"))) identifier;
1564   struct tree_decl_minimal GTY((tag ("TS_DECL_MINIMAL"))) decl_minimal;
1565   struct tree_decl_common GTY ((tag ("TS_DECL_COMMON"))) decl_common;
1566   struct tree_decl_with_rtl GTY ((tag ("TS_DECL_WRTL"))) decl_with_rtl;
1567   struct tree_decl_non_common  GTY ((tag ("TS_DECL_NON_COMMON")))
1568     decl_non_common;
1569   struct tree_parm_decl  GTY  ((tag ("TS_PARM_DECL"))) parm_decl;
1570   struct tree_decl_with_vis GTY ((tag ("TS_DECL_WITH_VIS"))) decl_with_vis;
1571   struct tree_var_decl GTY ((tag ("TS_VAR_DECL"))) var_decl;
1572   struct tree_field_decl GTY ((tag ("TS_FIELD_DECL"))) field_decl;
1573   struct tree_label_decl GTY ((tag ("TS_LABEL_DECL"))) label_decl;
1574   struct tree_result_decl GTY ((tag ("TS_RESULT_DECL"))) result_decl;
1575   struct tree_const_decl GTY ((tag ("TS_CONST_DECL"))) const_decl;
1576   struct tree_type_decl GTY ((tag ("TS_TYPE_DECL"))) type_decl;
1577   struct tree_function_decl GTY ((tag ("TS_FUNCTION_DECL"))) function_decl;
1578   struct tree_translation_unit_decl GTY ((tag ("TS_TRANSLATION_UNIT_DECL")))
1579     translation_unit_decl;
1580   struct tree_type_common GTY ((tag ("TS_TYPE_COMMON"))) type_common;
1581   struct tree_type_with_lang_specific GTY ((tag ("TS_TYPE_WITH_LANG_SPECIFIC")))
1582     type_with_lang_specific;
1583   struct tree_type_non_common GTY ((tag ("TS_TYPE_NON_COMMON")))
1584     type_non_common;
1585   struct tree_list GTY ((tag ("TS_LIST"))) list;
1586   struct tree_vec GTY ((tag ("TS_VEC"))) vec;
1587   struct tree_exp GTY ((tag ("TS_EXP"))) exp;
1588   struct tree_ssa_name GTY ((tag ("TS_SSA_NAME"))) ssa_name;
1589   struct tree_block GTY ((tag ("TS_BLOCK"))) block;
1590   struct tree_binfo GTY ((tag ("TS_BINFO"))) binfo;
1591   struct tree_statement_list GTY ((tag ("TS_STATEMENT_LIST"))) stmt_list;
1592   struct tree_constructor GTY ((tag ("TS_CONSTRUCTOR"))) constructor;
1593   struct tree_omp_clause GTY ((tag ("TS_OMP_CLAUSE"))) omp_clause;
1594   struct tree_optimization_option GTY ((tag ("TS_OPTIMIZATION"))) optimization;
1595   struct tree_target_option GTY ((tag ("TS_TARGET_OPTION"))) target_option;
1596 };
1597
1598 /* Structure describing an attribute and a function to handle it.  */
1599 struct attribute_spec {
1600   /* The name of the attribute (without any leading or trailing __),
1601      or NULL to mark the end of a table of attributes.  */
1602   const char *name;
1603   /* The minimum length of the list of arguments of the attribute.  */
1604   int min_length;
1605   /* The maximum length of the list of arguments of the attribute
1606      (-1 for no maximum).  */
1607   int max_length;
1608   /* Whether this attribute requires a DECL.  If it does, it will be passed
1609      from types of DECLs, function return types and array element types to
1610      the DECLs, function types and array types respectively; but when
1611      applied to a type in any other circumstances, it will be ignored with
1612      a warning.  (If greater control is desired for a given attribute,
1613      this should be false, and the flags argument to the handler may be
1614      used to gain greater control in that case.)  */
1615   bool decl_required;
1616   /* Whether this attribute requires a type.  If it does, it will be passed
1617      from a DECL to the type of that DECL.  */
1618   bool type_required;
1619   /* Whether this attribute requires a function (or method) type.  If it does,
1620      it will be passed from a function pointer type to the target type,
1621      and from a function return type (which is not itself a function
1622      pointer type) to the function type.  */
1623   bool function_type_required;
1624   /* Function to handle this attribute.  NODE points to the node to which
1625      the attribute is to be applied.  If a DECL, it should be modified in
