gcc/tree-core.h

   1 /* Core data structures for the 'tree' type.
   2    Copyright (C) 1989-2014 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   OMP_CLAUSE_SCHEDULE_LAST
 355 };
 356
 357 enum omp_clause_default_kind {
 358   OMP_CLAUSE_DEFAULT_UNSPECIFIED,
 359   OMP_CLAUSE_DEFAULT_SHARED,
 360   OMP_CLAUSE_DEFAULT_NONE,
 361   OMP_CLAUSE_DEFAULT_PRIVATE,
 362   OMP_CLAUSE_DEFAULT_FIRSTPRIVATE,
 363   OMP_CLAUSE_DEFAULT_LAST
 364 };
 365
 366 /* There is a TYPE_QUAL value for each type qualifier.  They can be
 367    combined by bitwise-or to form the complete set of qualifiers for a
 368    type.  */
 369 enum cv_qualifier {
 370   TYPE_UNQUALIFIED   = 0x0,
 371   TYPE_QUAL_CONST    = 0x1,
 372   TYPE_QUAL_VOLATILE = 0x2,
 373   TYPE_QUAL_RESTRICT = 0x4,
 374   TYPE_QUAL_ATOMIC   = 0x8
 375 };
 376
 377 /* Enumerate visibility settings.  */
 378 #ifndef SYMBOL_VISIBILITY_DEFINED
 379 #define SYMBOL_VISIBILITY_DEFINED
 380 enum symbol_visibility {
 381   VISIBILITY_DEFAULT,
 382   VISIBILITY_PROTECTED,
 383   VISIBILITY_HIDDEN,
 384   VISIBILITY_INTERNAL
 385 };
 386 #endif  // SYMBOL_VISIBILITY_DEFINED
 387
 388 /* Standard named or nameless data types of the C compiler.  */
 389 enum tree_index {
 390   TI_ERROR_MARK,
 391   TI_INTQI_TYPE,
 392   TI_INTHI_TYPE,
 393   TI_INTSI_TYPE,
 394   TI_INTDI_TYPE,
 395   TI_INTTI_TYPE,
 396
 397   TI_UINTQI_TYPE,
 398   TI_UINTHI_TYPE,
 399   TI_UINTSI_TYPE,
 400   TI_UINTDI_TYPE,
 401   TI_UINTTI_TYPE,
 402
 403   TI_ATOMICQI_TYPE,
 404   TI_ATOMICHI_TYPE,
 405   TI_ATOMICSI_TYPE,
 406   TI_ATOMICDI_TYPE,
 407   TI_ATOMICTI_TYPE,
 408
 409   TI_UINT16_TYPE,
 410   TI_UINT32_TYPE,
 411   TI_UINT64_TYPE,
 412
 413   TI_VOID,
 414
 415   TI_INTEGER_ZERO,
 416   TI_INTEGER_ONE,
 417   TI_INTEGER_THREE,
 418   TI_INTEGER_MINUS_ONE,
 419   TI_NULL_POINTER,
 420
 421   TI_SIZE_ZERO,
 422   TI_SIZE_ONE,
 423
 424   TI_BITSIZE_ZERO,
 425   TI_BITSIZE_ONE,
 426   TI_BITSIZE_UNIT,
 427
 428   TI_PUBLIC,
 429   TI_PROTECTED,
 430   TI_PRIVATE,
 431
 432   TI_BOOLEAN_FALSE,
 433   TI_BOOLEAN_TRUE,
 434
 435   TI_COMPLEX_INTEGER_TYPE,
 436   TI_COMPLEX_FLOAT_TYPE,
 437   TI_COMPLEX_DOUBLE_TYPE,
 438   TI_COMPLEX_LONG_DOUBLE_TYPE,
 439
 440   TI_FLOAT_TYPE,
 441   TI_DOUBLE_TYPE,
 442   TI_LONG_DOUBLE_TYPE,
 443
 444   TI_FLOAT_PTR_TYPE,
 445   TI_DOUBLE_PTR_TYPE,
 446   TI_LONG_DOUBLE_PTR_TYPE,
 447   TI_INTEGER_PTR_TYPE,
 448
 449   TI_VOID_TYPE,
 450   TI_PTR_TYPE,
 451   TI_CONST_PTR_TYPE,
 452   TI_SIZE_TYPE,
 453   TI_PID_TYPE,
 454   TI_PTRDIFF_TYPE,
 455   TI_VA_LIST_TYPE,
 456   TI_VA_LIST_GPR_COUNTER_FIELD,
 457   TI_VA_LIST_FPR_COUNTER_FIELD,
 458   TI_BOOLEAN_TYPE,
 459   TI_FILEPTR_TYPE,
 460   TI_POINTER_SIZED_TYPE,
 461
 462   TI_DFLOAT32_TYPE,
 463   TI_DFLOAT64_TYPE,
 464   TI_DFLOAT128_TYPE,
 465   TI_DFLOAT32_PTR_TYPE,
 466   TI_DFLOAT64_PTR_TYPE,
 467   TI_DFLOAT128_PTR_TYPE,
 468
 469   TI_VOID_LIST_NODE,
 470
 471   TI_MAIN_IDENTIFIER,
 472
 473   TI_SAT_SFRACT_TYPE,
 474   TI_SAT_FRACT_TYPE,
 475   TI_SAT_LFRACT_TYPE,
 476   TI_SAT_LLFRACT_TYPE,
 477   TI_SAT_USFRACT_TYPE,
 478   TI_SAT_UFRACT_TYPE,
 479   TI_SAT_ULFRACT_TYPE,
 480   TI_SAT_ULLFRACT_TYPE,
 481   TI_SFRACT_TYPE,
 482   TI_FRACT_TYPE,
 483   TI_LFRACT_TYPE,
 484   TI_LLFRACT_TYPE,
 485   TI_USFRACT_TYPE,
 486   TI_UFRACT_TYPE,
 487   TI_ULFRACT_TYPE,
 488   TI_ULLFRACT_TYPE,
 489   TI_SAT_SACCUM_TYPE,
 490   TI_SAT_ACCUM_TYPE,
 491   TI_SAT_LACCUM_TYPE,
 492   TI_SAT_LLACCUM_TYPE,
 493   TI_SAT_USACCUM_TYPE,
 494   TI_SAT_UACCUM_TYPE,
 495   TI_SAT_ULACCUM_TYPE,
 496   TI_SAT_ULLACCUM_TYPE,
 497   TI_SACCUM_TYPE,
 498   TI_ACCUM_TYPE,
 499   TI_LACCUM_TYPE,
 500   TI_LLACCUM_TYPE,
 501   TI_USACCUM_TYPE,
 502   TI_UACCUM_TYPE,
 503   TI_ULACCUM_TYPE,
 504   TI_ULLACCUM_TYPE,
 505   TI_QQ_TYPE,
 506   TI_HQ_TYPE,
 507   TI_SQ_TYPE,
 508   TI_DQ_TYPE,
 509   TI_TQ_TYPE,
 510   TI_UQQ_TYPE,
 511   TI_UHQ_TYPE,
 512   TI_USQ_TYPE,
 513   TI_UDQ_TYPE,
 514   TI_UTQ_TYPE,
 515   TI_SAT_QQ_TYPE,
 516   TI_SAT_HQ_TYPE,
 517   TI_SAT_SQ_TYPE,
 518   TI_SAT_DQ_TYPE,
 519   TI_SAT_TQ_TYPE,
 520   TI_SAT_UQQ_TYPE,
 521   TI_SAT_UHQ_TYPE,
 522   TI_SAT_USQ_TYPE,
 523   TI_SAT_UDQ_TYPE,
 524   TI_SAT_UTQ_TYPE,
 525   TI_HA_TYPE,
 526   TI_SA_TYPE,
 527   TI_DA_TYPE,
 528   TI_TA_TYPE,
 529   TI_UHA_TYPE,
 530   TI_USA_TYPE,
 531   TI_UDA_TYPE,
 532   TI_UTA_TYPE,
 533   TI_SAT_HA_TYPE,
 534   TI_SAT_SA_TYPE,
 535   TI_SAT_DA_TYPE,
 536   TI_SAT_TA_TYPE,
 537   TI_SAT_UHA_TYPE,
 538   TI_SAT_USA_TYPE,
 539   TI_SAT_UDA_TYPE,
 540   TI_SAT_UTA_TYPE,
 541
 542   TI_OPTIMIZATION_DEFAULT,
 543   TI_OPTIMIZATION_CURRENT,
 544   TI_TARGET_OPTION_DEFAULT,
 545   TI_TARGET_OPTION_CURRENT,
 546   TI_CURRENT_TARGET_PRAGMA,
 547   TI_CURRENT_OPTIMIZE_PRAGMA,
 548
 549   TI_MAX
 550 };
 551
 552 /* An enumeration of the standard C integer types.  These must be
 553    ordered so that shorter types appear before longer ones, and so
 554    that signed types appear before unsigned ones, for the correct
 555    functioning of interpret_integer() in c-lex.c.  */
 556 enum integer_type_kind {
 557   itk_char,
 558   itk_signed_char,
 559   itk_unsigned_char,
 560   itk_short,
 561   itk_unsigned_short,
 562   itk_int,
 563   itk_unsigned_int,
 564   itk_long,
 565   itk_unsigned_long,
 566   itk_long_long,
 567   itk_unsigned_long_long,
 568   itk_int128,
 569   itk_unsigned_int128,
 570   itk_none
 571 };
 572
 573 /* A pointer-to-function member type looks like:
 574
 575      struct {
 576        __P __pfn;
 577        ptrdiff_t __delta;
 578      };
