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      1 /* Core data structures for the 'tree' type.
      2    Copyright (C) 1989-2024 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 "symtab.h"
     24 
     25 /* This file contains all the data structures that define the 'tree' type.
     26    There are no accessor macros nor functions in this file. Only the
     27    basic data structures, extern declarations and type definitions.  */
     28 
     29 /*---------------------------------------------------------------------------
     30    Forward type declarations.  Mostly to avoid including unnecessary headers
     31 ---------------------------------------------------------------------------*/
     32 struct function;
     33 struct real_value;
     34 struct fixed_value;
     35 struct ptr_info_def;
     36 struct die_struct;
     37 
     38 
     39 /*---------------------------------------------------------------------------
     40                               #defined constants
     41 ---------------------------------------------------------------------------*/
     42 /* Nonzero if this is a call to a function whose return value depends
     43    solely on its arguments, has no side effects, and does not read
     44    global memory.  This corresponds to TREE_READONLY for function
     45    decls.  */
     46 #define ECF_CONST		  (1 << 0)
     47 
     48 /* Nonzero if this is a call to "pure" function (like const function,
     49    but may read memory.  This corresponds to DECL_PURE_P for function
     50    decls.  */
     51 #define ECF_PURE		  (1 << 1)
     52 
     53 /* Nonzero if this is ECF_CONST or ECF_PURE but cannot be proven to no
     54    infinite loop.  This corresponds to DECL_LOOPING_CONST_OR_PURE_P
     55    for function decls.*/
     56 #define ECF_LOOPING_CONST_OR_PURE (1 << 2)
     57 
     58 /* Nonzero if this call will never return.  */
     59 #define ECF_NORETURN		  (1 << 3)
     60 
     61 /* Nonzero if this is a call to malloc or a related function.  */
     62 #define ECF_MALLOC		  (1 << 4)
     63 
     64 /* Nonzero if it is plausible that this is a call to alloca.  */
     65 #define ECF_MAY_BE_ALLOCA	  (1 << 5)
     66 
     67 /* Nonzero if this is a call to a function that won't throw an exception.  */
     68 #define ECF_NOTHROW		  (1 << 6)
     69 
     70 /* Nonzero if this is a call to setjmp or a related function.  */
     71 #define ECF_RETURNS_TWICE	  (1 << 7)
     72 
     73 /* Nonzero if this call replaces the current stack frame.  */
     74 #define ECF_SIBCALL		  (1 << 8)
     75 
     76 /* Function does not read or write memory (but may have side effects, so
     77    it does not necessarily fit ECF_CONST).  */
     78 #define ECF_NOVOPS		  (1 << 9)
     79 
     80 /* The function does not lead to calls within current function unit.  */
     81 #define ECF_LEAF		  (1 << 10)
     82 
     83 /* Nonzero if this call returns its first argument.  */
     84 #define ECF_RET1		  (1 << 11)
     85 
     86 /* Nonzero if this call does not affect transactions.  */
     87 #define ECF_TM_PURE		  (1 << 12)
     88 
     89 /* Nonzero if this call is into the transaction runtime library.  */
     90 #define ECF_TM_BUILTIN		  (1 << 13)
     91 
     92 /* Nonzero if this is an indirect call by descriptor.  */
     93 #define ECF_BY_DESCRIPTOR	  (1 << 14)
     94 
     95 /* Nonzero if this is a cold function.  */
     96 #define ECF_COLD		  (1 << 15)
     97 
     98 /* Nonzero if this is a function expected to end with an exception.  */
     99 #define ECF_XTHROW		  (1 << 16)
    100 
    101 /* Call argument flags.  */
    102 
    103 /* Nonzero if the argument is not used by the function.  */
    104 #define EAF_UNUSED		(1 << 1)
    105 
    106 /* Following flags come in pairs.  First one is about direct dereferences
    107    from the parameter, while the second is about memory reachable by
    108    recursive dereferences.  */
    109 
    110 /* Nonzero if memory reached by the argument is not clobbered.  */
    111 #define EAF_NO_DIRECT_CLOBBER	(1 << 2)
    112 #define EAF_NO_INDIRECT_CLOBBER	(1 << 3)
    113 
    114 /* Nonzero if the argument does not escape.  */
    115 #define EAF_NO_DIRECT_ESCAPE	(1 << 4)
    116 #define EAF_NO_INDIRECT_ESCAPE	(1 << 5)
    117 
    118 /* Nonzero if the argument does not escape to return value.  */
    119 #define EAF_NOT_RETURNED_DIRECTLY (1 << 6)
    120 #define EAF_NOT_RETURNED_INDIRECTLY (1 << 7)
    121 
    122 /* Nonzero if the argument is not read.  */
    123 #define EAF_NO_DIRECT_READ	(1 << 8)
    124 #define EAF_NO_INDIRECT_READ	(1 << 9)
    125 
    126 /* Call return flags.  */
    127 /* Mask for the argument number that is returned.  Lower two bits of
    128    the return flags, encodes argument slots zero to three.  */
    129 #define ERF_RETURN_ARG_MASK	(3)
    130 
    131 /* Nonzero if the return value is equal to the argument number
    132    flags & ERF_RETURN_ARG_MASK.  */
    133 #define ERF_RETURNS_ARG		(1 << 2)
    134 
    135 /* Nonzero if the return value does not alias with anything.  Functions
    136    with the malloc attribute have this set on their return value.  */
    137 #define ERF_NOALIAS		(1 << 3)
    138 
    139 
    140 /*---------------------------------------------------------------------------
    141                                   Enumerations
    142 ---------------------------------------------------------------------------*/
    143 /* Codes of tree nodes.  */
    144 #define DEFTREECODE(SYM, STRING, TYPE, NARGS)   SYM,
    145 #define END_OF_BASE_TREE_CODES LAST_AND_UNUSED_TREE_CODE,
    146 
    147 enum tree_code {
    148 #include "all-tree.def"
    149 MAX_TREE_CODES
    150 };
    151 
    152 #undef DEFTREECODE
    153 #undef END_OF_BASE_TREE_CODES
    154 
    155 /* Number of language-independent tree codes.  */
    156 #define NUM_TREE_CODES \
    157   ((int) LAST_AND_UNUSED_TREE_CODE)
    158 
    159 #define CODE_CONTAINS_STRUCT(CODE, STRUCT) \
    160   (tree_contains_struct[(CODE)][(STRUCT)])
    161 
    162 
    163 /* Classify which part of the compiler has defined a given builtin function.
    164    Note that we assume below that this is no more than two bits.  */
    165 enum built_in_class {
    166   NOT_BUILT_IN = 0,
    167   BUILT_IN_FRONTEND,
    168   BUILT_IN_MD,
    169   BUILT_IN_NORMAL
    170 };
    171 
    172 /* Last marker used for LTO stremaing of built_in_class.  We cannot add it
    173    to the enum since we need the enumb to fit in 2 bits.  */
    174 #define BUILT_IN_LAST (BUILT_IN_NORMAL + 1)
    175 
    176 /* Codes that identify the various built in functions
    177    so that expand_call can identify them quickly.  */
    178 #define DEF_BUILTIN(ENUM, N, C, T, LT, B, F, NA, AT, IM, COND) ENUM,
    179 enum built_in_function {
    180 #include "builtins.def"
    181   /* Complex division routines in libgcc.  These are done via builtins
    182      because emit_library_call_value can't handle complex values.  */
    183   BUILT_IN_COMPLEX_MUL_MIN,
    184   BUILT_IN_COMPLEX_MUL_MAX
    185     = BUILT_IN_COMPLEX_MUL_MIN
    186       + MAX_MODE_COMPLEX_FLOAT
    187       - MIN_MODE_COMPLEX_FLOAT,
    188 
    189   BUILT_IN_COMPLEX_DIV_MIN,
    190   BUILT_IN_COMPLEX_DIV_MAX
    191     = BUILT_IN_COMPLEX_DIV_MIN
    192       + MAX_MODE_COMPLEX_FLOAT
    193       - MIN_MODE_COMPLEX_FLOAT,
    194 
    195   /* Upper bound on non-language-specific builtins.  */
    196   END_BUILTINS
    197 };
    198 
    199 /* Internal functions.  */
    200 enum internal_fn {
    201 #define DEF_INTERNAL_FN(CODE, FLAGS, FNSPEC) IFN_##CODE,
    202 #include "internal-fn.def"
    203   IFN_LAST
    204 };
    205 
    206 /* An enum that combines target-independent built-in functions with
    207    internal functions, so that they can be treated in a similar way.
    208    The numbers for built-in functions are the same as for the
    209    built_in_function enum.  The numbers for internal functions
    210    start at END_BUITLINS.  */
    211 enum combined_fn {
    212 #define DEF_BUILTIN(ENUM, N, C, T, LT, B, F, NA, AT, IM, COND) \
    213   CFN_##ENUM = int (ENUM),
    214 #include "builtins.def"
    215 
    216 
    217 #define DEF_INTERNAL_FN(CODE, FLAGS, FNSPEC) \
    218   CFN_##CODE = int (END_BUILTINS) + int (IFN_##CODE),
    219 #include "internal-fn.def"
    220 
    221   CFN_LAST
    222 };
    223 
    224 /* Tree code classes.  Each tree_code has an associated code class
    225    represented by a TREE_CODE_CLASS.  */
    226 enum tree_code_class {
    227   tcc_exceptional, /* An exceptional code (fits no category).  */
    228   tcc_constant,    /* A constant.  */
    229   /* Order of tcc_type and tcc_declaration is important.  */
    230   tcc_type,        /* A type object code.  */
    231   tcc_declaration, /* A declaration (also serving as variable refs).  */
    232   tcc_reference,   /* A reference to storage.  */
    233   tcc_comparison,  /* A comparison expression.  */
    234   tcc_unary,       /* A unary arithmetic expression.  */
    235   tcc_binary,      /* A binary arithmetic expression.  */
    236   tcc_statement,   /* A statement expression, which have side effects
    237 		      but usually no interesting value.  */
    238   tcc_vl_exp,      /* A function call or other expression with a
    239 		      variable-length operand vector.  */
    240   tcc_expression   /* Any other expression.  */
    241 };
    242 
    243 /* OMP_CLAUSE codes.  Do not reorder, as this is used to index into
    244    the tables omp_clause_num_ops and omp_clause_code_name.  */
    245 enum omp_clause_code {
    246   /* Clause zero is special-cased inside the parser
    247      (c_parser_omp_variable_list).  */
    248   OMP_CLAUSE_ERROR = 0,
    249 
    250   /* OpenACC/OpenMP clause: private (variable_list).  */
    251   OMP_CLAUSE_PRIVATE,
    252 
    253   /* OpenMP clause: shared (variable_list).  */
    254   OMP_CLAUSE_SHARED,
    255 
    256   /* OpenACC/OpenMP clause: firstprivate (variable_list).  */
    257   OMP_CLAUSE_FIRSTPRIVATE,
    258 
    259   /* OpenMP clause: lastprivate (variable_list).  */
    260   OMP_CLAUSE_LASTPRIVATE,
    261 
    262   /* OpenACC/OpenMP clause: reduction (operator:variable_list).
    263      OMP_CLAUSE_REDUCTION_CODE: The tree_code of the operator.
    264      Operand 1: OMP_CLAUSE_REDUCTION_INIT: Stmt-list to initialize the var.
    265      Operand 2: OMP_CLAUSE_REDUCTION_MERGE: Stmt-list to merge private var
    266                 into the shared one.
    267      Operand 3: OMP_CLAUSE_REDUCTION_PLACEHOLDER: A dummy VAR_DECL
    268                 placeholder used in OMP_CLAUSE_REDUCTION_{INIT,MERGE}.
    269      Operand 4: OMP_CLAUSE_REDUCTION_DECL_PLACEHOLDER: Another dummy
    270 		VAR_DECL placeholder, used like the above for C/C++ array
    271 		reductions.  */
    272   OMP_CLAUSE_REDUCTION,
    273 
    274   /* OpenMP clause: task_reduction (operator:variable_list).  */
    275   OMP_CLAUSE_TASK_REDUCTION,
    276 
    277   /* OpenMP clause: in_reduction (operator:variable_list).  */
    278   OMP_CLAUSE_IN_REDUCTION,
    279 
    280   /* OpenMP clause: copyin (variable_list).  */
    281   OMP_CLAUSE_COPYIN,
    282 
    283   /* OpenMP clause: copyprivate (variable_list).  */
    284   OMP_CLAUSE_COPYPRIVATE,
    285 
    286   /* OpenMP clause: linear (variable-list[:linear-step]).  */
    287   OMP_CLAUSE_LINEAR,
    288 
    289   /* OpenMP clause: affinity([depend-modifier :] variable-list).  */
    290   OMP_CLAUSE_AFFINITY,
    291 
    292   /* OpenMP clause: aligned (variable-list[:alignment]).  */
    293   OMP_CLAUSE_ALIGNED,
    294 
    295   /* OpenMP clause: allocate ([allocator:]variable-list).  */
    296   OMP_CLAUSE_ALLOCATE,
    297 
    298   /* OpenMP clause: depend ({in,out,inout}:variable-list).  */
    299   OMP_CLAUSE_DEPEND,
    300 
    301   /* OpenMP clause: nontemporal (variable-list).  */
    302   OMP_CLAUSE_NONTEMPORAL,
    303 
    304   /* OpenMP clause: uniform (argument-list).  */
    305   OMP_CLAUSE_UNIFORM,
    306 
    307   /* OpenMP clause: enter (extended-list).