1626      place; if a TYPE, a copy should be created.  NAME is the name of the
1627      attribute (possibly with leading or trailing __).  ARGS is the TREE_LIST
1628      of the arguments (which may be NULL).  FLAGS gives further information
1629      about the context of the attribute.  Afterwards, the attributes will
1630      be added to the DECL_ATTRIBUTES or TYPE_ATTRIBUTES, as appropriate,
1631      unless *NO_ADD_ATTRS is set to true (which should be done on error,
1632      as well as in any other cases when the attributes should not be added
1633      to the DECL or TYPE).  Depending on FLAGS, any attributes to be
1634      applied to another type or DECL later may be returned;
1635      otherwise the return value should be NULL_TREE.  This pointer may be
1636      NULL if no special handling is required beyond the checks implied
1637      by the rest of this structure.  */
1638   tree (*handler) (tree *node, tree name, tree args,
1639                    int flags, bool *no_add_attrs);
1640   /* Specifies if attribute affects type's identity.  */
1641   bool affects_type_identity;
1642 };
1643
1644 /* These functions allow a front-end to perform a manual layout of a
1645    RECORD_TYPE.  (For instance, if the placement of subsequent fields
1646    depends on the placement of fields so far.)  Begin by calling
1647    start_record_layout.  Then, call place_field for each of the
1648    fields.  Then, call finish_record_layout.  See layout_type for the
1649    default way in which these functions are used.  */
1650 typedef struct record_layout_info_s {
1651   /* The RECORD_TYPE that we are laying out.  */
1652   tree t;
1653   /* The offset into the record so far, in bytes, not including bits in
1654      BITPOS.  */
1655   tree offset;
1656   /* The last known alignment of SIZE.  */
1657   unsigned int offset_align;
1658   /* The bit position within the last OFFSET_ALIGN bits, in bits.  */
1659   tree bitpos;
1660   /* The alignment of the record so far, in bits.  */
1661   unsigned int record_align;
1662   /* The alignment of the record so far, ignoring #pragma pack and
1663      __attribute__ ((packed)), in bits.  */
1664   unsigned int unpacked_align;
1665   /* The previous field laid out.  */
1666   tree prev_field;
1667   /* The static variables (i.e., class variables, as opposed to
1668      instance variables) encountered in T.  */
1669   vec<tree, va_gc> *pending_statics;
1670   /* Bits remaining in the current alignment group */
1671   int remaining_in_alignment;
1672   /* True if we've seen a packed field that didn't have normal
1673      alignment anyway.  */
1674   int packed_maybe_necessary;
1675 } *record_layout_info;
1676
1677 /* Iterator for going through the function arguments.  */
1678 struct function_args_iterator {
1679   tree next;                    /* TREE_LIST pointing to the next argument */
1680 };
1681
1682 /* Structures to map from a tree to another tree.  */
1683 struct GTY(()) tree_map_base {
1684   tree from;
1685 };
1686
1687 /* Map from a tree to another tree.  */
1688
1689 struct GTY(()) tree_map {
1690   struct tree_map_base base;
1691   unsigned int hash;
1692   tree to;
1693 };
1694
1695 /* Map from a decl tree to another tree.  */
1696 struct GTY(()) tree_decl_map {
1697   struct tree_map_base base;
1698   tree to;
1699 };
1700
1701 /* Map from a tree to an int.  */
1702 struct GTY(()) tree_int_map {
1703   struct tree_map_base base;
1704   unsigned int to;
1705 };
1706
1707 /* Map from a tree to initialization/finalization priorities.  */
1708 struct GTY(()) tree_priority_map {
1709   struct tree_map_base base;
1710   priority_type init;
1711   priority_type fini;
1712 };
1713
1714 /* Map from a decl tree to a tree vector.  */
1715 struct GTY(()) tree_vec_map {
1716   struct tree_map_base base;
1717   vec<tree, va_gc> *to;
1718 };
1719