 579
 580    If __pfn is NULL, it is a NULL pointer-to-member-function.
 581
 582    (Because the vtable is always the first thing in the object, we
 583    don't need its offset.)  If the function is virtual, then PFN is
 584    one plus twice the index into the vtable; otherwise, it is just a
 585    pointer to the function.
 586
 587    Unfortunately, using the lowest bit of PFN doesn't work in
 588    architectures that don't impose alignment requirements on function
 589    addresses, or that use the lowest bit to tell one ISA from another,
 590    for example.  For such architectures, we use the lowest bit of
 591    DELTA instead of the lowest bit of the PFN, and DELTA will be
 592    multiplied by 2.  */
 593 enum ptrmemfunc_vbit_where_t {
 594   ptrmemfunc_vbit_in_pfn,
 595   ptrmemfunc_vbit_in_delta
 596 };
 597
 598 /* Flags that may be passed in the third argument of decl_attributes, and
 599    to handler functions for attributes.  */
 600 enum attribute_flags {
 601   /* The type passed in is the type of a DECL, and any attributes that
 602      should be passed in again to be applied to the DECL rather than the
 603      type should be returned.  */
 604   ATTR_FLAG_DECL_NEXT = 1,
 605   /* The type passed in is a function return type, and any attributes that
 606      should be passed in again to be applied to the function type rather
 607      than the return type should be returned.  */
 608   ATTR_FLAG_FUNCTION_NEXT = 2,
 609   /* The type passed in is an array element type, and any attributes that
 610      should be passed in again to be applied to the array type rather
 611      than the element type should be returned.  */
 612   ATTR_FLAG_ARRAY_NEXT = 4,
 613   /* The type passed in is a structure, union or enumeration type being
 614      created, and should be modified in place.  */
 615   ATTR_FLAG_TYPE_IN_PLACE = 8,
 616   /* The attributes are being applied by default to a library function whose
 617      name indicates known behavior, and should be silently ignored if they
 618      are not in fact compatible with the function type.  */
 619   ATTR_FLAG_BUILT_IN = 16,
 620   /* A given attribute has been parsed as a C++-11 attribute.  */
 621   ATTR_FLAG_CXX11 = 32
 622 };
 623
 624 /* Types used to represent sizes.  */
 625 enum size_type_kind {
 626   stk_sizetype,         /* Normal representation of sizes in bytes.  */
 627   stk_ssizetype,        /* Signed representation of sizes in bytes.  */
 628   stk_bitsizetype,      /* Normal representation of sizes in bits.  */
 629   stk_sbitsizetype,     /* Signed representation of sizes in bits.  */
 630   stk_type_kind_last
 631 };
 632
 633 enum operand_equal_flag {
 634   OEP_ONLY_CONST = 1,
 635   OEP_PURE_SAME = 2,
 636   OEP_CONSTANT_ADDRESS_OF = 4
 637 };
 638
 639 /* Enum and arrays used for tree allocation stats.
 640    Keep in sync with tree.c:tree_node_kind_names.  */
 641 enum tree_node_kind {
 642   d_kind,
 643   t_kind,
 644   b_kind,
 645   s_kind,
 646   r_kind,
 647   e_kind,
 648   c_kind,
 649   id_kind,
 650   vec_kind,
 651   binfo_kind,
 652   ssa_name_kind,
 653   constr_kind,
 654   x_kind,
 655   lang_decl,
 656   lang_type,
 657   omp_clause_kind,
 658   all_kinds
 659 };
 660
 661 enum annot_expr_kind {
 662   annot_expr_ivdep_kind,
 663   annot_expr_no_vector_kind,
 664   annot_expr_vector_kind,
 665   annot_expr_kind_last
 666 };
 667
 668
 669 /*---------------------------------------------------------------------------
 670                                 Type definitions
 671 ---------------------------------------------------------------------------*/
 672 /* When processing aliases at the symbol table level, we need the
 673    declaration of target. For this reason we need to queue aliases and
 674    process them after all declarations has been produced.  */
 675 struct GTY(()) alias_pair {
 676   tree decl;
 677   tree target;
 678 };
 679
 680 /* An initialization priority.  */
 681 typedef unsigned short priority_type;
 682
 683 /* The type of a callback function for walking over tree structure.  */
 684 typedef tree (*walk_tree_fn) (tree *, int *, void *);
 685
 686 /* The type of a callback function that represents a custom walk_tree.  */
 687 typedef tree (*walk_tree_lh) (tree *, int *, tree (*) (tree *, int *, void *),
 688                               void *, struct pointer_set_t*);
 689
 690
 691 /*---------------------------------------------------------------------------
 692                               Main data structures
 693 ---------------------------------------------------------------------------*/
 694 /* A tree node can represent a data type, a variable, an expression
 695    or a statement.  Each node has a TREE_CODE which says what kind of
 696    thing it represents.  Some common codes are:
 697    INTEGER_TYPE -- represents a type of integers.
 698    ARRAY_TYPE -- represents a type of pointer.
 699    VAR_DECL -- represents a declared variable.
 700    INTEGER_CST -- represents a constant integer value.
 701    PLUS_EXPR -- represents a sum (an expression).
 702
 703    As for the contents of a tree node: there are some fields
 704    that all nodes share.  Each TREE_CODE has various special-purpose
 705    fields as well.  The fields of a node are never accessed directly,
 706    always through accessor macros.  */
 707
 708 /* Every kind of tree node starts with this structure,
 709    so all nodes have these fields.