    308      to is a deprecated alias when it appears in declare target.  */
    309   OMP_CLAUSE_ENTER,
    310 
    311   /* OpenMP clause: link (variable-list).  */
    312   OMP_CLAUSE_LINK,
    313 
    314   /* OpenMP clause: detach (event-handle).  */
    315   OMP_CLAUSE_DETACH,
    316 
    317   /* OpenACC clause: use_device (variable-list).
    318      OpenMP clause: use_device_ptr (ptr-list).  */
    319   OMP_CLAUSE_USE_DEVICE_PTR,
    320 
    321   /* OpenMP clause: use_device_addr (variable-list).  */
    322   OMP_CLAUSE_USE_DEVICE_ADDR,
    323 
    324   /* OpenMP clause: is_device_ptr (variable-list).  */
    325   OMP_CLAUSE_IS_DEVICE_PTR,
    326 
    327   /* OpenMP clause: inclusive (variable-list).  */
    328   OMP_CLAUSE_INCLUSIVE,
    329 
    330   /* OpenMP clause: exclusive (variable-list).  */
    331   OMP_CLAUSE_EXCLUSIVE,
    332 
    333   /* OpenMP clause: from (variable-list).  */
    334   OMP_CLAUSE_FROM,
    335 
    336   /* OpenMP clause: to (variable-list).  */
    337   OMP_CLAUSE_TO,
    338 
    339   /* OpenACC clauses: {copy, copyin, copyout, create, delete, deviceptr,
    340      device, host (self), present, present_or_copy (pcopy), present_or_copyin
    341      (pcopyin), present_or_copyout (pcopyout), present_or_create (pcreate)}
    342      (variable-list).
    343 
    344      OpenMP clause: map ({alloc:,to:,from:,tofrom:,}variable-list).  */
    345   OMP_CLAUSE_MAP,
    346 
    347   /* OpenMP clause: has_device_addr (variable-list).  */
    348   OMP_CLAUSE_HAS_DEVICE_ADDR,
    349 
    350   /* OpenMP clause: doacross ({source,sink}:vec).  */
    351   OMP_CLAUSE_DOACROSS,
    352 
    353   /* Internal structure to hold OpenACC cache directive's variable-list.
    354      #pragma acc cache (variable-list).  */
    355   OMP_CLAUSE__CACHE_,
    356 
    357   /* OpenACC clause: gang [(gang-argument-list)].
    358      Where
    359       gang-argument-list: [gang-argument-list, ] gang-argument
    360       gang-argument: [num:] integer-expression
    361                    | static: size-expression
    362       size-expression: * | integer-expression.  */
    363   OMP_CLAUSE_GANG,
    364 
    365   /* OpenACC clause: async [(integer-expression)].  */
    366   OMP_CLAUSE_ASYNC,
    367 
    368   /* OpenACC clause: wait [(integer-expression-list)].  */
    369   OMP_CLAUSE_WAIT,
    370 
    371   /* OpenACC clause: auto.  */
    372   OMP_CLAUSE_AUTO,
    373 
    374   /* OpenACC clause: seq.  */
    375   OMP_CLAUSE_SEQ,
    376 
    377   /* Internal clause: temporary for combined loops expansion.  */
    378   OMP_CLAUSE__LOOPTEMP_,
    379 
    380   /* Internal clause: temporary for task reductions.  */
    381   OMP_CLAUSE__REDUCTEMP_,
    382 
    383   /* Internal clause: temporary for lastprivate(conditional:).  */
    384   OMP_CLAUSE__CONDTEMP_,
    385 
    386   /* Internal clause: temporary for inscan reductions.  */
    387   OMP_CLAUSE__SCANTEMP_,
    388 
    389   /* OpenACC/OpenMP clause: if (scalar-expression).  */
    390   OMP_CLAUSE_IF,
    391 
    392   /* OpenACC clause: self.  */
    393   OMP_CLAUSE_SELF,
    394 
    395   /* OpenMP clause: num_threads (integer-expression).  */
    396   OMP_CLAUSE_NUM_THREADS,
    397 
    398   /* OpenMP clause: schedule.  */
    399   OMP_CLAUSE_SCHEDULE,
    400 
    401   /* OpenMP clause: nowait.  */
    402   OMP_CLAUSE_NOWAIT,
    403 
    404   /* OpenMP clause: ordered [(constant-integer-expression)].  */
    405   OMP_CLAUSE_ORDERED,
    406 
    407   /* OpenACC/OpenMP clause: default.  */
    408   OMP_CLAUSE_DEFAULT,
    409 
    410   /* OpenACC/OpenMP clause: collapse (constant-integer-expression).  */
    411   OMP_CLAUSE_COLLAPSE,
    412 
    413   /* OpenMP clause: untied.  */
    414   OMP_CLAUSE_UNTIED,
    415 
    416   /* OpenMP clause: final (scalar-expression).  */
    417   OMP_CLAUSE_FINAL,
    418 
    419   /* OpenMP clause: mergeable.  */
    420   OMP_CLAUSE_MERGEABLE,
    421 
    422   /* OpenMP clause: device (integer-expression).  */
    423   OMP_CLAUSE_DEVICE,
    424 
    425   /* OpenMP clause: dist_schedule (static[:chunk-size]).  */
    426   OMP_CLAUSE_DIST_SCHEDULE,
    427 
    428   /* OpenMP clause: inbranch.  */
    429   OMP_CLAUSE_INBRANCH,
    430 
    431   /* OpenMP clause: notinbranch.  */
    432   OMP_CLAUSE_NOTINBRANCH,
    433 
    434   /* OpenMP clause: num_teams(integer-expression).  */
    435   OMP_CLAUSE_NUM_TEAMS,
    436 
    437   /* OpenMP clause: thread_limit(integer-expression).  */
    438   OMP_CLAUSE_THREAD_LIMIT,
    439 
    440   /* OpenMP clause: proc_bind ({master,close,spread}).  */
    441   OMP_CLAUSE_PROC_BIND,
    442 
    443   /* OpenMP clause: safelen (constant-integer-expression).  */
    444   OMP_CLAUSE_SAFELEN,
    445 
    446   /* OpenMP clause: simdlen (constant-integer-expression).  */
    447   OMP_CLAUSE_SIMDLEN,
    448 
    449   /* OpenMP clause: device_type ({host,nohost,any}).  */
    450   OMP_CLAUSE_DEVICE_TYPE,
    451 
    452   /* OpenMP clause: for.  */
    453   OMP_CLAUSE_FOR,
    454 
    455   /* OpenMP clause: parallel.  */
    456   OMP_CLAUSE_PARALLEL,
    457 
    458   /* OpenMP clause: sections.  */
    459   OMP_CLAUSE_SECTIONS,
    460 
    461   /* OpenMP clause: taskgroup.  */
    462   OMP_CLAUSE_TASKGROUP,
    463 
    464   /* OpenMP clause: priority (integer-expression).  */
    465   OMP_CLAUSE_PRIORITY,
    466 
    467   /* OpenMP clause: grainsize (integer-expression).  */
    468   OMP_CLAUSE_GRAINSIZE,
    469 
    470   /* OpenMP clause: num_tasks (integer-expression).  */
    471   OMP_CLAUSE_NUM_TASKS,
    472 
    473   /* OpenMP clause: nogroup.  */
    474   OMP_CLAUSE_NOGROUP,
    475 
    476   /* OpenMP clause: threads.  */
    477   OMP_CLAUSE_THREADS,
    478 
    479   /* OpenMP clause: simd.  */
    480   OMP_CLAUSE_SIMD,
    481 
    482   /* OpenMP clause: hint (integer-expression).  */
    483   OMP_CLAUSE_HINT,
    484 
    485   /* OpenMP clause: defaultmap (tofrom: scalar).  */
    486   OMP_CLAUSE_DEFAULTMAP,
    487 
    488   /* OpenMP clause: order (concurrent).  */
    489   OMP_CLAUSE_ORDER,
    490 
    491   /* OpenMP clause: bind (binding).  */
    492   OMP_CLAUSE_BIND,
    493 
    494   /* OpenMP clause: filter (integer-expression).  */
    495   OMP_CLAUSE_FILTER,
    496 
    497   /* OpenMP clause: indirect [(constant-integer-expression)].  */
    498   OMP_CLAUSE_INDIRECT,
    499 
    500   /* Internally used only clause, holding SIMD uid.  */
    501   OMP_CLAUSE__SIMDUID_,
    502 
    503   /* Internally used only clause, flag whether this is SIMT simd
    504      loop or not.  */
    505   OMP_CLAUSE__SIMT_,
    506 
    507   /* OpenACC clause: independent.  */
    508   OMP_CLAUSE_INDEPENDENT,
    509 
    510   /* OpenACC clause: worker [( [num:] integer-expression)].  */
    511   OMP_CLAUSE_WORKER,
    512 
    513   /* OpenACC clause: vector [( [length:] integer-expression)].  */
    514   OMP_CLAUSE_VECTOR,
    515 
    516   /* OpenACC clause: num_gangs (integer-expression).  */
    517   OMP_CLAUSE_NUM_GANGS,
    518 
    519   /* OpenACC clause: num_workers (integer-expression).  */
    520   OMP_CLAUSE_NUM_WORKERS,
    521 
    522   /* OpenACC clause: vector_length (integer-expression).  */
    523   OMP_CLAUSE_VECTOR_LENGTH,
    524 
    525   /* OpenACC clause: tile ( size-expr-list ).  */
    526   OMP_CLAUSE_TILE,
    527 
    528   /* OpenACC clause: if_present.  */
    529   OMP_CLAUSE_IF_PRESENT,
    530 
    531   /* OpenACC clause: finalize.  */
    532   OMP_CLAUSE_FINALIZE,
    533 
    534   /* OpenACC clause: nohost.  */
    535   OMP_CLAUSE_NOHOST,
    536 };
    537 
    538 #undef DEFTREESTRUCT
    539 #define DEFTREESTRUCT(ENUM, NAME) ENUM,
    540 enum tree_node_structure_enum {
    541 #include "treestruct.def"
    542   LAST_TS_ENUM
    543 };
    544 #undef DEFTREESTRUCT
    545 
    546 enum omp_clause_schedule_kind {
    547   OMP_CLAUSE_SCHEDULE_STATIC,
    548   OMP_CLAUSE_SCHEDULE_DYNAMIC,
    549   OMP_CLAUSE_SCHEDULE_GUIDED,
    550   OMP_CLAUSE_SCHEDULE_AUTO,
    551   OMP_CLAUSE_SCHEDULE_RUNTIME,
    552   OMP_CLAUSE_SCHEDULE_MASK = (1 << 3) - 1,
    553   OMP_CLAUSE_SCHEDULE_MONOTONIC = (1 << 3),
    554   OMP_CLAUSE_SCHEDULE_NONMONOTONIC = (1 << 4),
    555   OMP_CLAUSE_SCHEDULE_LAST = 2 * OMP_CLAUSE_SCHEDULE_NONMONOTONIC - 1
    556 };
    557 
    558 enum omp_clause_default_kind {
    559   OMP_CLAUSE_DEFAULT_UNSPECIFIED,
    560   OMP_CLAUSE_DEFAULT_SHARED,
    561   OMP_CLAUSE_DEFAULT_NONE,
    562   OMP_CLAUSE_DEFAULT_PRIVATE,
    563   OMP_CLAUSE_DEFAULT_FIRSTPRIVATE,
    564   OMP_CLAUSE_DEFAULT_PRESENT,
    565   OMP_CLAUSE_DEFAULT_LAST
    566 };
    567 
    568 enum omp_clause_defaultmap_kind {
    569   OMP_CLAUSE_DEFAULTMAP_CATEGORY_UNSPECIFIED,
    570   OMP_CLAUSE_DEFAULTMAP_CATEGORY_ALL,
    571   OMP_CLAUSE_DEFAULTMAP_CATEGORY_SCALAR,
    572   OMP_CLAUSE_DEFAULTMAP_CATEGORY_AGGREGATE,
    573   OMP_CLAUSE_DEFAULTMAP_CATEGORY_ALLOCATABLE,
    574   OMP_CLAUSE_DEFAULTMAP_CATEGORY_POINTER,
    575   OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK = 7,
    576   OMP_CLAUSE_DEFAULTMAP_ALLOC = 1 * (OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK + 1),
    577   OMP_CLAUSE_DEFAULTMAP_TO = 2 * (OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK + 1),
    578   OMP_CLAUSE_DEFAULTMAP_FROM = 3 * (OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK + 1),
    579   OMP_CLAUSE_DEFAULTMAP_TOFROM = 4 * (OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK + 1),
    580   OMP_CLAUSE_DEFAULTMAP_FIRSTPRIVATE
    581     = 5 * (OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK + 1),
    582   OMP_CLAUSE_DEFAULTMAP_NONE = 6 * (OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK + 1),
