GCC Middle and Back End API Reference
tree-core.h
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1 /* Core data structures for the 'tree' type.
2  Copyright (C) 1989-2013 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10 
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19 
20 #ifndef GCC_TREE_CORE_H
21 #define GCC_TREE_CORE_H
22 
23 #include "hashtab.h"
24 #include "machmode.h"
25 #include "input.h"
26 #include "statistics.h"
27 #include "vec.h"
28 #include "double-int.h"
29 #include "real.h"
30 #include "fixed-value.h"
31 #include "alias.h"
32 #include "flags.h"
33 #include "symtab.h"
34 
35 /* This file contains all the data structures that define the 'tree' type.
36  There are no accessor macros nor functions in this file. Only the
37  basic data structures, extern declarations and type definitions. */
38 
39 /*---------------------------------------------------------------------------
40  Forward type declarations. Mostly to avoid including unnecessary headers
41 ---------------------------------------------------------------------------*/
42 struct function;
43 struct real_value;
44 struct fixed_value;
45 struct ptr_info_def;
46 struct range_info_def;
47 struct die_struct;
48 struct pointer_set_t;
49 
50 
51 /*---------------------------------------------------------------------------
52  #defined constants
53 ---------------------------------------------------------------------------*/
54 /* Nonzero if this is a call to a function whose return value depends
55  solely on its arguments, has no side effects, and does not read
56  global memory. This corresponds to TREE_READONLY for function
57  decls. */
58 #define ECF_CONST (1 << 0)
59 
60 /* Nonzero if this is a call to "pure" function (like const function,
61  but may read memory. This corresponds to DECL_PURE_P for function
62  decls. */
63 #define ECF_PURE (1 << 1)
64 
65 /* Nonzero if this is ECF_CONST or ECF_PURE but cannot be proven to no
66  infinite loop. This corresponds to DECL_LOOPING_CONST_OR_PURE_P
67  for function decls.*/
68 #define ECF_LOOPING_CONST_OR_PURE (1 << 2)
69 
70 /* Nonzero if this call will never return. */
71 #define ECF_NORETURN (1 << 3)
72 
73 /* Nonzero if this is a call to malloc or a related function. */
74 #define ECF_MALLOC (1 << 4)
75 
76 /* Nonzero if it is plausible that this is a call to alloca. */
77 #define ECF_MAY_BE_ALLOCA (1 << 5)
78 
79 /* Nonzero if this is a call to a function that won't throw an exception. */
80 #define ECF_NOTHROW (1 << 6)
81 
82 /* Nonzero if this is a call to setjmp or a related function. */
83 #define ECF_RETURNS_TWICE (1 << 7)
84 
85 /* Nonzero if this call replaces the current stack frame. */
86 #define ECF_SIBCALL (1 << 8)
87 
88 /* Function does not read or write memory (but may have side effects, so
89  it does not necessarily fit ECF_CONST). */
90 #define ECF_NOVOPS (1 << 9)
91 
92 /* The function does not lead to calls within current function unit. */
93 #define ECF_LEAF (1 << 10)
94 
95 /* Nonzero if this call does not affect transactions. */
96 #define ECF_TM_PURE (1 << 11)
97 
98 /* Nonzero if this call is into the transaction runtime library. */
99 #define ECF_TM_BUILTIN (1 << 12)
100 
101 /* Call argument flags. */
102 /* Nonzero if the argument is not dereferenced recursively, thus only
103  directly reachable memory is read or written. */
104 #define EAF_DIRECT (1 << 0)
105 
106 /* Nonzero if memory reached by the argument is not clobbered. */
107 #define EAF_NOCLOBBER (1 << 1)
108 
109 /* Nonzero if the argument does not escape. */
110 #define EAF_NOESCAPE (1 << 2)
111 
112 /* Nonzero if the argument is not used by the function. */
113 #define EAF_UNUSED (1 << 3)
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"
139 };
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)])
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,