 710
 711    See the accessor macros, defined below, for documentation of the
 712    fields, and the table below which connects the fields and the
 713    accessor macros.  */
 714
 715 struct GTY(()) tree_base {
 716   ENUM_BITFIELD(tree_code) code : 16;
 717
 718   unsigned side_effects_flag : 1;
 719   unsigned constant_flag : 1;
 720   unsigned addressable_flag : 1;
 721   unsigned volatile_flag : 1;
 722   unsigned readonly_flag : 1;
 723   unsigned asm_written_flag: 1;
 724   unsigned nowarning_flag : 1;
 725   unsigned visited : 1;
 726
 727   unsigned used_flag : 1;
 728   unsigned nothrow_flag : 1;
 729   unsigned static_flag : 1;
 730   unsigned public_flag : 1;
 731   unsigned private_flag : 1;
 732   unsigned protected_flag : 1;
 733   unsigned deprecated_flag : 1;
 734   unsigned default_def_flag : 1;
 735
 736   union {
 737     /* The bits in the following structure should only be used with
 738        accessor macros that constrain inputs with tree checking.  */
 739     struct {
 740       unsigned lang_flag_0 : 1;
 741       unsigned lang_flag_1 : 1;
 742       unsigned lang_flag_2 : 1;
 743       unsigned lang_flag_3 : 1;
 744       unsigned lang_flag_4 : 1;
 745       unsigned lang_flag_5 : 1;
 746       unsigned lang_flag_6 : 1;
 747       unsigned saturating_flag : 1;
 748
 749       unsigned unsigned_flag : 1;
 750       unsigned packed_flag : 1;
 751       unsigned user_align : 1;
 752       unsigned nameless_flag : 1;
 753       unsigned atomic_flag : 1;
 754       unsigned spare0 : 3;
 755
 756       unsigned spare1 : 8;
 757
 758       /* This field is only used with TREE_TYPE nodes; the only reason it is
 759          present in tree_base instead of tree_type is to save space.  The size
 760          of the field must be large enough to hold addr_space_t values.  */
 761       unsigned address_space : 8;
 762     } bits;
 763
 764     /* The following fields are present in tree_base to save space.  The
 765        nodes using them do not require any of the flags above and so can
 766        make better use of the 4-byte sized word.  */
 767
 768     /* The number of HOST_WIDE_INTs in an INTEGER_CST.  */
 769     struct {
 770       /* The number of HOST_WIDE_INTs if the INTEGER_CST is accessed in
 771          its native precision.  */
 772       unsigned char unextended;
 773
 774       /* The number of HOST_WIDE_INTs if the INTEGER_CST is extended to
 775          wider precisions based on its TYPE_SIGN.  */
 776       unsigned char extended;
 777
 778       /* The number of HOST_WIDE_INTs if the INTEGER_CST is accessed in
 779          offset_int precision, with smaller integers being extended
 780          according to their TYPE_SIGN.  This is equal to one of the two
 781          fields above but is cached for speed.  */
 782       unsigned char offset;
 783     } int_length;
 784
 785     /* VEC length.  This field is only used with TREE_VEC.  */
 786     int length;
 787
 788     /* SSA version number.  This field is only used with SSA_NAME.  */
 789     unsigned int version;
 790   } GTY((skip(""))) u;
 791 };
 792
 793 /* The following table lists the uses of each of the above flags and
 794    for which types of nodes they are defined.
 795
 796    addressable_flag:
 797
 798        TREE_ADDRESSABLE in
 799            VAR_DECL, PARM_DECL, RESULT_DECL, FUNCTION_DECL, LABEL_DECL
 800            SSA_NAME
 801            all types
 802            CONSTRUCTOR, IDENTIFIER_NODE
 803            STMT_EXPR
 804
 805        CALL_EXPR_TAILCALL in
 806            CALL_EXPR
 807
 808        CASE_LOW_SEEN in
 809            CASE_LABEL_EXPR
 810
 811        PREDICT_EXPR_OUTCOME in
 812            PREDICT_EXPR
 813
 814    static_flag:
 815
 816        TREE_STATIC in
 817            VAR_DECL, FUNCTION_DECL
 818            CONSTRUCTOR
 819
 820        TREE_NO_TRAMPOLINE in
 821            ADDR_EXPR
 822
 823        BINFO_VIRTUAL_P in
 824            TREE_BINFO
 825
 826        TREE_SYMBOL_REFERENCED in
 827            IDENTIFIER_NODE
 828
 829        CLEANUP_EH_ONLY in
 830            TARGET_EXPR, WITH_CLEANUP_EXPR
 831
 832        TRY_CATCH_IS_CLEANUP in
 833            TRY_CATCH_EXPR
 834
 835        ASM_INPUT_P in
 836            ASM_EXPR
 837
 838        TYPE_REF_CAN_ALIAS_ALL in
 839            POINTER_TYPE, REFERENCE_TYPE
 840
 841        CASE_HIGH_SEEN in
 842            CASE_LABEL_EXPR
 843
 844        ENUM_IS_SCOPED in
 845            ENUMERAL_TYPE
 846
 847        TRANSACTION_EXPR_OUTER in
 848            TRANSACTION_EXPR
 849
 850        SSA_NAME_ANTI_RANGE_P in
 851            SSA_NAME
 852
 853    public_flag:
 854
 855        TREE_OVERFLOW in
 856            INTEGER_CST, REAL_CST, COMPLEX_CST, VECTOR_CST
 857
 858        TREE_PUBLIC in
 859            VAR_DECL, FUNCTION_DECL
 860            IDENTIFIER_NODE
 861
 862        CONSTRUCTOR_NO_CLEARING in
 863            CONSTRUCTOR
 864
 865        ASM_VOLATILE_P in
 866            ASM_EXPR
 867
 868        CALL_EXPR_VA_ARG_PACK in
 869            CALL_EXPR
 870
 871        TYPE_CACHED_VALUES_P in
 872            all types
 873
 874        SAVE_EXPR_RESOLVED_P in
 875            SAVE_EXPR
 876
 877        OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE in
 878            OMP_CLAUSE_LASTPRIVATE
 879
 880        OMP_CLAUSE_PRIVATE_DEBUG in
 881            OMP_CLAUSE_PRIVATE
 882
 883        OMP_CLAUSE_LINEAR_NO_COPYIN in
 884            OMP_CLAUSE_LINEAR
 885
 886        OMP_CLAUSE_MAP_ZERO_BIAS_ARRAY_SECTION in
 887            OMP_CLAUSE_MAP
 888
 889        OMP_CLAUSE_REDUCTION_OMP_ORIG_REF in
 890            OMP_CLAUSE_REDUCTION
 891
 892        TRANSACTION_EXPR_RELAXED in
 893            TRANSACTION_EXPR
 894
 895    private_flag:
 896
 897        TREE_PRIVATE in
 898            all decls
 899
 900        CALL_EXPR_RETURN_SLOT_OPT in
 901            CALL_EXPR
 902
 903        OMP_SECTION_LAST in
 904            OMP_SECTION
 905
 906        OMP_PARALLEL_COMBINED in
 907            OMP_PARALLEL
 908
 909        OMP_ATOMIC_SEQ_CST in
 910            OMP_ATOMIC*
 911
 912        OMP_CLAUSE_PRIVATE_OUTER_REF in
 913            OMP_CLAUSE_PRIVATE
 914
 915        OMP_CLAUSE_LINEAR_NO_COPYOUT in