    583   OMP_CLAUSE_DEFAULTMAP_DEFAULT
    584     = 7 * (OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK + 1),
    585   OMP_CLAUSE_DEFAULTMAP_PRESENT = 8 * (OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK + 1),
    586   OMP_CLAUSE_DEFAULTMAP_MASK = 15 * (OMP_CLAUSE_DEFAULTMAP_CATEGORY_MASK + 1)
    587 };
    588 
    589 enum omp_clause_bind_kind {
    590   OMP_CLAUSE_BIND_TEAMS,
    591   OMP_CLAUSE_BIND_PARALLEL,
    592   OMP_CLAUSE_BIND_THREAD
    593 };
    594 
    595 /* memory-order-clause on OpenMP atomic/flush constructs or
    596    argument of atomic_default_mem_order clause.  */
    597 enum omp_memory_order {
    598   OMP_MEMORY_ORDER_UNSPECIFIED,
    599   OMP_MEMORY_ORDER_RELAXED,
    600   OMP_MEMORY_ORDER_ACQUIRE,
    601   OMP_MEMORY_ORDER_RELEASE,
    602   OMP_MEMORY_ORDER_ACQ_REL,
    603   OMP_MEMORY_ORDER_SEQ_CST,
    604   OMP_MEMORY_ORDER_MASK = 7,
    605   OMP_FAIL_MEMORY_ORDER_UNSPECIFIED = OMP_MEMORY_ORDER_UNSPECIFIED * 8,
    606   OMP_FAIL_MEMORY_ORDER_RELAXED = OMP_MEMORY_ORDER_RELAXED * 8,
    607   OMP_FAIL_MEMORY_ORDER_ACQUIRE = OMP_MEMORY_ORDER_ACQUIRE * 8,
    608   OMP_FAIL_MEMORY_ORDER_RELEASE = OMP_MEMORY_ORDER_RELEASE * 8,
    609   OMP_FAIL_MEMORY_ORDER_ACQ_REL = OMP_MEMORY_ORDER_ACQ_REL * 8,
    610   OMP_FAIL_MEMORY_ORDER_SEQ_CST = OMP_MEMORY_ORDER_SEQ_CST * 8,
    611   OMP_FAIL_MEMORY_ORDER_MASK = OMP_MEMORY_ORDER_MASK * 8
    612 };
    613 #define OMP_FAIL_MEMORY_ORDER_SHIFT 3
    614 
    615 /* There is a TYPE_QUAL value for each type qualifier.  They can be
    616    combined by bitwise-or to form the complete set of qualifiers for a
    617    type.  */
    618 enum cv_qualifier {
    619   TYPE_UNQUALIFIED   = 0x0,
    620   TYPE_QUAL_CONST    = 0x1,
    621   TYPE_QUAL_VOLATILE = 0x2,
    622   TYPE_QUAL_RESTRICT = 0x4,
    623   TYPE_QUAL_ATOMIC   = 0x8
    624 };
    625 
    626 /* Standard named or nameless data types of the C compiler.  */
    627 enum tree_index {
    628   TI_ERROR_MARK,
    629   TI_INTQI_TYPE,
    630   TI_INTHI_TYPE,
    631   TI_INTSI_TYPE,
    632   TI_INTDI_TYPE,
    633   TI_INTTI_TYPE,
    634 
    635   TI_UINTQI_TYPE,
    636   TI_UINTHI_TYPE,
    637   TI_UINTSI_TYPE,
    638   TI_UINTDI_TYPE,
    639   TI_UINTTI_TYPE,
    640 
    641   TI_ATOMICQI_TYPE,
    642   TI_ATOMICHI_TYPE,
    643   TI_ATOMICSI_TYPE,
    644   TI_ATOMICDI_TYPE,
    645   TI_ATOMICTI_TYPE,
    646 
    647   TI_UINT16_TYPE,
    648   TI_UINT32_TYPE,
    649   TI_UINT64_TYPE,
    650   TI_UINT128_TYPE,
    651 
    652   TI_VOID,
    653 
    654   TI_INTEGER_ZERO,
    655   TI_INTEGER_ONE,
    656   TI_INTEGER_THREE,
    657   TI_INTEGER_MINUS_ONE,
    658   TI_NULL_POINTER,
    659 
    660   TI_SIZE_ZERO,
    661   TI_SIZE_ONE,
    662 
    663   TI_BITSIZE_ZERO,
    664   TI_BITSIZE_ONE,
    665   TI_BITSIZE_UNIT,
    666 
    667   TI_PUBLIC,
    668   TI_PROTECTED,
    669   TI_PRIVATE,
    670 
    671   TI_BOOLEAN_FALSE,
    672   TI_BOOLEAN_TRUE,
    673 
    674   TI_FLOAT_TYPE,
    675   TI_DOUBLE_TYPE,
    676   TI_LONG_DOUBLE_TYPE,
    677 
    678   /* __bf16 type if supported (used in C++ as std::bfloat16_t).  */
    679   TI_BFLOAT16_TYPE,
    680 
    681   /* The _FloatN and _FloatNx types must be consecutive, and in the
    682      same sequence as the corresponding complex types, which must also
    683      be consecutive; _FloatN must come before _FloatNx; the order must
    684      also be the same as in the floatn_nx_types array and the RID_*
    685      values in c-common.h.  This is so that iterations over these
    686      types work as intended.  */
    687   TI_FLOAT16_TYPE,
    688   TI_FLOATN_TYPE_FIRST = TI_FLOAT16_TYPE,
    689   TI_FLOATN_NX_TYPE_FIRST = TI_FLOAT16_TYPE,
    690   TI_FLOAT32_TYPE,
    691   TI_FLOAT64_TYPE,
    692   TI_FLOAT128_TYPE,
    693   TI_FLOATN_TYPE_LAST = TI_FLOAT128_TYPE,
    694 #define NUM_FLOATN_TYPES (TI_FLOATN_TYPE_LAST - TI_FLOATN_TYPE_FIRST + 1)
    695   TI_FLOAT32X_TYPE,
    696   TI_FLOATNX_TYPE_FIRST = TI_FLOAT32X_TYPE,
    697   TI_FLOAT64X_TYPE,
    698   TI_FLOAT128X_TYPE,
    699   TI_FLOATNX_TYPE_LAST = TI_FLOAT128X_TYPE,
    700   TI_FLOATN_NX_TYPE_LAST = TI_FLOAT128X_TYPE,
    701 #define NUM_FLOATNX_TYPES (TI_FLOATNX_TYPE_LAST - TI_FLOATNX_TYPE_FIRST + 1)
    702 #define NUM_FLOATN_NX_TYPES (TI_FLOATN_NX_TYPE_LAST		\
    703 			     - TI_FLOATN_NX_TYPE_FIRST		\
    704 			     + 1)
    705 
    706   /* Type used by certain backends for __float128, which in C++ should be
    707      distinct type from _Float128 for backwards compatibility reasons.  */
    708   TI_FLOAT128T_TYPE,
    709 
    710   /* Put the complex types after their component types, so that in (sequential)
    711      tree streaming we can assert that their component types have already been
    712      handled (see tree-streamer.cc:record_common_node).  */
    713   TI_COMPLEX_INTEGER_TYPE,
    714   TI_COMPLEX_FLOAT_TYPE,
    715   TI_COMPLEX_DOUBLE_TYPE,
    716   TI_COMPLEX_LONG_DOUBLE_TYPE,
    717 
    718   TI_COMPLEX_FLOAT16_TYPE,
    719   TI_COMPLEX_FLOATN_NX_TYPE_FIRST = TI_COMPLEX_FLOAT16_TYPE,
    720   TI_COMPLEX_FLOAT32_TYPE,
    721   TI_COMPLEX_FLOAT64_TYPE,
    722   TI_COMPLEX_FLOAT128_TYPE,
    723   TI_COMPLEX_FLOAT32X_TYPE,
    724   TI_COMPLEX_FLOAT64X_TYPE,
    725   TI_COMPLEX_FLOAT128X_TYPE,
    726 
    727   TI_FLOAT_PTR_TYPE,
    728   TI_DOUBLE_PTR_TYPE,
    729   TI_LONG_DOUBLE_PTR_TYPE,
    730   TI_INTEGER_PTR_TYPE,
    731 
    732   TI_VOID_TYPE,
    733   TI_PTR_TYPE,
    734   TI_CONST_PTR_TYPE,
    735   TI_SIZE_TYPE,
    736   TI_PID_TYPE,
    737   TI_PTRDIFF_TYPE,
    738   TI_VA_LIST_TYPE,
    739   TI_VA_LIST_GPR_COUNTER_FIELD,
    740   TI_VA_LIST_FPR_COUNTER_FIELD,
    741   TI_BOOLEAN_TYPE,
    742   TI_FILEPTR_TYPE,
    743   TI_CONST_TM_PTR_TYPE,
    744   TI_FENV_T_PTR_TYPE,
    745   TI_CONST_FENV_T_PTR_TYPE,
    746   TI_FEXCEPT_T_PTR_TYPE,
    747   TI_CONST_FEXCEPT_T_PTR_TYPE,
    748   TI_POINTER_SIZED_TYPE,
    749 
    750   TI_DFLOAT32_TYPE,
    751   TI_DFLOAT64_TYPE,
    752   TI_DFLOAT128_TYPE,
    753 
    754   TI_VOID_LIST_NODE,
    755 
    756   TI_MAIN_IDENTIFIER,
    757 
    758   TI_SAT_SFRACT_TYPE,
    759   TI_SAT_FRACT_TYPE,
    760   TI_SAT_LFRACT_TYPE,
    761   TI_SAT_LLFRACT_TYPE,
    762   TI_SAT_USFRACT_TYPE,
    763   TI_SAT_UFRACT_TYPE,
    764   TI_SAT_ULFRACT_TYPE,
    765   TI_SAT_ULLFRACT_TYPE,
    766   TI_SFRACT_TYPE,
    767   TI_FRACT_TYPE,
    768   TI_LFRACT_TYPE,
    769   TI_LLFRACT_TYPE,
    770   TI_USFRACT_TYPE,
    771   TI_UFRACT_TYPE,
    772   TI_ULFRACT_TYPE,
    773   TI_ULLFRACT_TYPE,
    774   TI_SAT_SACCUM_TYPE,
    775   TI_SAT_ACCUM_TYPE,
    776   TI_SAT_LACCUM_TYPE,
    777   TI_SAT_LLACCUM_TYPE,
    778   TI_SAT_USACCUM_TYPE,
    779   TI_SAT_UACCUM_TYPE,
    780   TI_SAT_ULACCUM_TYPE,
    781   TI_SAT_ULLACCUM_TYPE,
    782   TI_SACCUM_TYPE,
    783   TI_ACCUM_TYPE,
    784   TI_LACCUM_TYPE,
    785   TI_LLACCUM_TYPE,
    786   TI_USACCUM_TYPE,
    787   TI_UACCUM_TYPE,
    788   TI_ULACCUM_TYPE,
    789   TI_ULLACCUM_TYPE,
    790   TI_QQ_TYPE,
    791   TI_HQ_TYPE,
    792   TI_SQ_TYPE,
    793   TI_DQ_TYPE,
    794   TI_TQ_TYPE,
    795   TI_UQQ_TYPE,
    796   TI_UHQ_TYPE,
    797   TI_USQ_TYPE,
    798   TI_UDQ_TYPE,
    799   TI_UTQ_TYPE,
    800   TI_SAT_QQ_TYPE,
    801   TI_SAT_HQ_TYPE,
    802   TI_SAT_SQ_TYPE,
    803   TI_SAT_DQ_TYPE,
    804   TI_SAT_TQ_TYPE,
    805   TI_SAT_UQQ_TYPE,
    806   TI_SAT_UHQ_TYPE,
    807   TI_SAT_USQ_TYPE,
    808   TI_SAT_UDQ_TYPE,
    809   TI_SAT_UTQ_TYPE,
    810   TI_HA_TYPE,
    811   TI_SA_TYPE,
    812   TI_DA_TYPE,
    813   TI_TA_TYPE,
    814   TI_UHA_TYPE,
    815   TI_USA_TYPE,
    816   TI_UDA_TYPE,
    817   TI_UTA_TYPE,
    818   TI_SAT_HA_TYPE,
    819   TI_SAT_SA_TYPE,
    820   TI_SAT_DA_TYPE,
    821   TI_SAT_TA_TYPE,
    822   TI_SAT_UHA_TYPE,
    823   TI_SAT_USA_TYPE,
    824   TI_SAT_UDA_TYPE,
    825   TI_SAT_UTA_TYPE,
    826 
    827   TI_MODULE_HWM,
    828   /* Nodes below here change during compilation, and should therefore
    829      not be in the C++ module's global tree table.  */
    830 
    831   TI_OPTIMIZATION_DEFAULT,
    832   TI_OPTIMIZATION_CURRENT,
    833   TI_TARGET_OPTION_DEFAULT,
    834   TI_TARGET_OPTION_CURRENT,
    835   TI_CURRENT_TARGET_PRAGMA,
    836   TI_CURRENT_OPTIMIZE_PRAGMA,
    837 
    838   TI_CHREC_DONT_KNOW,
    839   TI_CHREC_KNOWN,
    840 
    841   TI_MAX
    842 };
    843 
    844 /* An enumeration of the standard C integer types.  These must be
    845    ordered so that shorter types appear before longer ones, and so
    846    that signed types appear before unsigned ones, for the correct
    847    functioning of interpret_integer() in c-lex.cc.  */
    848 enum integer_type_kind {
    849   itk_char,
    850   itk_signed_char,
    851   itk_unsigned_char,
    852   itk_short,
    853   itk_unsigned_short,
    854   itk_int,
    855   itk_unsigned_int,
    856   itk_long,
    857   itk_unsigned_long,
    858   itk_long_long,
    859   itk_unsigned_long_long,
    860 
    861   itk_intN_0,
    862   itk_unsigned_intN_0,
    863   itk_intN_1,
    864   itk_unsigned_intN_1,
    865   itk_intN_2,
    866   itk_unsigned_intN_2,
    867   itk_intN_3,
    868   itk_unsigned_intN_3,
    869 
    870   itk_none
    871 };
    872 
    873 /* A pointer-to-function member type looks like:
    874 
    875      struct {
    876        __P __pfn;
    877        ptrdiff_t __delta;
    878      };
    879 
    880    If __pfn is NULL, it is a NULL pointer-to-member-function.
    881 
    882    (Because the vtable is always the first thing in the object, we
    883    don't need its offset.)  If the function is virtual, then PFN is
    884    one plus twice the index into the vtable; otherwise, it is just a
    885    pointer to the function.