1720 /* Abstract iterators for CALL_EXPRs.  These static inline definitions
1721    have to go towards the end of tree.h so that union tree_node is fully
1722    defined by this point.  */
1723
1724 /* Structure containing iterator state.  */
1725 struct call_expr_arg_iterator {
1726   tree t;       /* the call_expr */
1727   int n;        /* argument count */
1728   int i;        /* next argument index */
1729 };
1730
1731 struct const_call_expr_arg_iterator {
1732   const_tree t; /* the call_expr */
1733   int n;        /* argument count */
1734   int i;        /* next argument index */
1735 };
1736
1737 /* The builtin_info structure holds the FUNCTION_DECL of the standard builtin
1738    function, and a flag that says if the function is available implicitly, or
1739    whether the user has to code explicit calls to __builtin_<xxx>.  */
1740 struct GTY(()) builtin_info_type {
1741   tree decl[(int)END_BUILTINS];
1742   bool implicit_p[(int)END_BUILTINS];
1743 };
1744
1745
1746 /*---------------------------------------------------------------------------
1747                                 Global variables
1748 ---------------------------------------------------------------------------*/
1749 /* Matrix describing the structures contained in a given tree code.  */
1750 extern unsigned char tree_contains_struct[MAX_TREE_CODES][64];
1751
1752 /* Class of tree given its code.  */
1753 extern const enum tree_code_class tree_code_type[];
1754
1755 /* Each tree code class has an associated string representation.
1756    These must correspond to the tree_code_class entries.  */
1757 extern const char *const tree_code_class_strings[];
1758
1759 /* Number of argument-words in each kind of tree-node.  */
1760 extern const unsigned char tree_code_length[];
1761
1762 /* Vector of all alias pairs for global symbols.  */
1763 extern GTY(()) vec<alias_pair, va_gc> *alias_pairs;
1764
1765 /* Names of all the built_in classes.  */
1766 extern const char *const built_in_class_names[BUILT_IN_LAST];
1767
1768 /* Names of all the built_in functions.  */
1769 extern const char * built_in_names[(int) END_BUILTINS];
1770
1771 /* Number of operands and names for each OMP_CLAUSE node.  */
1772 extern unsigned const char omp_clause_num_ops[];
1773 extern const char * const omp_clause_code_name[];
1774
1775 /* A vector of all translation-units.  */
1776 extern GTY (()) vec<tree, va_gc> *all_translation_units;
1777
1778 /* Vector of standard trees used by the C compiler.  */
1779 extern GTY(()) tree global_trees[TI_MAX];
1780
1781 /* The standard C integer types.  Use integer_type_kind to index into
1782    this array.  */
1783 extern GTY(()) tree integer_types[itk_none];
1784
1785 /* Types used to represent sizes.  */
1786 extern GTY(()) tree sizetype_tab[(int) stk_type_kind_last];
1787
1788 /* Arrays for keeping track of tree node statistics.  */
1789 extern int tree_node_counts[];
1790 extern int tree_node_sizes[];
1791
1792 /* True if we are in gimple form and the actions of the folders need to
1793    be restricted.  False if we are not in gimple form and folding is not
1794    restricted to creating gimple expressions.  */
1795 extern bool in_gimple_form;
1796
1797 /* Functional interface to the builtin functions.  */
1798 extern GTY(()) builtin_info_type builtin_info;
1799
1800 /* If nonzero, an upper limit on alignment of structure fields, in bits,  */
1801 extern unsigned int maximum_field_alignment;
1802
1803 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
1804    Zero means allow extended lvalues.  */
1805 extern int pedantic_lvalues;
1806
1807 /* Points to the FUNCTION_DECL of the function whose body we are reading.  */
1808 extern GTY(()) tree current_function_decl;
1809
1810 /* Nonzero means a FUNC_BEGIN label was emitted.  */
1811 extern GTY(()) const char * current_function_func_begin_label;
1812
1813 #endif  // GCC_TREE_CORE_H