 916            OMP_CLAUSE_LINEAR
 917
 918        TYPE_REF_IS_RVALUE in
 919            REFERENCE_TYPE
 920
 921        ENUM_IS_OPAQUE in
 922            ENUMERAL_TYPE
 923
 924    protected_flag:
 925
 926        TREE_PROTECTED in
 927            BLOCK
 928            all decls
 929
 930        CALL_FROM_THUNK_P and
 931        CALL_ALLOCA_FOR_VAR_P in
 932            CALL_EXPR
 933
 934        OMP_CLAUSE_LINEAR_VARIABLE_STRIDE in
 935            OMP_CLAUSE_LINEAR
 936
 937    side_effects_flag:
 938
 939        TREE_SIDE_EFFECTS in
 940            all expressions
 941            all decls
 942            all constants
 943
 944        FORCED_LABEL in
 945            LABEL_DECL
 946
 947    volatile_flag:
 948
 949        TREE_THIS_VOLATILE in
 950            all expressions
 951            all decls
 952
 953        TYPE_VOLATILE in
 954            all types
 955
 956    readonly_flag:
 957
 958        TREE_READONLY in
 959            all expressions
 960            all decls
 961
 962        TYPE_READONLY in
 963            all types
 964
 965    constant_flag:
 966
 967        TREE_CONSTANT in
 968            all expressions
 969            all decls
 970            all constants
 971
 972        TYPE_SIZES_GIMPLIFIED in
 973            all types
 974
 975    unsigned_flag:
 976
 977        TYPE_UNSIGNED in
 978            all types
 979
 980        DECL_UNSIGNED in
 981            all decls
 982
 983    asm_written_flag:
 984
 985        TREE_ASM_WRITTEN in
 986            VAR_DECL, FUNCTION_DECL, TYPE_DECL
 987            RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE
 988            BLOCK, STRING_CST
 989
 990        SSA_NAME_OCCURS_IN_ABNORMAL_PHI in
 991            SSA_NAME
 992
 993    used_flag:
 994
 995        TREE_USED in
 996            all expressions
 997            all decls
 998            IDENTIFIER_NODE
 999
1000    nothrow_flag:
1001
1002        TREE_NOTHROW in
1003            CALL_EXPR
1004            FUNCTION_DECL
1005
1006        TYPE_ALIGN_OK in
1007            all types
1008
1009        TREE_THIS_NOTRAP in
1010           INDIRECT_REF, MEM_REF, TARGET_MEM_REF, ARRAY_REF, ARRAY_RANGE_REF
1011
1012        SSA_NAME_IN_FREELIST in
1013           SSA_NAME
1014
1015        VAR_DECL_NONALIASED in
1016           VAR_DECL
1017
1018    deprecated_flag:
1019
1020        TREE_DEPRECATED in
1021            all decls
1022            all types
1023
1024        IDENTIFIER_TRANSPARENT_ALIAS in
1025            IDENTIFIER_NODE
1026
1027    visited:
1028
1029        TREE_VISITED in
1030            all trees (used liberally by many passes)
1031
1032    saturating_flag:
1033
1034        TYPE_SATURATING in
1035            all types
1036
1037        VAR_DECL_IS_VIRTUAL_OPERAND in
1038            VAR_DECL
1039
1040    nowarning_flag:
1041
1042        TREE_NO_WARNING in
1043            all expressions
1044            all decls
1045
1046        TYPE_ARTIFICIAL in
1047            all types
1048
1049    default_def_flag:
1050
1051        TYPE_VECTOR_OPAQUE in
1052            VECTOR_TYPE
1053
1054        SSA_NAME_IS_DEFAULT_DEF in
1055            SSA_NAME
1056
1057        DECL_NONLOCAL_FRAME in
1058            VAR_DECL
1059
1060        TYPE_FINAL_P in
1061            RECORD_TYPE, UNION_TYPE and QUAL_UNION_TYPE
1062 */
1063
1064 struct GTY(()) tree_typed {
1065   struct tree_base base;
1066   tree type;
1067 };
1068
1069 struct GTY(()) tree_common {
1070   struct tree_typed typed;
1071   tree chain;
1072 };
1073
1074 struct GTY(()) tree_int_cst {
1075   struct tree_typed typed;
1076   HOST_WIDE_INT val[1];
1077 };
1078
1079
1080 struct GTY(()) tree_real_cst {
1081   struct tree_typed typed;
1082   struct real_value * real_cst_ptr;
1083 };
1084
1085 struct GTY(()) tree_fixed_cst {
1086   struct tree_typed typed;
1087   struct fixed_value * fixed_cst_ptr;
1088 };
1089
1090 struct GTY(()) tree_string {
1091   struct tree_typed typed;
1092   int length;
1093   char str[1];
1094 };
1095
1096 struct GTY(()) tree_complex {
1097   struct tree_typed typed;
1098   tree real;
1099   tree imag;
1100 };
1101
1102 struct GTY(()) tree_vector {
1103   struct tree_typed typed;
1104   tree GTY ((length ("TYPE_VECTOR_SUBPARTS (TREE_TYPE ((tree)&%h))"))) elts[1];
1105 };
1106
1107 struct GTY(()) tree_identifier {
1108   struct tree_common common;
1109   struct ht_identifier id;
1110 };
1111
1112 struct GTY(()) tree_list {
1113   struct tree_common common;
1114   tree purpose;
1115   tree value;
1116 };
1117
1118 struct GTY(()) tree_vec {
1119   struct tree_common common;
1120   tree GTY ((length ("TREE_VEC_LENGTH ((tree)&%h)"))) a[1];
1121 };
1122
1123 /* A single element of a CONSTRUCTOR. VALUE holds the actual value of the
1124    element. INDEX can optionally design the position of VALUE: in arrays,
1125    it is the index where VALUE has to be placed; in structures, it is the
1126    FIELD_DECL of the member.  */
1127 struct GTY(()) constructor_elt {
1128   tree index;
1129   tree value;
1130 };
1131
1132 struct GTY(()) tree_constructor {
1133   struct tree_typed typed;
1134   vec<constructor_elt, va_gc> *elts;
1135 };
1136
1137 enum omp_clause_depend_kind
1138 {
1139   OMP_CLAUSE_DEPEND_IN,
1140   OMP_CLAUSE_DEPEND_OUT,
1141   OMP_CLAUSE_DEPEND_INOUT,
1142   OMP_CLAUSE_DEPEND_LAST
1143 };
1144
1145 enum omp_clause_map_kind
1146 {
1147   OMP_CLAUSE_MAP_ALLOC,
1148   OMP_CLAUSE_MAP_TO,
1149   OMP_CLAUSE_MAP_FROM,
1150   OMP_CLAUSE_MAP_TOFROM,
1151   /* The following kind is an internal only map kind, used for pointer based
1152      array sections.  OMP_CLAUSE_SIZE for these is not the pointer size,
1153      which is implicitly POINTER_SIZE / BITS_PER_UNIT, but the bias.  */
1154   OMP_CLAUSE_MAP_POINTER,
1155   OMP_CLAUSE_MAP_LAST
1156 };
1157
1158 enum omp_clause_proc_bind_kind
1159 {
1160   /* Numbers should match omp_proc_bind_t enum in omp.h.  */
1161   OMP_CLAUSE_PROC_BIND_FALSE = 0,
1162   OMP_CLAUSE_PROC_BIND_TRUE = 1,
1163   OMP_CLAUSE_PROC_BIND_MASTER = 2,
1164   OMP_CLAUSE_PROC_BIND_CLOSE = 3,
1165   OMP_CLAUSE_PROC_BIND_SPREAD = 4,
1166   OMP_CLAUSE_PROC_BIND_LAST
1167 };
1168
1169 struct GTY(()) tree_exp {
1170   struct tree_typed typed;
1171   location_t locus;