    886 
    887    Unfortunately, using the lowest bit of PFN doesn't work in
    888    architectures that don't impose alignment requirements on function
    889    addresses, or that use the lowest bit to tell one ISA from another,
    890    for example.  For such architectures, we use the lowest bit of
    891    DELTA instead of the lowest bit of the PFN, and DELTA will be
    892    multiplied by 2.  */
    893 enum ptrmemfunc_vbit_where_t {
    894   ptrmemfunc_vbit_in_pfn,
    895   ptrmemfunc_vbit_in_delta
    896 };
    897 
    898 /* Flags that may be passed in the third argument of decl_attributes, and
    899    to handler functions for attributes.  */
    900 enum attribute_flags {
    901   /* The type passed in is the type of a DECL, and any attributes that
    902      should be passed in again to be applied to the DECL rather than the
    903      type should be returned.  */
    904   ATTR_FLAG_DECL_NEXT = 1,
    905   /* The type passed in is a function return type, and any attributes that
    906      should be passed in again to be applied to the function type rather
    907      than the return type should be returned.  */
    908   ATTR_FLAG_FUNCTION_NEXT = 2,
    909   /* The type passed in is an array element type, and any attributes that
    910      should be passed in again to be applied to the array type rather
    911      than the element type should be returned.  */
    912   ATTR_FLAG_ARRAY_NEXT = 4,
    913   /* The type passed in is a structure, union or enumeration type being
    914      created, and should be modified in place.  */
    915   ATTR_FLAG_TYPE_IN_PLACE = 8,
    916   /* The attributes are being applied by default to a library function whose
    917      name indicates known behavior, and should be silently ignored if they
    918      are not in fact compatible with the function type.  */
    919   ATTR_FLAG_BUILT_IN = 16,
    920   /* A given attribute has been parsed as a C++-11 attribute.  */
    921   ATTR_FLAG_CXX11 = 32,
    922   /* The attribute handler is being invoked with an internal argument
    923      that may not otherwise be valid when specified in source code.  */
    924   ATTR_FLAG_INTERNAL = 64
    925 };
    926 
    927 /* Types used to represent sizes.  */
    928 enum size_type_kind {
    929   stk_sizetype,		/* Normal representation of sizes in bytes.  */
    930   stk_ssizetype,	/* Signed representation of sizes in bytes.  */
    931   stk_bitsizetype,	/* Normal representation of sizes in bits.  */
    932   stk_sbitsizetype,	/* Signed representation of sizes in bits.  */
    933   stk_type_kind_last
    934 };
    935 
    936 /* Flags controlling operand_equal_p() behavior.  */
    937 enum operand_equal_flag {
    938   OEP_ONLY_CONST = 1,
    939   OEP_PURE_SAME = 2,
    940   OEP_MATCH_SIDE_EFFECTS = 4,
    941   OEP_ADDRESS_OF = 8,
    942   /* Internal within operand_equal_p:  */
    943   OEP_NO_HASH_CHECK = 16,
    944   /* Internal within inchash::add_expr:  */
    945   OEP_HASH_CHECK = 32,
    946   /* Makes operand_equal_p handle more expressions:  */
    947   OEP_LEXICOGRAPHIC = 64,
    948   OEP_BITWISE = 128,
    949   /* For OEP_ADDRESS_OF of COMPONENT_REFs, only consider same fields as
    950      equivalent rather than also different fields with the same offset.  */
    951   OEP_ADDRESS_OF_SAME_FIELD = 256,
    952   /* In conjunction with OEP_LEXICOGRAPHIC considers names of declarations
    953      of the same kind.  Used to compare VLA bounds involving parameters
    954      across redeclarations of the same function.  */
    955   OEP_DECL_NAME = 512
    956 };
    957 
    958 /* Enum and arrays used for tree allocation stats.
    959    Keep in sync with tree.cc:tree_node_kind_names.  */
    960 enum tree_node_kind {
    961   d_kind,
    962   t_kind,
    963   b_kind,
    964   s_kind,
    965   r_kind,
    966   e_kind,
    967   c_kind,
    968   id_kind,
    969   vec_kind,
    970   binfo_kind,
    971   ssa_name_kind,
    972   constr_kind,
    973   x_kind,
    974   lang_decl,
    975   lang_type,
    976   omp_clause_kind,
    977   all_kinds
    978 };
    979 
    980 enum annot_expr_kind {
    981   annot_expr_ivdep_kind,
    982   annot_expr_unroll_kind,
    983   annot_expr_no_vector_kind,
    984   annot_expr_vector_kind,
    985   annot_expr_parallel_kind,
    986   annot_expr_maybe_infinite_kind,
    987   annot_expr_kind_last
    988 };
    989 
    990 /* The kind of a TREE_CLOBBER_P CONSTRUCTOR node.  Other than _UNDEF, these are
    991    in roughly sequential order.  */
    992 enum clobber_kind {
    993   /* Unspecified, this clobber acts as a store of an undefined value.  */
    994   CLOBBER_UNDEF,
    995   /* Beginning of storage duration, e.g. malloc.  */
    996   CLOBBER_STORAGE_BEGIN,
    997   /* Beginning of object data, e.g. start of C++ constructor.  This differs
    998      from C++ 'lifetime', which starts when initialization is complete; a
    999      clobber there would discard the initialization.  */
   1000   CLOBBER_OBJECT_BEGIN,
   1001   /* End of object data, e.g. end of C++ destructor.  */
   1002   CLOBBER_OBJECT_END,
   1003   /* End of storage duration, e.g. free.  */
   1004   CLOBBER_STORAGE_END,
   1005   CLOBBER_LAST
   1006 };
   1007 
   1008 /*---------------------------------------------------------------------------
   1009                                 Type definitions
   1010 ---------------------------------------------------------------------------*/
   1011 /* When processing aliases at the symbol table level, we need the
   1012    declaration of target. For this reason we need to queue aliases and
   1013    process them after all declarations has been produced.  */
   1014 struct GTY(()) alias_pair {
   1015   tree decl;
   1016   tree target;
   1017 };
   1018 
   1019 /* An initialization priority.  */
   1020 typedef unsigned short priority_type;
   1021 
   1022 /* The type of a callback function for walking over tree structure.  */
   1023 typedef tree (*walk_tree_fn) (tree *, int *, void *);
   1024 
   1025 /* The type of a callback function that represents a custom walk_tree.  */
   1026 typedef tree (*walk_tree_lh) (tree *, int *, tree (*) (tree *, int *, void *),
   1027 			      void *, hash_set<tree> *);
   1028 
   1029 
   1030 /*---------------------------------------------------------------------------
   1031                               Main data structures
   1032 ---------------------------------------------------------------------------*/
   1033 /* A tree node can represent a data type, a variable, an expression
   1034    or a statement.  Each node has a TREE_CODE which says what kind of
   1035    thing it represents.  Some common codes are:
   1036    INTEGER_TYPE -- represents a type of integers.
   1037    ARRAY_TYPE -- represents a type of pointer.
   1038    VAR_DECL -- represents a declared variable.
   1039    INTEGER_CST -- represents a constant integer value.
   1040    PLUS_EXPR -- represents a sum (an expression).
   1041 
   1042    As for the contents of a tree node: there are some fields
   1043    that all nodes share.  Each TREE_CODE has various special-purpose
   1044    fields as well.  The fields of a node are never accessed directly,
   1045    always through accessor macros.  */
   1046 
   1047 /* Every kind of tree node starts with this structure,
   1048    so all nodes have these fields.
   1049 
   1050    See the accessor macros, defined below, for documentation of the
   1051    fields, and the table below which connects the fields and the
   1052    accessor macros.  */
   1053 
   1054 struct GTY(()) tree_base {
   1055   ENUM_BITFIELD(tree_code) code : 16;
   1056 
   1057   unsigned side_effects_flag : 1;
   1058   unsigned constant_flag : 1;
   1059   unsigned addressable_flag : 1;
   1060   unsigned volatile_flag : 1;
   1061   unsigned readonly_flag : 1;
   1062   unsigned asm_written_flag: 1;
   1063   unsigned nowarning_flag : 1;
   1064   unsigned visited : 1;
   1065 
   1066   unsigned used_flag : 1;
   1067   unsigned nothrow_flag : 1;
   1068   unsigned static_flag : 1;
   1069   unsigned public_flag : 1;
   1070   unsigned private_flag : 1;
   1071   unsigned protected_flag : 1;
   1072   unsigned deprecated_flag : 1;
   1073   unsigned default_def_flag : 1;
   1074 
   1075   union {
   1076     /* The bits in the following structure should only be used with
   1077        accessor macros that constrain inputs with tree checking.  */
   1078     struct {
   1079       unsigned lang_flag_0 : 1;
   1080       unsigned lang_flag_1 : 1;
   1081       unsigned lang_flag_2 : 1;
   1082       unsigned lang_flag_3 : 1;
   1083       unsigned lang_flag_4 : 1;
   1084       unsigned lang_flag_5 : 1;
   1085       unsigned lang_flag_6 : 1;
   1086       unsigned saturating_flag : 1;
   1087 
   1088       unsigned unsigned_flag : 1;
   1089       unsigned packed_flag : 1;
   1090       unsigned user_align : 1;
   1091       unsigned nameless_flag : 1;
   1092       unsigned atomic_flag : 1;
   1093       unsigned unavailable_flag : 1;
   1094       unsigned spare0 : 2;
   1095 
   1096       unsigned spare1 : 8;
   1097 
   1098       /* For _TYPE nodes, this is TYPE_ADDR_SPACE; the reason it is
   1099 	 present in tree_base instead of tree_type is to save space.  The size
   1100 	 of the field must be large enough to hold addr_space_t values.
   1101 	 For CONSTRUCTOR nodes this holds the clobber_kind enum.
   1102 	 The C++ front-end uses this in IDENTIFIER_NODE and NAMESPACE_DECL.  */
   1103       unsigned address_space : 8;
   1104     } bits;
   1105 
   1106     /* The following fields are present in tree_base to save space.  The
   1107        nodes using them do not require any of the flags above and so can
   1108        make better use of the 4-byte sized word.  */
   1109 
   1110     /* The number of HOST_WIDE_INTs in an INTEGER_CST.  */
   1111     struct {
   1112       /* The number of HOST_WIDE_INTs if the INTEGER_CST is accessed in
   1113 	 its native precision.  */
   1114       unsigned short unextended;
   1115 
   1116       /* The number of HOST_WIDE_INTs if the INTEGER_CST is extended to
   1117 	 wider precisions based on its TYPE_SIGN.  */
   1118       unsigned short extended;
   1119     } int_length;
   1120 
   1121     /* VEC length.  This field is only used with TREE_VEC.  */
   1122     int length;
   1123 
   1124     /* This field is only used with VECTOR_CST.  */
   1125     struct {
   1126       /* The value of VECTOR_CST_LOG2_NPATTERNS.  */
   1127       unsigned int log2_npatterns : 8;
   1128 
   1129       /* The value of VECTOR_CST_NELTS_PER_PATTERN.  */
   1130       unsigned int nelts_per_pattern : 8;
   1131 
   1132       /* For future expansion.  */
   1133       unsigned int unused : 16;
   1134     } vector_cst;
   1135 
   1136     /* SSA version number.  This field is only used with SSA_NAME.  */
   1137     unsigned int version;
   1138 
   1139     /* CHREC_VARIABLE.  This field is only used with POLYNOMIAL_CHREC.  */
   1140     unsigned int chrec_var;
   1141 
   1142     /* Internal function code.  */
   1143     enum internal_fn ifn;
   1144 
   1145     /* OMP_ATOMIC* memory order.  */
   1146     enum omp_memory_order omp_atomic_memory_order;
   1147 
   1148     /* The following two fields are used for MEM_REF and TARGET_MEM_REF
   1149        expression trees and specify known data non-dependences.  For
   1150        two memory references in a function they are known to not
   1151        alias if dependence_info.clique are equal and dependence_info.base
   1152        are distinct.  Clique number zero means there is no information,
   1153        clique number one is populated from function global information
   1154        and thus needs no remapping on transforms like loop unrolling.  */
   1155     struct {
   1156       unsigned short clique;
   1157       unsigned short base;
   1158     } dependence_info;
   1159   } GTY((skip(""))) u;
   1160 };
   1161 
   1162 /* The following table lists the uses of each of the above flags and
   1163    for which types of nodes they are defined.