157  BUILT_IN_MD,
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,
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). */
218 
219  /* OpenMP clause: shared (variable_list). */
221 
222  /* OpenMP clause: firstprivate (variable_list). */
225  /* OpenMP clause: lastprivate (variable_list). */
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}. */
236 
237  /* OpenMP clause: copyin (variable_list). */
240  /* OpenMP clause: copyprivate (variable_list). */
242 
243  /* OpenMP clause: linear (variable-list[:linear-step]). */
246  /* OpenMP clause: aligned (variable-list[:alignment]). */
248 
249  /* OpenMP clause: depend ({in,out,inout}:variable-list). */
251 
252  /* OpenMP clause: uniform (argument-list). */
254 
255  /* OpenMP clause: from (variable-list). */
258  /* OpenMP clause: to (variable-list). */
260 
261  /* OpenMP clause: map ({alloc:,to:,from:,tofrom:,}variable-list). */
263 
264  /* Internal clause: temporary for combined loops expansion. */
266 
267  /* OpenMP clause: if (scalar-expression). */
269 
270  /* OpenMP clause: num_threads (integer-expression). */
272 
273  /* OpenMP clause: schedule. */
276  /* OpenMP clause: nowait. */
279  /* OpenMP clause: ordered. */
281 
282  /* OpenMP clause: default. */
284 
285  /* OpenMP clause: collapse (constant-integer-expression). */
288  /* OpenMP clause: untied. */
291  /* OpenMP clause: final (scalar-expression). */
293 
294  /* OpenMP clause: mergeable. */
296 
297  /* OpenMP clause: device (integer-expression). */
300  /* OpenMP clause: dist_schedule (static[:chunk-size]). */
302 
303  /* OpenMP clause: inbranch. */
305 
306  /* OpenMP clause: notinbranch. */
309  /* OpenMP clause: num_teams(integer-expression). */
312  /* OpenMP clause: thread_limit(integer-expression). */
314 
315  /* OpenMP clause: proc_bind ({master,close,spread}). */
317 
318  /* OpenMP clause: safelen (constant-integer-expression). */
320 
321  /* OpenMP clause: simdlen (constant-integer-expression). */
324  /* OpenMP clause: for. */
326 
327  /* OpenMP clause: parallel. */
329 
330  /* OpenMP clause: sections. */
333  /* OpenMP clause: taskgroup. */
336  /* Internally used only clause, holding SIMD uid. */
338 };
340 #undef DEFTREESTRUCT
341 #define DEFTREESTRUCT(ENUM, NAME) ENUM,
343 #include "treestruct.def"
345 };
346 #undef DEFTREESTRUCT
354 };
362 };
364 /* There is a TYPE_QUAL value for each type qualifier. They can be
365  combined by bitwise-or to form the complete set of qualifiers for a
366  type. */
368  TYPE_UNQUALIFIED = 0x0,
369  TYPE_QUAL_CONST = 0x1,
370  TYPE_QUAL_VOLATILE = 0x2,
372 };
374 /* Enumerate visibility settings. */
375 #ifndef SYMBOL_VISIBILITY_DEFINED
376 #define SYMBOL_VISIBILITY_DEFINED
377 enum symbol_visibility {
382 };
383 #endif // SYMBOL_VISIBILITY_DEFINED
384 
385 /* Standard named or nameless data types of the C compiler. */
386 enum tree_index {
393 
409 
410  TI_SIZE_ZERO,
412 
417  TI_PUBLIC,
418  TI_PROTECTED,
419  TI_PRIVATE,
420 
428 
437 
438  TI_VOID_TYPE,
439  TI_PTR_TYPE,
441  TI_SIZE_TYPE,
450 
452 
459 
461 
497  TI_HQ_TYPE,
500  TI_TQ_TYPE,
505  TI_UTQ_TYPE,
540  TI_MAX
541 };
543 /* An enumeration of the standard C integer types. These must be
544  ordered so that shorter types appear before longer ones, and so
545  that signed types appear before unsigned ones, for the correct
546  functioning of interpret_integer() in c-lex.c. */
562 };
564 /* A pointer-to-function member type looks like:
566  struct {
567  __P __pfn;
568  ptrdiff_t __delta;
569  };
571  If __pfn is NULL, it is a NULL pointer-to-member-function.
573  (Because the vtable is always the first thing in the object, we
574  don't need its offset.) If the function is virtual, then PFN is
575  one plus twice the index into the vtable; otherwise, it is just a
576  pointer to the function.