1172   tree GTY ((special ("tree_exp"),
1173              desc ("TREE_CODE ((tree) &%0)")))
1174     operands[1];
1175 };
1176
1177 /* Immediate use linking structure.  This structure is used for maintaining
1178    a doubly linked list of uses of an SSA_NAME.  */
1179 struct GTY(()) ssa_use_operand_t {
1180   struct ssa_use_operand_t* GTY((skip(""))) prev;
1181   struct ssa_use_operand_t* GTY((skip(""))) next;
1182   /* Immediate uses for a given SSA name are maintained as a cyclic
1183      list.  To recognize the root of this list, the location field
1184      needs to point to the original SSA name.  Since statements and
1185      SSA names are of different data types, we need this union.  See
1186      the explanation in struct imm_use_iterator.  */
1187   union { gimple stmt; tree ssa_name; } GTY((skip(""))) loc;
1188   tree *GTY((skip(""))) use;
1189 };
1190
1191 struct GTY(()) tree_ssa_name {
1192   struct tree_typed typed;
1193
1194   /* _DECL wrapped by this SSA name.  */
1195   tree var;
1196
1197   /* Statement that defines this SSA name.  */
1198   gimple def_stmt;
1199
1200   /* Value range information.  */
1201   union ssa_name_info_type {
1202     /* Pointer attributes used for alias analysis.  */
1203     struct GTY ((tag ("0"))) ptr_info_def *ptr_info;
1204     /* Value range attributes used for zero/sign extension elimination.  */
1205     struct GTY ((tag ("1"))) range_info_def *range_info;
1206   } GTY ((desc ("%1.typed.type ?" \
1207                 "!POINTER_TYPE_P (TREE_TYPE ((tree)&%1)) : 2"))) info;
1208
1209   /* Immediate uses list for this SSA_NAME.  */
1210   struct ssa_use_operand_t imm_uses;
1211 };
1212
1213 struct GTY(()) phi_arg_d {
1214   /* imm_use MUST be the first element in struct because we do some
1215      pointer arithmetic with it.  See phi_arg_index_from_use.  */
1216   struct ssa_use_operand_t imm_use;
1217   tree def;
1218   location_t locus;
1219 };
1220
1221 struct GTY(()) tree_omp_clause {
1222   struct tree_common common;
1223   location_t locus;
1224   enum omp_clause_code code;
1225   union omp_clause_subcode {
1226     enum omp_clause_default_kind   default_kind;
1227     enum omp_clause_schedule_kind  schedule_kind;
1228     enum omp_clause_depend_kind    depend_kind;
1229     enum omp_clause_map_kind       map_kind;
1230     enum omp_clause_proc_bind_kind proc_bind_kind;
1231     enum tree_code                 reduction_code;
1232   } GTY ((skip)) subcode;
1233
1234   /* The gimplification of OMP_CLAUSE_REDUCTION_{INIT,MERGE} for omp-low's
1235      usage.  */
1236   gimple_seq gimple_reduction_init;
1237   gimple_seq gimple_reduction_merge;
1238
1239   tree GTY ((length ("omp_clause_num_ops[OMP_CLAUSE_CODE ((tree)&%h)]")))
1240     ops[1];
1241 };
1242
1243 struct GTY(()) tree_block {
1244   struct tree_base base;
1245   tree chain;
1246
1247   unsigned abstract_flag : 1;
1248   unsigned block_num : 31;
1249
1250   location_t locus;
1251
1252   tree vars;
1253   vec<tree, va_gc> *nonlocalized_vars;
1254
1255   tree subblocks;
1256   tree supercontext;
1257   tree abstract_origin;
1258   tree fragment_origin;
1259   tree fragment_chain;
1260 };
1261
1262 struct GTY(()) tree_type_common {
1263   struct tree_common common;
1264   tree size;
1265   tree size_unit;
1266   tree attributes;
1267   unsigned int uid;
1268
1269   unsigned int precision : 10;
1270   unsigned no_force_blk_flag : 1;
1271   unsigned needs_constructing_flag : 1;
1272   unsigned transparent_aggr_flag : 1;
1273   unsigned restrict_flag : 1;
1274   unsigned contains_placeholder_bits : 2;
1275
1276   ENUM_BITFIELD(machine_mode) mode : 8;
1277
1278   unsigned string_flag : 1;
1279   unsigned lang_flag_0 : 1;
1280   unsigned lang_flag_1 : 1;
1281   unsigned lang_flag_2 : 1;
1282   unsigned lang_flag_3 : 1;
1283   unsigned lang_flag_4 : 1;
1284   unsigned lang_flag_5 : 1;
1285   unsigned lang_flag_6 : 1;
1286
1287   unsigned int align;
1288   alias_set_type alias_set;
1289   tree pointer_to;
1290   tree reference_to;
1291   union tree_type_symtab {
1292     int GTY ((tag ("TYPE_SYMTAB_IS_ADDRESS"))) address;
1293     const char * GTY ((tag ("TYPE_SYMTAB_IS_POINTER"))) pointer;
1294     struct die_struct * GTY ((tag ("TYPE_SYMTAB_IS_DIE"))) die;
1295   } GTY ((desc ("debug_hooks->tree_type_symtab_field"))) symtab;
1296   tree canonical;
1297   tree next_variant;
1298   tree main_variant;
1299   tree context;
1300   tree name;
1301 };
1302
1303 struct GTY(()) tree_type_with_lang_specific {
1304   struct tree_type_common common;
1305   /* Points to a structure whose details depend on the language in use.  */
1306   struct lang_type *lang_specific;
1307 };
1308
1309 struct GTY(()) tree_type_non_common {
1310   struct tree_type_with_lang_specific with_lang_specific;
1311   tree values;
1312   tree minval;
1313   tree maxval;
1314   tree binfo;
1315 };
1316
1317 struct GTY (()) tree_binfo {
1318   struct tree_common common;
1319
1320   tree offset;
1321   tree vtable;
1322   tree virtuals;
1323   tree vptr_field;
1324   vec<tree, va_gc> *base_accesses;
1325   tree inheritance;
1326
1327   tree vtt_subvtt;
1328   tree vtt_vptr;
1329
1330   vec<tree, va_gc> base_binfos;
1331 };
1332
1333 struct GTY(()) tree_decl_minimal {
1334   struct tree_common common;
1335   location_t locus;
1336   unsigned int uid;
1337   tree name;
1338   tree context;
1339 };
1340
1341 struct GTY(()) tree_decl_common {
1342   struct tree_decl_minimal common;
1343   tree size;
1344
1345   ENUM_BITFIELD(machine_mode) mode : 8;
1346
1347   unsigned nonlocal_flag : 1;
1348   unsigned virtual_flag : 1;
1349   unsigned ignored_flag : 1;
1350   unsigned abstract_flag : 1;
1351   unsigned artificial_flag : 1;
1352   unsigned preserve_flag: 1;
1353   unsigned debug_expr_is_from : 1;
1354
1355   unsigned lang_flag_0 : 1;
1356   unsigned lang_flag_1 : 1;
1357   unsigned lang_flag_2 : 1;
1358   unsigned lang_flag_3 : 1;
1359   unsigned lang_flag_4 : 1;
1360   unsigned lang_flag_5 : 1;
1361   unsigned lang_flag_6 : 1;
1362   unsigned lang_flag_7 : 1;
1363   unsigned lang_flag_8 : 1;
1364
1365   /* In VAR_DECL and PARM_DECL, this is DECL_REGISTER.  */
1366   unsigned decl_flag_0 : 1;