   1164 
   1165    addressable_flag:
   1166 
   1167        TREE_ADDRESSABLE in
   1168            VAR_DECL, PARM_DECL, RESULT_DECL, FUNCTION_DECL, LABEL_DECL
   1169            SSA_NAME
   1170            all types
   1171            CONSTRUCTOR, IDENTIFIER_NODE
   1172            STMT_EXPR
   1173 
   1174        CALL_EXPR_TAILCALL in
   1175            CALL_EXPR
   1176 
   1177        CASE_LOW_SEEN in
   1178            CASE_LABEL_EXPR
   1179 
   1180        PREDICT_EXPR_OUTCOME in
   1181 	   PREDICT_EXPR
   1182 
   1183        OMP_CLAUSE_MAP_DECL_MAKE_ADDRESSABLE in
   1184 	   OMP_CLAUSE
   1185 
   1186    static_flag:
   1187 
   1188        TREE_STATIC in
   1189            VAR_DECL, FUNCTION_DECL
   1190            CONSTRUCTOR
   1191 
   1192        TREE_NO_TRAMPOLINE in
   1193            ADDR_EXPR
   1194 
   1195        BINFO_VIRTUAL_P in
   1196            TREE_BINFO
   1197 
   1198        TREE_SYMBOL_REFERENCED in
   1199            IDENTIFIER_NODE
   1200 
   1201        CLEANUP_EH_ONLY in
   1202            TARGET_EXPR, WITH_CLEANUP_EXPR
   1203 
   1204        TRY_CATCH_IS_CLEANUP in
   1205            TRY_CATCH_EXPR
   1206 
   1207        ASM_INPUT_P in
   1208            ASM_EXPR
   1209 
   1210        TYPE_REF_CAN_ALIAS_ALL in
   1211            POINTER_TYPE, REFERENCE_TYPE
   1212 
   1213        CASE_HIGH_SEEN in
   1214            CASE_LABEL_EXPR
   1215 
   1216        ENUM_IS_SCOPED in
   1217 	   ENUMERAL_TYPE
   1218 
   1219        TRANSACTION_EXPR_OUTER in
   1220 	   TRANSACTION_EXPR
   1221 
   1222        MUST_TAIL_CALL in
   1223 	   CALL_EXPR
   1224 
   1225    public_flag:
   1226 
   1227        TREE_OVERFLOW in
   1228            INTEGER_CST, REAL_CST, COMPLEX_CST, VECTOR_CST
   1229 
   1230        TREE_PUBLIC in
   1231            VAR_DECL, FUNCTION_DECL
   1232            IDENTIFIER_NODE
   1233 
   1234        CONSTRUCTOR_NO_CLEARING in
   1235            CONSTRUCTOR
   1236 
   1237        ASM_VOLATILE_P in
   1238            ASM_EXPR
   1239 
   1240        CALL_EXPR_VA_ARG_PACK in
   1241            CALL_EXPR
   1242 
   1243        TYPE_CACHED_VALUES_P in
   1244            all types
   1245 
   1246        SAVE_EXPR_RESOLVED_P in
   1247            SAVE_EXPR
   1248 
   1249        OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE in
   1250            OMP_CLAUSE_LASTPRIVATE
   1251 
   1252        OMP_CLAUSE_PRIVATE_DEBUG in
   1253            OMP_CLAUSE_PRIVATE
   1254 
   1255        OMP_CLAUSE_LINEAR_NO_COPYIN in
   1256 	   OMP_CLAUSE_LINEAR
   1257 
   1258        OMP_CLAUSE_MAP_ZERO_BIAS_ARRAY_SECTION in
   1259 	   OMP_CLAUSE_MAP
   1260 
   1261        OMP_CLAUSE_REDUCTION_OMP_ORIG_REF in
   1262 	   OMP_CLAUSE_{,TASK_,IN_}REDUCTION
   1263 
   1264        OMP_CLAUSE_USE_DEVICE_PTR_IF_PRESENT in
   1265 	   OMP_CLAUSE_USE_DEVICE_PTR
   1266 
   1267        TRANSACTION_EXPR_RELAXED in
   1268 	   TRANSACTION_EXPR
   1269 
   1270        FALLTHROUGH_LABEL_P in
   1271 	   LABEL_DECL
   1272 
   1273        SSA_NAME_IS_VIRTUAL_OPERAND in
   1274 	   SSA_NAME
   1275 
   1276        EXPR_LOCATION_WRAPPER_P in
   1277 	   NON_LVALUE_EXPR, VIEW_CONVERT_EXPR
   1278 
   1279    private_flag:
   1280 
   1281        TREE_PRIVATE in
   1282            all decls
   1283 
   1284        CALL_EXPR_RETURN_SLOT_OPT in
   1285            CALL_EXPR
   1286 
   1287        OMP_SECTION_LAST in
   1288            OMP_SECTION
   1289 
   1290        OMP_PARALLEL_COMBINED in
   1291            OMP_PARALLEL
   1292 
   1293        OMP_CLAUSE_PRIVATE_OUTER_REF in
   1294 	   OMP_CLAUSE_PRIVATE
   1295 
   1296        OMP_CLAUSE_LINEAR_NO_COPYOUT in
   1297 	   OMP_CLAUSE_LINEAR
   1298 
   1299        TYPE_REF_IS_RVALUE in
   1300 	   REFERENCE_TYPE
   1301 
   1302        ENUM_IS_OPAQUE in
   1303 	   ENUMERAL_TYPE
   1304 
   1305    protected_flag:
   1306 
   1307        TREE_PROTECTED in
   1308            BLOCK
   1309            all decls
   1310 
   1311        CALL_FROM_THUNK_P and
   1312        CALL_ALLOCA_FOR_VAR_P and
   1313        CALL_FROM_NEW_OR_DELETE_P in
   1314            CALL_EXPR
   1315 
   1316        OMP_CLAUSE_LINEAR_VARIABLE_STRIDE in
   1317 	   OMP_CLAUSE_LINEAR
   1318 
   1319        ASM_INLINE_P in
   1320 	   ASM_EXPR
   1321 
   1322    side_effects_flag:
   1323 
   1324        TREE_SIDE_EFFECTS in
   1325            all expressions
   1326            all decls
   1327            all constants
   1328 
   1329        FORCED_LABEL in
   1330            LABEL_DECL
   1331 
   1332    volatile_flag:
   1333 
   1334        TREE_THIS_VOLATILE in
   1335            all expressions
   1336            all decls
   1337 
   1338        TYPE_VOLATILE in
   1339            all types
   1340 
   1341    readonly_flag:
   1342 
   1343        TREE_READONLY in
   1344            all expressions
   1345            all decls
   1346 
   1347        TYPE_READONLY in
   1348            all types
   1349 
   1350        OMP_CLAUSE_MAP_READONLY in
   1351            OMP_CLAUSE_MAP
   1352 
   1353        OMP_CLAUSE__CACHE__READONLY in
   1354            OMP_CLAUSE__CACHE_
   1355 
   1356    constant_flag:
   1357 
   1358        TREE_CONSTANT in
   1359            all expressions
   1360            all decls
   1361            all constants
   1362 
   1363        TYPE_SIZES_GIMPLIFIED in
   1364            all types
   1365 
   1366    unsigned_flag:
   1367 
   1368        TYPE_UNSIGNED in
   1369            all types
   1370 
   1371        DECL_UNSIGNED in
   1372            all decls
   1373 
   1374    asm_written_flag:
   1375 
   1376        TREE_ASM_WRITTEN in
   1377            VAR_DECL, FUNCTION_DECL, TYPE_DECL
   1378            RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE
   1379            BLOCK, STRING_CST
   1380 
   1381        SSA_NAME_OCCURS_IN_ABNORMAL_PHI in
   1382            SSA_NAME
   1383 
   1384    used_flag:
   1385 
   1386        TREE_USED in
   1387            all expressions
   1388            all decls
   1389            IDENTIFIER_NODE
   1390 
   1391    nothrow_flag:
   1392 
   1393        TREE_NOTHROW in
   1394            CALL_EXPR
   1395            FUNCTION_DECL
   1396 
   1397        TREE_THIS_NOTRAP in
   1398           INDIRECT_REF, MEM_REF, TARGET_MEM_REF, ARRAY_REF, ARRAY_RANGE_REF
   1399 
   1400        SSA_NAME_IN_FREE_LIST in
   1401           SSA_NAME
   1402 
   1403        DECL_NONALIASED in
   1404 	  VAR_DECL
   1405 
   1406        CHREC_NOWRAP in
   1407 	  POLYNOMIAL_CHREC
   1408 
   1409    deprecated_flag:
   1410 
   1411        TREE_DEPRECATED in
   1412            all decls
   1413 	   all types
   1414 
   1415        IDENTIFIER_TRANSPARENT_ALIAS in
   1416            IDENTIFIER_NODE
   1417 
   1418        SSA_NAME_POINTS_TO_READONLY_MEMORY in
   1419 	   SSA_NAME
   1420 
   1421    unavailable_flag:
   1422 
   1423        TREE_UNAVAILABLE in
   1424 	   all decls
   1425 	   all types
   1426 
   1427    visited:
   1428 
   1429        TREE_VISITED in
   1430            all trees (used liberally by many passes)
   1431 
   1432    saturating_flag:
   1433 
   1434        TYPE_REVERSE_STORAGE_ORDER in
   1435            RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE, ARRAY_TYPE
   1436 
   1437        TYPE_SATURATING in
   1438            other types
   1439 
   1440        VAR_DECL_IS_VIRTUAL_OPERAND in
   1441 	   VAR_DECL
   1442 
   1443    nowarning_flag:
   1444 
   1445        TREE_NO_WARNING in
   1446            all expressions
   1447            all decls
   1448 
   1449        TYPE_ARTIFICIAL in
   1450            all types
   1451 
   1452    default_def_flag:
   1453 
   1454        TYPE_FINAL_P in
   1455 	   RECORD_TYPE, UNION_TYPE and QUAL_UNION_TYPE
   1456 
   1457        TYPE_VECTOR_OPAQUE in
   1458 	   VECTOR_TYPE
   1459 
   1460        SSA_NAME_IS_DEFAULT_DEF in
   1461            SSA_NAME
   1462 
   1463        DECL_NONLOCAL_FRAME in
   1464 	   VAR_DECL
   1465 
   1466        REF_REVERSE_STORAGE_ORDER in
   1467            BIT_FIELD_REF, MEM_REF
   1468 
   1469        FUNC_ADDR_BY_DESCRIPTOR in
   1470            ADDR_EXPR
   1471 
   1472        CALL_EXPR_BY_DESCRIPTOR in
   1473            CALL_EXPR
   1474 
   1475 */
   1476 
   1477 struct GTY(()) tree_typed {
   1478   struct tree_base base;
   1479   tree type;
   1480 };
   1481 
   1482 struct GTY(()) tree_common {
   1483   struct tree_typed typed;
   1484   tree chain;
   1485 };
   1486 
   1487 struct GTY(()) tree_int_cst {
   1488   struct tree_typed typed;
   1489   HOST_WIDE_INT val[1];
   1490 };
   1491 
   1492 
   1493 struct GTY(()) tree_real_cst {
   1494   struct tree_typed typed;
   1495   struct real_value value;
   1496 };
   1497 
   1498 struct GTY(()) tree_fixed_cst {
   1499   struct tree_typed typed;
   1500   struct fixed_value * fixed_cst_ptr;
   1501 };
   1502 
   1503 struct GTY(()) tree_string {
   1504   struct tree_typed typed;
   1505   int length;
   1506   char str[1];
   1507 };
   1508 
   1509 struct GTY(()) tree_complex {
   1510   struct tree_typed typed;
   1511   tree real;
   1512   tree imag;
   1513 };
   1514 
   1515 struct GTY(()) tree_vector {
   1516   struct tree_typed typed;
   1517   tree GTY ((length ("vector_cst_encoded_nelts ((tree) &%h)"))) elts[1];
   1518 };
   1519 
   1520 struct GTY(()) tree_poly_int_cst {
   1521   struct tree_typed typed;
   1522   tree coeffs[NUM_POLY_INT_COEFFS];
   1523 };
   1524 
   1525 struct GTY(()) tree_identifier {
   1526   struct tree_common common;
   1527   struct ht_identifier id;
   1528 };
   1529 
   1530 struct GTY(()) tree_list {
   1531   struct tree_common common;
   1532   tree purpose;
   1533   tree value;
   1534 };
   1535 
   1536 struct GTY(()) tree_vec {
   1537   struct tree_common common;
   1538   tree GTY ((length ("TREE_VEC_LENGTH ((tree)&%h)"))) a[1];
   1539 };
   1540 
   1541 /* A single element of a CONSTRUCTOR. VALUE holds the actual value of the
   1542    element. INDEX can optionally design the position of VALUE: in arrays,
   1543    it is the index where VALUE has to be placed; in structures, it is the
   1544    FIELD_DECL of the member.  */
   1545 struct GTY(()) constructor_elt {
   1546   tree index;
   1547   tree value;
   1548 };
   1549 
   1550 struct GTY(()) tree_constructor {
   1551   struct tree_typed typed;
   1552   vec<constructor_elt, va_gc> *elts;
   1553 };
   1554 
   1555 enum omp_clause_depend_kind
   1556 {
   1557   OMP_CLAUSE_DEPEND_IN,
   1558   OMP_CLAUSE_DEPEND_OUT,
   1559   OMP_CLAUSE_DEPEND_INOUT,
   1560   OMP_CLAUSE_DEPEND_MUTEXINOUTSET,
   1561   OMP_CLAUSE_DEPEND_INOUTSET,
   1562   OMP_CLAUSE_DEPEND_DEPOBJ,
   1563   OMP_CLAUSE_DEPEND_INVALID,
   1564   OMP_CLAUSE_DEPEND_LAST
   1565 };
   1566 
   1567 enum omp_clause_doacross_kind
   1568 {
   1569   OMP_CLAUSE_DOACROSS_SOURCE,
   1570   OMP_CLAUSE_DOACROSS_SINK,
   1571   OMP_CLAUSE_DOACROSS_LAST
   1572 };
   1573 
   1574 enum omp_clause_proc_bind_kind
   1575 {
   1576   /* Numbers should match omp_proc_bind_t enum in omp.h.  */
   1577   OMP_CLAUSE_PROC_BIND_FALSE = 0,
   1578   OMP_CLAUSE_PROC_BIND_TRUE = 1,
   1579   OMP_CLAUSE_PROC_BIND_PRIMARY = 2,
   1580   OMP_CLAUSE_PROC_BIND_MASTER = 2,
   1581   OMP_CLAUSE_PROC_BIND_CLOSE = 3,
   1582   OMP_CLAUSE_PROC_BIND_SPREAD = 4,
   1583   OMP_CLAUSE_PROC_BIND_LAST
   1584 };
   1585 
   1586 enum omp_clause_device_type_kind
   1587 {
   1588   OMP_CLAUSE_DEVICE_TYPE_HOST = 1,
   1589   OMP_CLAUSE_DEVICE_TYPE_NOHOST = 2,
   1590   OMP_CLAUSE_DEVICE_TYPE_ANY = 3
   1591 };
   1592 
   1593 enum omp_clause_linear_kind
   1594 {
   1595   OMP_CLAUSE_LINEAR_DEFAULT,
   1596   OMP_CLAUSE_LINEAR_REF,
   1597   OMP_CLAUSE_LINEAR_VAL,
   1598   OMP_CLAUSE_LINEAR_UVAL
   1599 };
   1600 
   1601 struct GTY(()) tree_exp {
   1602   struct tree_typed typed;
   1603   location_t locus;
   1604   /* Discriminator for basic conditions in a Boolean expressions.  Trees that
   1605      are operands of the same Boolean expression should have the same uid.  */
   1606   unsigned condition_uid;
   1607   tree GTY ((length ("TREE_OPERAND_LENGTH ((tree)&%h)"))) operands[1];
   1608 };
   1609 
   1610 /* Immediate use linking structure.  This structure is used for maintaining
   1611    a doubly linked list of uses of an SSA_NAME.  */
   1612 struct GTY(()) ssa_use_operand_t {
   1613   struct ssa_use_operand_t* GTY((skip(""))) prev;
   1614   struct ssa_use_operand_t* GTY((skip(""))) next;
   1615   /* Immediate uses for a given SSA name are maintained as a cyclic
   1616      list.  To recognize the root of this list, the location field
   1617      needs to point to the original SSA name.  Since statements and
   1618      SSA names are of different data types, we need this union.  See
   1619      the explanation in struct imm_use_iterator.  */
   1620   union { gimple *stmt; tree ssa_name; } GTY((skip(""))) loc;
   1621   tree *GTY((skip(""))) use;
   1622 };
   1623 
   1624 struct GTY(()) tree_ssa_name {
   1625   struct tree_typed typed;
   1626 
   1627   /* _DECL wrapped by this SSA name.  */
   1628   tree var;
   1629 
   1630   /* Statement that defines this SSA name.  */
   1631   gimple *def_stmt;
   1632 
   1633   /* Value range information.  */
   1634   union ssa_name_info_type {
   1635     /* Range and aliasing info for pointers.  */
   1636     struct GTY ((tag ("0"))) ptr_info_def *ptr_info;
   1637     /* Range info for everything else.  */
   1638     struct GTY ((tag ("1"))) vrange_storage * range_info;
   1639   } GTY ((desc ("%1.typed.type ?" \
   1640 		"!POINTER_TYPE_P (TREE_TYPE ((tree)&%1)) : 2"))) info;
   1641   /* Immediate uses list for this SSA_NAME.  */
   1642   struct ssa_use_operand_t imm_uses;
   1643 };
   1644 
   1645 struct GTY(()) phi_arg_d {
   1646   /* imm_use MUST be the first element in struct because we do some
   1647      pointer arithmetic with it.  See phi_arg_index_from_use.  */
   1648   struct ssa_use_operand_t imm_use;
   1649   tree def;
   1650   location_t locus;
   1651 };
   1652 
   1653 struct GTY(()) tree_omp_clause {
   1654   struct tree_common common;
   1655   location_t locus;
   1656   enum omp_clause_code code;
   1657   union omp_clause_subcode {
   1658     enum omp_clause_default_kind   default_kind;
   1659     enum omp_clause_schedule_kind  schedule_kind;
   1660     enum omp_clause_depend_kind    depend_kind;
   1661     enum omp_clause_doacross_kind  doacross_kind;
   1662     /* See include/gomp-constants.h for enum gomp_map_kind's values.  */
   1663     unsigned int		   map_kind;
   1664     enum omp_clause_proc_bind_kind proc_bind_kind;
   1665     enum tree_code                 reduction_code;
   1666     enum omp_clause_linear_kind    linear_kind;
   1667     enum tree_code                 if_modifier;
   1668     enum omp_clause_defaultmap_kind defaultmap_kind;
   1669     enum omp_clause_bind_kind      bind_kind;
   1670     enum omp_clause_device_type_kind device_type_kind;
   1671   } GTY ((skip)) subcode;
   1672 
   1673   /* The gimplification of OMP_CLAUSE_REDUCTION_{INIT,MERGE} for omp-low's
   1674      usage.  */
   1675   gimple_seq gimple_reduction_init;
   1676   gimple_seq gimple_reduction_merge;
   1677 
   1678   tree GTY ((length ("omp_clause_num_ops[OMP_CLAUSE_CODE ((tree)&%h)]")))
   1679     ops[1];
   1680 };
   1681 
   1682 struct GTY(()) tree_block {
   1683   struct tree_base base;
   1684   tree chain;
   1685 
   1686   unsigned block_num;
   1687 
   1688   location_t locus;
   1689   location_t end_locus;
   1690 
   1691   tree vars;
   1692   vec<tree, va_gc> *nonlocalized_vars;
   1693 
   1694   tree subblocks;
   1695   tree supercontext;
   1696   tree abstract_origin;
   1697   tree fragment_origin;
   1698   tree fragment_chain;
   1699 
   1700   /* Pointer to the DWARF lexical block.  */
   1701   struct die_struct *die;
   1702 };
   1703 
   1704 struct GTY(()) tree_type_common {
   1705   struct tree_common common;
   1706   tree size;
   1707   tree size_unit;
   1708   tree attributes;
   1709   unsigned int uid;
   1710 
   1711   ENUM_BITFIELD(machine_mode) mode : MACHINE_MODE_BITSIZE;
   1712 
   1713   unsigned int precision : 16;
   1714   unsigned lang_flag_0 : 1;
   1715   unsigned lang_flag_1 : 1;
   1716   unsigned lang_flag_2 : 1;
   1717   unsigned lang_flag_3 : 1;
   1718   unsigned lang_flag_4 : 1;
   1719   unsigned lang_flag_5 : 1;
   1720   unsigned lang_flag_6 : 1;
   1721   unsigned lang_flag_7 : 1;
   1722 
   1723   /* TYPE_ALIGN in log2; this has to be large enough to hold values
   1724      of the maximum of BIGGEST_ALIGNMENT and MAX_OFILE_ALIGNMENT,
   1725      the latter being usually the larger.  For ELF it is 8<<28,
   1726      so we need to store the value 32 (not 31, as we need the zero
   1727      as well), hence six bits.  */
   1728   unsigned align : 6;
   1729   /* TYPE_STRING_FLAG for INTEGER_TYPE and ARRAY_TYPE.
   1730      TYPE_CXX_ODR_P for RECORD_TYPE and UNION_TYPE.  */
   1731   unsigned string_flag : 1;
   1732   unsigned no_force_blk_flag : 1;
   1733 
   1734   unsigned warn_if_not_align : 6;
   1735   unsigned needs_constructing_flag : 1;
   1736   unsigned transparent_aggr_flag : 1;
   1737 
   1738   unsigned contains_placeholder_bits : 2;
   1739   unsigned restrict_flag : 1;
   1740   unsigned typeless_storage : 1;
   1741   unsigned empty_flag : 1;
   1742   unsigned indivisible_p : 1;
   1743   /* TYPE_NO_NAMED_ARGS_STDARG_P for a stdarg function.
   1744      Or TYPE_INCLUDES_FLEXARRAY for RECORD_TYPE and UNION_TYPE.  */
   1745   unsigned no_named_args_stdarg_p : 1;
   1746   unsigned spare : 1;
   1747 
   1748   alias_set_type alias_set;
   1749   tree pointer_to;
   1750   tree reference_to;
   1751   union tree_type_symtab {
   1752     int GTY ((tag ("TYPE_SYMTAB_IS_ADDRESS"))) address;
   1753     struct die_struct * GTY ((tag ("TYPE_SYMTAB_IS_DIE"))) die;
   1754   } GTY ((desc ("debug_hooks->tree_type_symtab_field"))) symtab;
   1755   tree canonical;
   1756   tree next_variant;
   1757   tree main_variant;
   1758   tree context;
   1759   tree name;
   1760 };
   1761 
   1762 struct GTY(()) tree_type_with_lang_specific {
   1763   struct tree_type_common common;
   1764   /* Points to a structure whose details depend on the language in use.  */
   1765   struct lang_type *lang_specific;
   1766 };
   1767 
   1768 struct GTY(()) tree_type_non_common {
   1769   struct tree_type_with_lang_specific with_lang_specific;
   1770   tree values;
   1771   tree minval;
   1772   tree maxval;
   1773   tree lang_1;
   1774 };
   1775 
   1776 struct GTY (()) tree_binfo {
   1777   struct tree_common common;
   1778 
   1779   tree offset;
   1780   tree vtable;
   1781   tree virtuals;
   1782   tree vptr_field;
   1783   vec<tree, va_gc> *base_accesses;
   1784   tree inheritance;
   1785 
   1786   tree vtt_subvtt;
   1787   tree vtt_vptr;
   1788 
   1789   vec<tree, va_gc> base_binfos;
   1790 };
   1791 
   1792 struct GTY(()) tree_decl_minimal {
   1793   struct tree_common common;
   1794   location_t locus;
   1795   unsigned int uid;
   1796   tree name;
   1797   tree context;
   1798 };
   1799 
   1800 struct GTY(()) tree_decl_common {
   1801   struct tree_decl_minimal common;
   1802   tree size;
   1803 
   1804   ENUM_BITFIELD(machine_mode) mode : MACHINE_MODE_BITSIZE;
   1805 
   1806   unsigned nonlocal_flag : 1;
   1807   unsigned virtual_flag : 1;
   1808   unsigned ignored_flag : 1;
   1809   unsigned abstract_flag : 1;
   1810   unsigned artificial_flag : 1;
   1811   unsigned preserve_flag: 1;
   1812   unsigned debug_expr_is_from : 1;
   1813 
   1814   unsigned lang_flag_0 : 1;
   1815   unsigned lang_flag_1 : 1;
   1816   unsigned lang_flag_2 : 1;
   1817   unsigned lang_flag_3 : 1;
   1818   unsigned lang_flag_4 : 1;
   1819   unsigned lang_flag_5 : 1;
   1820   unsigned lang_flag_6 : 1;
   1821   unsigned lang_flag_7 : 1;
   1822   unsigned lang_flag_8 : 1;
   1823 
   1824   /* In VAR_DECL and PARM_DECL, this is DECL_REGISTER
   1825      In TRANSLATION_UNIT_DECL, this is TRANSLATION_UNIT_WARN_EMPTY_P.
   1826      In FIELD_DECL, this is DECL_FIELD_ABI_IGNORED.  */
   1827   unsigned decl_flag_0 : 1;
   1828   /* In FIELD_DECL, this is DECL_BIT_FIELD
   1829      In VAR_DECL and FUNCTION_DECL, this is DECL_EXTERNAL.
   1830      In TYPE_DECL, this is TYPE_DECL_SUPPRESS_DEBUG.  */
   1831   unsigned decl_flag_1 : 1;
   1832   /* In FIELD_DECL, this is DECL_NONADDRESSABLE_P
   1833      In VAR_DECL, PARM_DECL and RESULT_DECL, this is
   1834      DECL_HAS_VALUE_EXPR_P.  */
   1835   unsigned decl_flag_2 : 1;
   1836   /* In FIELD_DECL, this is DECL_PADDING_P.