1367   /* In FIELD_DECL, this is DECL_BIT_FIELD
1368      In VAR_DECL and FUNCTION_DECL, this is DECL_EXTERNAL.
1369      In TYPE_DECL, this is TYPE_DECL_SUPPRESS_DEBUG.  */
1370   unsigned decl_flag_1 : 1;
1371   /* In FIELD_DECL, this is DECL_NONADDRESSABLE_P
1372      In VAR_DECL, PARM_DECL and RESULT_DECL, this is
1373      DECL_HAS_VALUE_EXPR_P.  */
1374   unsigned decl_flag_2 : 1;
1375   /* 1 bit unused.  */
1376   unsigned decl_flag_3 : 1;
1377   /* Logically, these two would go in a theoretical base shared by var and
1378      parm decl. */
1379   unsigned gimple_reg_flag : 1;
1380   /* In VAR_DECL, PARM_DECL and RESULT_DECL, this is DECL_BY_REFERENCE.  */
1381   unsigned decl_by_reference_flag : 1;
1382   /* In a VAR_DECL and PARM_DECL, this is DECL_READ_P.  */
1383   unsigned decl_read_flag : 1;
1384   /* In a VAR_DECL or RESULT_DECL, this is DECL_NONSHAREABLE.  */
1385   unsigned decl_nonshareable_flag : 1;
1386
1387   /* DECL_OFFSET_ALIGN, used only for FIELD_DECLs.  */
1388   unsigned int off_align : 8;
1389
1390   /* 24 bits unused.  */
1391
1392   /* DECL_ALIGN.  It should have the same size as TYPE_ALIGN.  */
1393   unsigned int align;
1394
1395   /* UID for points-to sets, stable over copying from inlining.  */
1396   unsigned int pt_uid;
1397
1398   tree size_unit;
1399   tree initial;
1400   tree attributes;
1401   tree abstract_origin;
1402
1403   /* Points to a structure whose details depend on the language in use.  */
1404   struct lang_decl *lang_specific;
1405 };
1406
1407 struct GTY(()) tree_decl_with_rtl {
1408   struct tree_decl_common common;
1409   rtx rtl;
1410 };
1411
1412 struct GTY(()) tree_field_decl {
1413   struct tree_decl_common common;
1414
1415   tree offset;
1416   tree bit_field_type;
1417   tree qualifier;
1418   tree bit_offset;
1419   tree fcontext;
1420 };
1421
1422 struct GTY(()) tree_label_decl {
1423   struct tree_decl_with_rtl common;
1424   int label_decl_uid;
1425   int eh_landing_pad_nr;
1426 };
1427
1428 struct GTY(()) tree_result_decl {
1429   struct tree_decl_with_rtl common;
1430 };
1431
1432 struct GTY(()) tree_const_decl {
1433   struct tree_decl_common common;
1434 };
1435
1436 struct GTY(()) tree_parm_decl {
1437   struct tree_decl_with_rtl common;
1438   rtx incoming_rtl;
1439 };
1440
1441 struct GTY(()) tree_decl_with_vis {
1442  struct tree_decl_with_rtl common;
1443  tree assembler_name;
1444  struct symtab_node *symtab_node;
1445
1446  /* Belong to VAR_DECL exclusively.  */
1447  unsigned defer_output : 1;
1448  unsigned hard_register : 1;
1449  unsigned common_flag : 1;
1450  unsigned in_text_section : 1;
1451  unsigned in_constant_pool : 1;
1452  unsigned dllimport_flag : 1;
1453  /* Don't belong to VAR_DECL exclusively.  */
1454  unsigned weak_flag : 1;
1455
1456  unsigned seen_in_bind_expr : 1;
1457  unsigned comdat_flag : 1;
1458  ENUM_BITFIELD(symbol_visibility) visibility : 2;
1459  unsigned visibility_specified : 1;
1460  /* Belongs to VAR_DECL exclusively.  */
1461  ENUM_BITFIELD(tls_model) tls_model : 3;
1462
1463  /* Belong to FUNCTION_DECL exclusively.  */
1464  unsigned init_priority_p : 1;
1465  /* Used by C++ only.  Might become a generic decl flag.  */
1466  unsigned shadowed_for_var_p : 1;
1467  /* Belong to FUNCTION_DECL exclusively.  */
1468  unsigned cxx_constructor : 1;
1469  /* Belong to FUNCTION_DECL exclusively.  */
1470  unsigned cxx_destructor : 1;
1471  /* Belong to FUNCTION_DECL exclusively.  */
1472  unsigned final : 1;
1473  /* 12 unused bits. */
1474 };
1475
1476 struct GTY(()) tree_var_decl {
1477   struct tree_decl_with_vis common;
1478 };
1479
1480 struct GTY(()) tree_decl_non_common {
1481   struct tree_decl_with_vis common;
1482   /* C++ uses this in namespaces.  */
1483   tree saved_tree;
1484   /* C++ uses this in templates.  */
1485   tree arguments;
1486   /* Almost all FE's use this.  */
1487   tree result;
1488   /* C++ uses this in namespaces and function_decls.  */
1489   tree vindex;
1490 };
1491
1492 /* FUNCTION_DECL inherits from DECL_NON_COMMON because of the use of the
1493    arguments/result/saved_tree fields by front ends.   It was either inherit
1494    FUNCTION_DECL from non_common, or inherit non_common from FUNCTION_DECL,
1495    which seemed a bit strange.  */
1496
1497 struct GTY(()) tree_function_decl {
1498   struct tree_decl_non_common common;
1499
1500   struct function *f;
1501
1502   /* The personality function. Used for stack unwinding. */
1503   tree personality;