   1837      In VAR_DECL, this is DECL_MERGEABLE.  */
   1838   unsigned decl_flag_3 : 1;
   1839   /* Logically, these two would go in a theoretical base shared by var and
   1840      parm decl. */
   1841   unsigned not_gimple_reg_flag : 1;
   1842   /* In VAR_DECL, PARM_DECL and RESULT_DECL, this is DECL_BY_REFERENCE.  */
   1843   unsigned decl_by_reference_flag : 1;
   1844   /* In a VAR_DECL and PARM_DECL, this is DECL_READ_P.  */
   1845   unsigned decl_read_flag : 1;
   1846   /* In a VAR_DECL or RESULT_DECL, this is DECL_NONSHAREABLE.  */
   1847   /* In a PARM_DECL, this is DECL_HIDDEN_STRING_LENGTH.  */
   1848   unsigned decl_nonshareable_flag : 1;
   1849 
   1850   /* DECL_OFFSET_ALIGN, used only for FIELD_DECLs.  */
   1851   unsigned int off_align : 6;
   1852 
   1853   /* DECL_ALIGN.  It should have the same size as TYPE_ALIGN.  */
   1854   unsigned int align : 6;
   1855 
   1856   /* DECL_WARN_IF_NOT_ALIGN.  It should have the same size as
   1857      TYPE_WARN_IF_NOT_ALIGN.  */
   1858   unsigned int warn_if_not_align : 6;
   1859 
   1860   /* In FIELD_DECL, this is DECL_NOT_FLEXARRAY.  */
   1861   unsigned int decl_not_flexarray : 1;
   1862 
   1863   /* 5 bits unused.  */
   1864 
   1865   /* UID for points-to sets, stable over copying from inlining.  */
   1866   unsigned int pt_uid;
   1867 
   1868   tree size_unit;
   1869   tree initial;
   1870   tree attributes;
   1871   tree abstract_origin;
   1872 
   1873   /* Points to a structure whose details depend on the language in use.  */
   1874   struct lang_decl *lang_specific;
   1875 };
   1876 
   1877 struct GTY(()) tree_decl_with_rtl {
   1878   struct tree_decl_common common;
   1879   rtx rtl;
   1880 };
   1881 
   1882 struct GTY(()) tree_field_decl {
   1883   struct tree_decl_common common;
   1884 
   1885   tree offset;
   1886   tree bit_field_type;
   1887   tree qualifier;
   1888   tree bit_offset;
   1889   tree fcontext;
   1890 };
   1891 
   1892 struct GTY(()) tree_label_decl {
   1893   struct tree_decl_with_rtl common;
   1894   int label_decl_uid;
   1895   int eh_landing_pad_nr;
   1896 };
   1897 
   1898 struct GTY(()) tree_result_decl {
   1899   struct tree_decl_with_rtl common;
   1900 };
   1901 
   1902 struct GTY(()) tree_const_decl {
   1903   struct tree_decl_common common;
   1904 };
   1905 
   1906 struct GTY(()) tree_parm_decl {
   1907   struct tree_decl_with_rtl common;
   1908   rtx incoming_rtl;
   1909 };
   1910 
   1911 struct GTY(()) tree_decl_with_vis {
   1912  struct tree_decl_with_rtl common;
   1913  tree assembler_name;
   1914  struct symtab_node *symtab_node;
   1915 
   1916  /* Belong to VAR_DECL exclusively.  */
   1917  unsigned defer_output : 1;
   1918  unsigned hard_register : 1;
   1919  unsigned common_flag : 1;
   1920  unsigned in_text_section : 1;
   1921  unsigned in_constant_pool : 1;
   1922  unsigned dllimport_flag : 1;
   1923  /* Don't belong to VAR_DECL exclusively.  */
   1924  unsigned weak_flag : 1;
   1925 
   1926  unsigned seen_in_bind_expr : 1;
   1927  unsigned comdat_flag : 1;
   1928  /* Used for FUNCTION_DECL, VAR_DECL and in C++ for TYPE_DECL.  */
   1929  ENUM_BITFIELD(symbol_visibility) visibility : 2;
   1930  unsigned visibility_specified : 1;
   1931 
   1932  /* Belong to FUNCTION_DECL exclusively.  */
   1933  unsigned init_priority_p : 1;
   1934  /* Used by C++ only.  Might become a generic decl flag.  */
   1935  unsigned shadowed_for_var_p : 1;
   1936  /* Belong to FUNCTION_DECL exclusively.  */
   1937  unsigned cxx_constructor : 1;
   1938  /* Belong to FUNCTION_DECL exclusively.  */
   1939  unsigned cxx_destructor : 1;
   1940  /* Belong to FUNCTION_DECL exclusively.  */
   1941  unsigned final : 1;
   1942  /* Belong to FUNCTION_DECL exclusively.  */
   1943  unsigned regdecl_flag : 1;
   1944  /* 14 unused bits. */
   1945  /* 32 more unused on 64 bit HW. */
   1946 };
   1947 
   1948 struct GTY(()) tree_var_decl {
   1949   struct tree_decl_with_vis common;
   1950 };
   1951 
   1952 struct GTY(()) tree_decl_non_common {
   1953   struct tree_decl_with_vis common;
   1954   /* Almost all FE's use this.  */
   1955   tree result;
   1956 };
   1957 
   1958 /* Classify a special function declaration type.  */
   1959 
   1960 enum function_decl_type
   1961 {
   1962   NONE,
   1963   OPERATOR_NEW,
   1964   OPERATOR_DELETE,
   1965   LAMBDA_FUNCTION
   1966 
   1967   /* 0 values left */
   1968 };
   1969 
   1970 /* FUNCTION_DECL inherits from DECL_NON_COMMON because of the use of the
   1971    arguments/result/saved_tree fields by front ends.   It was either inherit
   1972    FUNCTION_DECL from non_common, or inherit non_common from FUNCTION_DECL,
   1973    which seemed a bit strange.  */
   1974 
   1975 struct GTY(()) tree_function_decl {
   1976   struct tree_decl_non_common common;
   1977 
   1978   struct function *f;
   1979 
   1980   /* Arguments of the function.  */
   1981   tree arguments;
   1982   /* The personality function. Used for stack unwinding. */
   1983   tree personality;
   1984 
   1985   /* Function specific options that are used by this function.  */
   1986   tree function_specific_target;	/* target options */
   1987   tree function_specific_optimization;	/* optimization options */
   1988 
   1989   /* Generic function body.  */
   1990   tree saved_tree;
   1991   /* Index within a virtual table.  */
   1992   tree vindex;
   1993 
   1994   /* In a FUNCTION_DECL this is DECL_UNCHECKED_FUNCTION_CODE.  */
   1995   unsigned int function_code;
   1996 
   1997   ENUM_BITFIELD(built_in_class) built_in_class : 2;
   1998   unsigned static_ctor_flag : 1;
   1999   unsigned static_dtor_flag : 1;
   2000   unsigned uninlinable : 1;
   2001   unsigned possibly_inlined : 1;
   2002   unsigned novops_flag : 1;
   2003   unsigned returns_twice_flag : 1;
   2004 
   2005   unsigned malloc_flag : 1;
   2006   unsigned declared_inline_flag : 1;
   2007   unsigned no_inline_warning_flag : 1;
   2008   unsigned no_instrument_function_entry_exit : 1;
   2009   unsigned no_limit_stack : 1;
   2010   unsigned disregard_inline_limits : 1;
   2011   unsigned pure_flag : 1;
   2012   unsigned looping_const_or_pure_flag : 1;
   2013 
   2014   /* Align the bitfield to boundary of a byte.  */
   2015   ENUM_BITFIELD(function_decl_type) decl_type: 2;
   2016   unsigned has_debug_args_flag : 1;
   2017   unsigned versioned_function : 1;
   2018   unsigned replaceable_operator : 1;
   2019 
   2020   /* 11 bits left for future expansion.  */
   2021   /* 32 bits on 64-bit HW.  */
   2022 };
   2023 
   2024 struct GTY(()) tree_translation_unit_decl {
   2025   struct tree_decl_common common;
   2026   /* Source language of this translation unit.  Used for DWARF output.  */
   2027   const char *language;
   2028   /* TODO: Non-optimization used to build this translation unit.  */
   2029   /* TODO: Root of a partial DWARF tree for global types and decls.  */
   2030 };
   2031 
   2032 struct GTY(()) tree_type_decl {
   2033   struct tree_decl_non_common common;
   2034 
   2035 };
   2036 
   2037 struct GTY ((chain_next ("%h.next"), chain_prev ("%h.prev"))) tree_statement_list_node
   2038  {
   2039   struct tree_statement_list_node *prev;
   2040   struct tree_statement_list_node *next;
   2041   tree stmt;
   2042 };
   2043 
   2044 struct GTY(()) tree_statement_list
   2045  {
   2046   struct tree_typed typed;
   2047   struct tree_statement_list_node *head;
   2048   struct tree_statement_list_node *tail;
   2049 };
   2050 
   2051 
   2052 /* Optimization options used by a function.  */
   2053 
   2054 struct GTY(()) tree_optimization_option {
   2055   struct tree_base base;
   2056 
   2057   /* The optimization options used by the user.  */
   2058   struct cl_optimization *opts;
   2059 
   2060   /* Target optabs for this set of optimization options.  This is of
   2061      type `struct target_optabs *'.  */
   2062   void *GTY ((atomic)) optabs;
   2063 
   2064   /* The value of this_target_optabs against which the optabs above were
   2065      generated.  */
   2066   struct target_optabs *GTY ((skip)) base_optabs;
   2067 };
   2068 
   2069 /* Forward declaration, defined in target-globals.h.  */
   2070 
   2071 class GTY(()) target_globals;
   2072 
   2073 /* Target options used by a function.  */
   2074 
   2075 struct GTY(()) tree_target_option {
   2076   struct tree_base base;
   2077 
   2078   /* Target globals for the corresponding target option.  */
   2079   class target_globals *globals;
   2080 
   2081   /* The optimization options used by the user.  */
   2082   struct cl_target_option *opts;
   2083 };
   2084 
   2085 /* Define the overall contents of a tree node.
   2086    It may be any of the structures declared above
   2087    for various types of node.  */
   2088 union GTY ((ptr_alias (union lang_tree_node),
   2089 	    desc ("tree_node_structure (&%h)"), variable_size)) tree_node {
   2090   struct tree_base GTY ((tag ("TS_BASE"))) base;
   2091   struct tree_typed GTY ((tag ("TS_TYPED"))) typed;
   2092   struct tree_common GTY ((tag ("TS_COMMON"))) common;
   2093   struct tree_int_cst GTY ((tag ("TS_INT_CST"))) int_cst;
   2094   struct tree_poly_int_cst GTY ((tag ("TS_POLY_INT_CST"))) poly_int_cst;
   2095   struct tree_real_cst GTY ((tag ("TS_REAL_CST"))) real_cst;
   2096   struct tree_fixed_cst GTY ((tag ("TS_FIXED_CST"))) fixed_cst;
   2097   struct tree_vector GTY ((tag ("TS_VECTOR"))) vector;
   2098   struct tree_string GTY ((tag ("TS_STRING"))) string;
   2099   struct tree_complex GTY ((tag ("TS_COMPLEX"))) complex;
   2100   struct tree_identifier GTY ((tag ("TS_IDENTIFIER"))) identifier;
   2101   struct tree_decl_minimal GTY((tag ("TS_DECL_MINIMAL"))) decl_minimal;
   2102   struct tree_decl_common GTY ((tag ("TS_DECL_COMMON"))) decl_common;
   2103   struct tree_decl_with_rtl GTY ((tag ("TS_DECL_WRTL"))) decl_with_rtl;
   2104   struct tree_decl_non_common  GTY ((tag ("TS_DECL_NON_COMMON")))
   2105     decl_non_common;
   2106   struct tree_parm_decl  GTY  ((tag ("TS_PARM_DECL"))) parm_decl;
   2107   struct tree_decl_with_vis GTY ((tag ("TS_DECL_WITH_VIS"))) decl_with_vis;
   2108   struct tree_var_decl GTY ((tag ("TS_VAR_DECL"))) var_decl;
   2109   struct tree_field_decl GTY ((tag ("TS_FIELD_DECL"))) field_decl;
   2110   struct tree_label_decl GTY ((tag ("TS_LABEL_DECL"))) label_decl;
   2111   struct tree_result_decl GTY ((tag ("TS_RESULT_DECL"))) result_decl;
   2112   struct tree_const_decl GTY ((tag ("TS_CONST_DECL"))) const_decl;
   2113   struct tree_type_decl GTY ((tag ("TS_TYPE_DECL"))) type_decl;
   2114   struct tree_function_decl GTY ((tag ("TS_FUNCTION_DECL"))) function_decl;
   2115   struct tree_translation_unit_decl GTY ((tag ("TS_TRANSLATION_UNIT_DECL")))
   2116     translation_unit_decl;
   2117   struct tree_type_common GTY ((tag ("TS_TYPE_COMMON"))) type_common;
   2118   struct tree_type_with_lang_specific GTY ((tag ("TS_TYPE_WITH_LANG_SPECIFIC")))
   2119     type_with_lang_specific;
   2120   struct tree_type_non_common GTY ((tag ("TS_TYPE_NON_COMMON")))
   2121     type_non_common;
   2122   struct tree_list GTY ((tag ("TS_LIST"))) list;
   2123   struct tree_vec GTY ((tag ("TS_VEC"))) vec;
   2124   struct tree_exp GTY ((tag ("TS_EXP"))) exp;
   2125   struct tree_ssa_name GTY ((tag ("TS_SSA_NAME"))) ssa_name;
   2126   struct tree_block GTY ((tag ("TS_BLOCK"))) block;
   2127   struct tree_binfo GTY ((tag ("TS_BINFO"))) binfo;
   2128   struct tree_statement_list GTY ((tag ("TS_STATEMENT_LIST"))) stmt_list;
   2129   struct tree_constructor GTY ((tag ("TS_CONSTRUCTOR"))) constructor;
   2130   struct tree_omp_clause GTY ((tag ("TS_OMP_CLAUSE"))) omp_clause;
   2131   struct tree_optimization_option GTY ((tag ("TS_OPTIMIZATION"))) optimization;
   2132   struct tree_target_option GTY ((tag ("TS_TARGET_OPTION"))) target_option;
   2133 };
   2134 
   2135 /* Structure describing an attribute and a function to handle it.  */
   2136 struct attribute_spec {
   2137   /* The name of the attribute (without any leading or trailing __),
   2138      or NULL to mark the end of a table of attributes.  */
   2139   const char *name;
   2140   /* The minimum length of the list of arguments of the attribute.  */
   2141   int min_length;
   2142   /* The maximum length of the list of arguments of the attribute
   2143      (-1 for no maximum).  It can also be -2 for fake attributes
   2144      created for the sake of -Wno-attributes; in that case, we
   2145      should skip the balanced token sequence when parsing the attribute.  */
   2146   int max_length;
   2147   /* Whether this attribute requires a DECL.  If it does, it will be passed
   2148      from types of DECLs, function return types and array element types to
   2149      the DECLs, function types and array types respectively; but when
   2150      applied to a type in any other circumstances, it will be ignored with
   2151      a warning.  (If greater control is desired for a given attribute,
   2152      this should be false, and the flags argument to the handler may be
   2153      used to gain greater control in that case.)  */
   2154   bool decl_required;
   2155   /* Whether this attribute requires a type.  If it does, it will be passed
   2156      from a DECL to the type of that DECL.  */
   2157   bool type_required;
   2158   /* Whether this attribute requires a function (or method) type.  If it does,
   2159      it will be passed from a function pointer type to the target type,
   2160      and from a function return type (which is not itself a function
   2161      pointer type) to the function type.  */
   2162   bool function_type_required;
   2163   /* Specifies if attribute affects type's identity.  */
   2164   bool affects_type_identity;
   2165   /* Function to handle this attribute.  NODE points to a tree[3] array,
   2166      where node[0] is the node to which the attribute is to be applied;
   2167      node[1] is the last pushed/merged declaration if one exists, and node[2]
   2168      may be the declaration for node[0].  If a DECL, it should be modified in
   2169      place; if a TYPE, a copy should be created.  NAME is the canonicalized
   2170      name of the attribute i.e. without any leading or trailing underscores.