1504
1505   /* Function specific options that are used by this function.  */
1506   tree function_specific_target;        /* target options */
1507   tree function_specific_optimization;  /* optimization options */
1508
1509   /* In a FUNCTION_DECL for which DECL_BUILT_IN holds, this is
1510      DECL_FUNCTION_CODE.  Otherwise unused.
1511      ???  The bitfield needs to be able to hold all target function
1512           codes as well.  */
1513   ENUM_BITFIELD(built_in_function) function_code : 11;
1514   ENUM_BITFIELD(built_in_class) built_in_class : 2;
1515
1516   unsigned static_ctor_flag : 1;
1517   unsigned static_dtor_flag : 1;
1518   unsigned uninlinable : 1;
1519
1520   unsigned possibly_inlined : 1;
1521   unsigned novops_flag : 1;
1522   unsigned returns_twice_flag : 1;
1523   unsigned malloc_flag : 1;
1524   unsigned operator_new_flag : 1;
1525   unsigned declared_inline_flag : 1;
1526   unsigned regdecl_flag : 1;
1527   unsigned no_inline_warning_flag : 1;
1528
1529   unsigned no_instrument_function_entry_exit : 1;
1530   unsigned no_limit_stack : 1;
1531   unsigned disregard_inline_limits : 1;
1532   unsigned pure_flag : 1;
1533   unsigned looping_const_or_pure_flag : 1;
1534   unsigned has_debug_args_flag : 1;
1535   unsigned tm_clone_flag : 1;
1536   unsigned versioned_function : 1;
1537   /* No bits left.  */
1538 };
1539
1540 struct GTY(()) tree_translation_unit_decl {
1541   struct tree_decl_common common;
1542   /* Source language of this translation unit.  Used for DWARF output.  */
1543   const char * GTY((skip(""))) language;
1544   /* TODO: Non-optimization used to build this translation unit.  */
1545   /* TODO: Root of a partial DWARF tree for global types and decls.  */
1546 };
1547
1548 struct GTY(()) tree_type_decl {
1549   struct tree_decl_non_common common;
1550
1551 };
1552
1553 struct GTY ((chain_next ("%h.next"), chain_prev ("%h.prev"))) tree_statement_list_node
1554  {
1555   struct tree_statement_list_node *prev;
1556   struct tree_statement_list_node *next;
1557   tree stmt;
1558 };
1559
1560 struct GTY(()) tree_statement_list
1561  {
1562   struct tree_typed typed;
1563   struct tree_statement_list_node *head;
1564   struct tree_statement_list_node *tail;
1565 };
1566
1567
1568 /* Optimization options used by a function.  */
1569
1570 struct GTY(()) tree_optimization_option {
1571   struct tree_common common;
1572
1573   /* The optimization options used by the user.  */
1574   struct cl_optimization opts;
1575
1576   /* Target optabs for this set of optimization options.  This is of
1577      type `struct target_optabs *'.  */
1578   void *GTY ((atomic)) optabs;
1579
1580   /* The value of this_target_optabs against which the optabs above were
1581      generated.  */
1582   struct target_optabs *GTY ((skip)) base_optabs;
1583 };
1584
1585 /* Forward declaration, defined in target-globals.h.  */
1586
1587 struct GTY(()) target_globals;
1588
1589 /* Target options used by a function.  */
1590
1591 struct GTY(()) tree_target_option {
1592   struct tree_common common;
1593
1594   /* Target globals for the corresponding target option.  */
1595   struct target_globals *globals;
1596
1597   /* The optimization options used by the user.  */
1598   struct cl_target_option opts;
1599 };
1600
1601 /* Define the overall contents of a tree node.
1602    It may be any of the structures declared above
1603    for various types of node.  */
1604 union GTY ((ptr_alias (union lang_tree_node),
1605             desc ("tree_node_structure (&%h)"), variable_size)) tree_node {
1606   struct tree_base GTY ((tag ("TS_BASE"))) base;
1607   struct tree_typed GTY ((tag ("TS_TYPED"))) typed;
1608   struct tree_common GTY ((tag ("TS_COMMON"))) common;
1609   struct tree_int_cst GTY ((tag ("TS_INT_CST"))) int_cst;
1610   struct tree_real_cst GTY ((tag ("TS_REAL_CST"))) real_cst;
1611   struct tree_fixed_cst GTY ((tag ("TS_FIXED_CST"))) fixed_cst;
1612   struct tree_vector GTY ((tag ("TS_VECTOR"))) vector;
1613   struct tree_string GTY ((tag ("TS_STRING"))) string;
1614   struct tree_complex GTY ((tag ("TS_COMPLEX"))) complex;
1615   struct tree_identifier GTY ((tag ("TS_IDENTIFIER"))) identifier;
1616   struct tree_decl_minimal GTY((tag ("TS_DECL_MINIMAL"))) decl_minimal;
1617   struct tree_decl_common GTY ((tag ("TS_DECL_COMMON"))) decl_common;
1618   struct tree_decl_with_rtl GTY ((tag ("TS_DECL_WRTL"))) decl_with_rtl;
1619   struct tree_decl_non_common  GTY ((tag ("TS_DECL_NON_COMMON")))
1620     decl_non_common;
1621   struct tree_parm_decl  GTY  ((tag ("TS_PARM_DECL"))) parm_decl;
1622   struct tree_decl_with_vis GTY ((tag ("TS_DECL_WITH_VIS"))) decl_with_vis;
1623   struct tree_var_decl GTY ((tag ("TS_VAR_DECL"))) var_decl;
1624   struct tree_field_decl GTY ((tag ("TS_FIELD_DECL"))) field_decl;
1625   struct tree_label_decl GTY ((tag ("TS_LABEL_DECL"))) label_decl;
1626   struct tree_result_decl GTY ((tag ("TS_RESULT_DECL"))) result_decl;
1627   struct tree_const_decl GTY ((tag ("TS_CONST_DECL"))) const_decl;
1628   struct tree_type_decl GTY ((tag ("TS_TYPE_DECL"))) type_decl;
1629   struct tree_function_decl GTY ((tag ("TS_FUNCTION_DECL"))) function_decl;
1630   struct tree_translation_unit_decl GTY ((tag ("TS_TRANSLATION_UNIT_DECL")))
1631     translation_unit_decl;
1632   struct tree_type_common GTY ((tag ("TS_TYPE_COMMON"))) type_common;
1633   struct tree_type_with_lang_specific GTY ((tag ("TS_TYPE_WITH_LANG_SPECIFIC")))
1634     type_with_lang_specific;
1635   struct tree_type_non_common GTY ((tag ("TS_TYPE_NON_COMMON")))
1636     type_non_common;
1637   struct tree_list GTY ((tag ("TS_LIST"))) list;
1638   struct tree_vec GTY ((tag ("TS_VEC"))) vec;
1639   struct tree_exp GTY ((tag ("TS_EXP"))) exp;
1640   struct tree_ssa_name GTY ((tag ("TS_SSA_NAME"))) ssa_name;
1641   struct tree_block GTY ((tag ("TS_BLOCK"))) block;
1642   struct tree_binfo GTY ((tag ("TS_BINFO"))) binfo;
1643   struct tree_statement_list GTY ((tag ("TS_STATEMENT_LIST"))) stmt_list;
1644   struct tree_constructor GTY ((tag ("TS_CONSTRUCTOR"))) constructor;
1645   struct tree_omp_clause GTY ((tag ("TS_OMP_CLAUSE"))) omp_clause;
1646   struct tree_optimization_option GTY ((tag ("TS_OPTIMIZATION"))) optimization;
1647   struct tree_target_option GTY ((tag ("TS_TARGET_OPTION"))) target_option;
1648 };
1649
1650 /* Structure describing an attribute and a function to handle it.  */
1651 struct attribute_spec {
1652   /* The name of the attribute (without any leading or trailing __),
1653      or NULL to mark the end of a table of attributes.  */
1654   const char *name;
1655   /* The minimum length of the list of arguments of the attribute.  */
1656   int min_length;
1657   /* The maximum length of the list of arguments of the attribute
1658      (-1 for no maximum).  */
1659   int max_length;
1660   /* Whether this attribute requires a DECL.  If it does, it will be passed
1661      from types of DECLs, function return types and array element types to
1662      the DECLs, function types and array types respectively; but when
1663      applied to a type in any other circumstances, it will be ignored with
1664      a warning.  (If greater control is desired for a given attribute,
1665      this should be false, and the flags argument to the handler may be
1666      used to gain greater control in that case.)  */
1667   bool decl_required;
1668   /* Whether this attribute requires a type.  If it does, it will be passed
1669      from a DECL to the type of that DECL.  */
1670   bool type_required;
1671   /* Whether this attribute requires a function (or method) type.  If it does,
1672      it will be passed from a function pointer type to the target type,
1673      and from a function return type (which is not itself a function
1674      pointer type) to the function type.  */
1675   bool function_type_required;