   2171      ARGS is the TREE_LIST of the arguments (which may be NULL).  FLAGS gives
   2172      further information about the context of the attribute.  Afterwards, the
   2173      attributes will be added to the DECL_ATTRIBUTES or TYPE_ATTRIBUTES, as
   2174      appropriate, unless *NO_ADD_ATTRS is set to true (which should be done on
   2175      error, as well as in any other cases when the attributes should not be
   2176      added to the DECL or TYPE).  Depending on FLAGS, any attributes to be
   2177      applied to another type or DECL later may be returned;
   2178      otherwise the return value should be NULL_TREE.  This pointer may be
   2179      NULL if no special handling is required beyond the checks implied
   2180      by the rest of this structure.  */
   2181   tree (*handler) (tree *node, tree name, tree args,
   2182 		   int flags, bool *no_add_attrs);
   2183 
   2184   /* Specifies the name of an attribute that's mutually exclusive with
   2185      this one, and whether the relationship applies to the function,
   2186      variable, or type form of the attribute.  */
   2187   struct exclusions {
   2188     const char *name;
   2189     bool function;
   2190     bool variable;
   2191     bool type;
   2192   };
   2193 
   2194   /* An array of attribute exclusions describing names of other attributes
   2195      that this attribute is mutually exclusive with.  */
   2196   const exclusions *exclude;
   2197 };
   2198 
   2199 /* These functions allow a front-end to perform a manual layout of a
   2200    RECORD_TYPE.  (For instance, if the placement of subsequent fields
   2201    depends on the placement of fields so far.)  Begin by calling
   2202    start_record_layout.  Then, call place_field for each of the
   2203    fields.  Then, call finish_record_layout.  See layout_type for the
   2204    default way in which these functions are used.  */
   2205 typedef struct record_layout_info_s {
   2206   /* The RECORD_TYPE that we are laying out.  */
   2207   tree t;
   2208   /* The offset into the record so far, in bytes, not including bits in
   2209      BITPOS.  */
   2210   tree offset;
   2211   /* The last known alignment of SIZE.  */
   2212   unsigned int offset_align;
   2213   /* The bit position within the last OFFSET_ALIGN bits, in bits.  */
   2214   tree bitpos;
   2215   /* The alignment of the record so far, in bits.  */
   2216   unsigned int record_align;
   2217   /* The alignment of the record so far, ignoring #pragma pack and
   2218      __attribute__ ((packed)), in bits.  */
   2219   unsigned int unpacked_align;
   2220   /* The previous field laid out.  */
   2221   tree prev_field;
   2222   /* The static variables (i.e., class variables, as opposed to
   2223      instance variables) encountered in T.  */
   2224   vec<tree, va_gc> *pending_statics;
   2225   /* Bits remaining in the current alignment group */
   2226   int remaining_in_alignment;
   2227   /* True if we've seen a packed field that didn't have normal
   2228      alignment anyway.  */
   2229   int packed_maybe_necessary;
   2230 } *record_layout_info;
   2231 
   2232 /* Iterator for going through the function arguments.  */
   2233 struct function_args_iterator {
   2234   tree next;			/* TREE_LIST pointing to the next argument */
   2235 };
   2236 
   2237 /* Structures to map from a tree to another tree.  */
   2238 struct GTY(()) tree_map_base {
   2239   tree from;
   2240 };
   2241 
   2242 /* Map from a tree to another tree.  */
   2243 
   2244 struct GTY((for_user)) tree_map {
   2245   struct tree_map_base base;
   2246   unsigned int hash;
   2247   tree to;
   2248 };
   2249 
   2250 /* Map from a decl tree to another tree.  */
   2251 struct GTY((for_user)) tree_decl_map {
   2252   struct tree_map_base base;
   2253   tree to;
   2254 };
   2255 
   2256 /* Map from a tree to an int.  */
   2257 struct GTY((for_user)) tree_int_map {
   2258   struct tree_map_base base;
   2259   unsigned int to;
   2260 };
   2261 
   2262 /* Map from a decl tree to a tree vector.  */
   2263 struct GTY((for_user)) tree_vec_map {
   2264   struct tree_map_base base;
   2265   vec<tree, va_gc> *to;
   2266 };
   2267 
   2268 /* Abstract iterators for CALL_EXPRs.  These static inline definitions
   2269    have to go towards the end of tree.h so that union tree_node is fully
   2270    defined by this point.  */
   2271 
   2272 /* Structure containing iterator state.  */
   2273 struct call_expr_arg_iterator {
   2274   tree t;	/* the call_expr */
   2275   int n;	/* argument count */
   2276   int i;	/* next argument index */
   2277 };
   2278 
   2279 struct const_call_expr_arg_iterator {
   2280   const_tree t;	/* the call_expr */
   2281   int n;	/* argument count */
   2282   int i;	/* next argument index */
   2283 };
   2284 
   2285 /* The builtin_info structure holds the FUNCTION_DECL of the standard builtin
   2286    function, and flags.  */
   2287 struct GTY(()) builtin_info_type {
   2288   tree decl;
   2289   /* Whether the user can use <xxx> instead of explicitly using calls
   2290      to __builtin_<xxx>.  */
   2291   unsigned implicit_p : 1;
   2292   /* Whether the user has provided a declaration of <xxx>.  */
   2293   unsigned declared_p : 1;
   2294 };
   2295 
   2296 /* Information about a _FloatN or _FloatNx type that may be
   2297    supported.  */
   2298 struct floatn_type_info {
   2299   /* The number N in the type name.  */
   2300   int n;
   2301   /* Whether it is an extended type _FloatNx (true) or an interchange
   2302      type (false).  */
   2303   bool extended;
   2304 };
   2305 
   2306 
   2307 /*---------------------------------------------------------------------------
   2308                                 Global variables
   2309 ---------------------------------------------------------------------------*/
   2310 /* Matrix describing the structures contained in a given tree code.  */
   2311 extern bool tree_contains_struct[MAX_TREE_CODES][64];
   2312 
   2313 /* Class of tree given its code.  */
   2314 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
   2315 #define END_OF_BASE_TREE_CODES tcc_exceptional,
   2316 
   2317 #if __cpp_inline_variables < 201606L
   2318 template <int N>
   2319 struct tree_code_type_tmpl {
   2320   static constexpr enum tree_code_class tree_code_type[] = {
   2321 #include "all-tree.def"
   2322   };
   2323 };
   2324 
   2325 template <int N>
   2326 constexpr enum tree_code_class tree_code_type_tmpl<N>::tree_code_type[];
   2327 #else
   2328 constexpr inline enum tree_code_class tree_code_type[] = {
   2329 #include "all-tree.def"
   2330 };
   2331 #endif
   2332 
   2333 #undef DEFTREECODE
   2334 #undef END_OF_BASE_TREE_CODES
   2335 
   2336 /* Each tree code class has an associated string representation.
   2337    These must correspond to the tree_code_class entries.  */
   2338 extern const char *const tree_code_class_strings[];
   2339 
   2340 /* Number of argument-words in each kind of tree-node.  */
   2341 
   2342 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
   2343 #define END_OF_BASE_TREE_CODES 0,
   2344 
   2345 #if __cpp_inline_variables < 201606L
   2346 template <int N>
   2347 struct tree_code_length_tmpl {
   2348   static constexpr unsigned char tree_code_length[] = {
   2349 #include "all-tree.def"
   2350   };
   2351 };
   2352 
   2353 template <int N>
   2354 constexpr unsigned char tree_code_length_tmpl<N>::tree_code_length[];
   2355 #else
   2356 constexpr inline unsigned char tree_code_length[] = {
   2357 #include "all-tree.def"
   2358 };
   2359 #endif
   2360 
   2361 #undef DEFTREECODE
   2362 #undef END_OF_BASE_TREE_CODES
   2363 
   2364 /* Vector of all alias pairs for global symbols.  */
   2365 extern GTY(()) vec<alias_pair, va_gc> *alias_pairs;
   2366 
   2367 /* Names of all the built_in classes.  */
   2368 extern const char *const built_in_class_names[BUILT_IN_LAST];
   2369 
   2370 /* Names of all the built_in functions.  */
   2371 extern const char * built_in_names[(int) END_BUILTINS];
   2372 
   2373 /* Number of operands and names for each OMP_CLAUSE node.  */
   2374 extern unsigned const char omp_clause_num_ops[];
   2375 extern const char * const omp_clause_code_name[];
   2376 extern const char *user_omp_clause_code_name (tree, bool);
   2377 
   2378 /* A vector of all translation-units.  */
   2379 extern GTY (()) vec<tree, va_gc> *all_translation_units;
   2380 
   2381 /* Vector of standard trees used by the C compiler.  */
   2382 extern GTY(()) tree global_trees[TI_MAX];
   2383 
   2384 /* The standard C integer types.  Use integer_type_kind to index into
   2385    this array.  */
   2386 extern GTY(()) tree integer_types[itk_none];
   2387 
   2388 /* Types used to represent sizes.  */
   2389 extern GTY(()) tree sizetype_tab[(int) stk_type_kind_last];
   2390 
   2391 /* Arrays for keeping track of tree node statistics.  */
   2392 extern uint64_t tree_node_counts[];
   2393 extern uint64_t tree_node_sizes[];
   2394 
   2395 /* True if we are in gimple form and the actions of the folders need to
   2396    be restricted.  False if we are not in gimple form and folding is not
   2397    restricted to creating gimple expressions.  */
   2398 extern bool in_gimple_form;
   2399 
   2400 /* Functional interface to the builtin functions.  */
   2401 extern GTY(()) builtin_info_type builtin_info[(int)END_BUILTINS];
   2402 
   2403 /* If nonzero, an upper limit on alignment of structure fields, in bits,  */
   2404 extern unsigned int maximum_field_alignment;
   2405 
   2406 /* Points to the FUNCTION_DECL of the function whose body we are reading.  */
   2407 extern GTY(()) tree current_function_decl;
   2408 
   2409 /* Nonzero means a FUNC_BEGIN label was emitted.  */
   2410 extern GTY(()) const char * current_function_func_begin_label;
   2411 
   2412 /* Information about the _FloatN and _FloatNx types.  */
   2413 extern const floatn_type_info floatn_nx_types[NUM_FLOATN_NX_TYPES];
   2414 
   2415 #endif  // GCC_TREE_CORE_H
   2416