1676   /* Function to handle this attribute.  NODE points to the node to which
1677      the attribute is to be applied.  If a DECL, it should be modified in
1678      place; if a TYPE, a copy should be created.  NAME is the name of the
1679      attribute (possibly with leading or trailing __).  ARGS is the TREE_LIST
1680      of the arguments (which may be NULL).  FLAGS gives further information
1681      about the context of the attribute.  Afterwards, the attributes will
1682      be added to the DECL_ATTRIBUTES or TYPE_ATTRIBUTES, as appropriate,
1683      unless *NO_ADD_ATTRS is set to true (which should be done on error,
1684      as well as in any other cases when the attributes should not be added
1685      to the DECL or TYPE).  Depending on FLAGS, any attributes to be
1686      applied to another type or DECL later may be returned;
1687      otherwise the return value should be NULL_TREE.  This pointer may be
1688      NULL if no special handling is required beyond the checks implied
1689      by the rest of this structure.  */
1690   tree (*handler) (tree *node, tree name, tree args,
1691                    int flags, bool *no_add_attrs);
1692   /* Specifies if attribute affects type's identity.  */
1693   bool affects_type_identity;
1694 };
1695
1696 /* These functions allow a front-end to perform a manual layout of a
1697    RECORD_TYPE.  (For instance, if the placement of subsequent fields
1698    depends on the placement of fields so far.)  Begin by calling
1699    start_record_layout.  Then, call place_field for each of the
1700    fields.  Then, call finish_record_layout.  See layout_type for the
1701    default way in which these functions are used.  */
1702 typedef struct record_layout_info_s {
1703   /* The RECORD_TYPE that we are laying out.  */
1704   tree t;
1705   /* The offset into the record so far, in bytes, not including bits in
1706      BITPOS.  */
1707   tree offset;
1708   /* The last known alignment of SIZE.  */
1709   unsigned int offset_align;
1710   /* The bit position within the last OFFSET_ALIGN bits, in bits.  */
1711   tree bitpos;
1712   /* The alignment of the record so far, in bits.  */
1713   unsigned int record_align;
1714   /* The alignment of the record so far, ignoring #pragma pack and
1715      __attribute__ ((packed)), in bits.  */
1716   unsigned int unpacked_align;
1717   /* The previous field laid out.  */
1718   tree prev_field;
1719   /* The static variables (i.e., class variables, as opposed to
1720      instance variables) encountered in T.  */
1721   vec<tree, va_gc> *pending_statics;
1722   /* Bits remaining in the current alignment group */
1723   int remaining_in_alignment;
1724   /* True if we've seen a packed field that didn't have normal
1725      alignment anyway.  */
1726   int packed_maybe_necessary;
1727 } *record_layout_info;
1728
1729 /* Iterator for going through the function arguments.  */
1730 struct function_args_iterator {
1731   tree next;                    /* TREE_LIST pointing to the next argument */
1732 };
1733
1734 /* Structures to map from a tree to another tree.  */
1735 struct GTY(()) tree_map_base {
1736   tree from;
1737 };
1738
1739 /* Map from a tree to another tree.  */
1740
1741 struct GTY(()) tree_map {
1742   struct tree_map_base base;
1743   unsigned int hash;
1744   tree to;
1745 };
1746
1747 /* Map from a decl tree to another tree.  */
1748 struct GTY(()) tree_decl_map {
1749   struct tree_map_base base;
1750   tree to;
1751 };
1752
1753 /* Map from a tree to an int.  */
1754 struct GTY(()) tree_int_map {
1755   struct tree_map_base base;
1756   unsigned int to;
1757 };
1758
1759 /* Map from a tree to initialization/finalization priorities.  */
1760 struct GTY(()) tree_priority_map {
1761   struct tree_map_base base;
1762   priority_type init;
1763   priority_type fini;
1764 };
1765
1766 /* Map from a decl tree to a tree vector.  */
1767 struct GTY(()) tree_vec_map {
1768   struct tree_map_base base;
1769   vec<tree, va_gc> *to;
1770 };
1771
1772 /* Abstract iterators for CALL_EXPRs.  These static inline definitions
1773    have to go towards the end of tree.h so that union tree_node is fully
1774    defined by this point.  */
1775
1776 /* Structure containing iterator state.  */
1777 struct call_expr_arg_iterator {
1778   tree t;       /* the call_expr */
1779   int n;        /* argument count */
1780   int i;        /* next argument index */
1781 };
1782
1783 struct const_call_expr_arg_iterator {
1784   const_tree t; /* the call_expr */
1785   int n;        /* argument count */
1786   int i;        /* next argument index */
1787 };
1788
1789 /* The builtin_info structure holds the FUNCTION_DECL of the standard builtin
1790    function, and a flag that says if the function is available implicitly, or
1791    whether the user has to code explicit calls to __builtin_<xxx>.  */
1792 struct GTY(()) builtin_info_type {
1793   tree decl[(int)END_BUILTINS];
1794   bool implicit_p[(int)END_BUILTINS];
1795 };
1796
1797
1798 /*---------------------------------------------------------------------------
1799                                 Global variables
1800 ---------------------------------------------------------------------------*/
1801 /* Matrix describing the structures contained in a given tree code.  */
1802 extern unsigned char tree_contains_struct[MAX_TREE_CODES][64];
1803
1804 /* Class of tree given its code.  */
1805 extern const enum tree_code_class tree_code_type[];
1806
1807 /* Each tree code class has an associated string representation.
1808    These must correspond to the tree_code_class entries.  */
1809 extern const char *const tree_code_class_strings[];
1810
1811 /* Number of argument-words in each kind of tree-node.  */
1812 extern const unsigned char tree_code_length[];
1813
1814 /* Vector of all alias pairs for global symbols.  */
1815 extern GTY(()) vec<alias_pair, va_gc> *alias_pairs;
1816
1817 /* Names of all the built_in classes.  */
1818 extern const char *const built_in_class_names[BUILT_IN_LAST];
1819
1820 /* Names of all the built_in functions.  */
1821 extern const char * built_in_names[(int) END_BUILTINS];
1822
1823 /* Number of operands and names for each OMP_CLAUSE node.  */
1824 extern unsigned const char omp_clause_num_ops[];
1825 extern const char * const omp_clause_code_name[];
1826
1827 /* A vector of all translation-units.  */
1828 extern GTY (()) vec<tree, va_gc> *all_translation_units;
1829
1830 /* Vector of standard trees used by the C compiler.  */
1831 extern GTY(()) tree global_trees[TI_MAX];
1832
1833 /* The standard C integer types.  Use integer_type_kind to index into
1834    this array.  */
1835 extern GTY(()) tree integer_types[itk_none];
1836
1837 /* Types used to represent sizes.  */
1838 extern GTY(()) tree sizetype_tab[(int) stk_type_kind_last];
1839
1840 /* Arrays for keeping track of tree node statistics.  */
1841 extern int tree_node_counts[];
1842 extern int tree_node_sizes[];
1843
1844 /* True if we are in gimple form and the actions of the folders need to
1845    be restricted.  False if we are not in gimple form and folding is not
1846    restricted to creating gimple expressions.  */
1847 extern bool in_gimple_form;
1848
1849 /* Functional interface to the builtin functions.  */
1850 extern GTY(()) builtin_info_type builtin_info;
1851
1852 /* If nonzero, an upper limit on alignment of structure fields, in bits,  */
1853 extern unsigned int maximum_field_alignment;
1854
1855 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
1856    Zero means allow extended lvalues.  */
1857 extern int pedantic_lvalues;
1858
1859 /* Points to the FUNCTION_DECL of the function whose body we are reading.  */
1860 extern GTY(()) tree current_function_decl;
1861
1862 /* Nonzero means a FUNC_BEGIN label was emitted.  */
1863 extern GTY(()) const char * current_function_func_begin_label;
1864
1865 #endif  // GCC_TREE_CORE_H