578  Unfortunately, using the lowest bit of PFN doesn't work in
579  architectures that don't impose alignment requirements on function
580  addresses, or that use the lowest bit to tell one ISA from another,
581  for example. For such architectures, we use the lowest bit of
582  DELTA instead of the lowest bit of the PFN, and DELTA will be
583  multiplied by 2. */
587 };
589 /* Flags that may be passed in the third argument of decl_attributes, and
590  to handler functions for attributes. */
592  /* The type passed in is the type of a DECL, and any attributes that
593  should be passed in again to be applied to the DECL rather than the
594  type should be returned. */
596  /* The type passed in is a function return type, and any attributes that
597  should be passed in again to be applied to the function type rather
598  than the return type should be returned. */
600  /* The type passed in is an array element type, and any attributes that
601  should be passed in again to be applied to the array type rather
602  than the element type should be returned. */
604  /* The type passed in is a structure, union or enumeration type being
605  created, and should be modified in place. */
607  /* The attributes are being applied by default to a library function whose
608  name indicates known behavior, and should be silently ignored if they
609  are not in fact compatible with the function type. */
611  /* A given attribute has been parsed as a C++-11 attribute. */
613 };
615 /* Types used to represent sizes. */
616 enum size_type_kind {
617  stk_sizetype, /* Normal representation of sizes in bytes. */
618  stk_ssizetype, /* Signed representation of sizes in bytes. */
619  stk_bitsizetype, /* Normal representation of sizes in bits. */
620  stk_sbitsizetype, /* Signed representation of sizes in bits. */
622 };
623 
624 enum operand_equal_flag {
628 };
630 /* Enum and arrays used for tree allocation stats.
631  Keep in sync with tree.c:tree_node_kind_names. */
640  id_kind,
641  vec_kind,
642  binfo_kind,
644  constr_kind,
645  x_kind,
646  lang_decl,
647  lang_type,
649  all_kinds
650 };
651 
652 enum annot_expr_kind {
654 };
655 
656 
657 /*---------------------------------------------------------------------------
658  Type definitions
659 ---------------------------------------------------------------------------*/
660 /* When processing aliases at the symbol table level, we need the
661  declaration of target. For this reason we need to queue aliases and
662  process them after all declarations has been produced. */
663 typedef struct GTY(()) alias_pair {
665  tree target;
666 } alias_pair;
667 
668 /* An initialization priority. */
669 typedef unsigned short priority_type;
670 
671 /* The type of a callback function for walking over tree structure. */
672 typedef tree (*walk_tree_fn) (tree *, int *, void *);
673 
674 /* The type of a callback function that represents a custom walk_tree. */
675 typedef tree (*walk_tree_lh) (tree *, int *, tree (*) (tree *, int *, void *),
676  void *, struct pointer_set_t*);
677 
678 
679 /*---------------------------------------------------------------------------
680  Main data structures
681 ---------------------------------------------------------------------------*/
682 /* A tree node can represent a data type, a variable, an expression
683  or a statement. Each node has a TREE_CODE which says what kind of
684  thing it represents. Some common codes are:
685  INTEGER_TYPE -- represents a type of integers.
686  ARRAY_TYPE -- represents a type of pointer.
687  VAR_DECL -- represents a declared variable.
688  INTEGER_CST -- represents a constant integer value.
689  PLUS_EXPR -- represents a sum (an expression).
691  As for the contents of a tree node: there are some fields
692  that all nodes share. Each TREE_CODE has various special-purpose
693  fields as well. The fields of a node are never accessed directly,
694  always through accessor macros. */
696 /* Every kind of tree node starts with this structure,
697  so all nodes have these fields.
699  See the accessor macros, defined below, for documentation of the
700  fields, and the table below which connects the fields and the
701  accessor macros. */
702 
703 struct GTY(()) tree_base {
704  ENUM_BITFIELD(tree_code) code : 16;
706  unsigned side_effects_flag : 1;
707  unsigned constant_flag : 1;
708  unsigned addressable_flag : 1;
709  unsigned volatile_flag : 1;
710  unsigned readonly_flag : 1;
711  unsigned asm_written_flag: 1;
712  unsigned nowarning_flag : 1;
713  unsigned visited : 1;
715  unsigned used_flag : 1;
716  unsigned nothrow_flag : 1;
717  unsigned static_flag : 1;
718  unsigned public_flag : 1;
719  unsigned private_flag : 1;
720  unsigned protected_flag : 1;
721  unsigned deprecated_flag : 1;
722  unsigned default_def_flag : 1;
724  union {
725  /* The bits in the following structure should only be used with
726  accessor macros that constrain inputs with tree checking. */
727  struct {
728  unsigned lang_flag_0 : 1;
729  unsigned lang_flag_1 : 1;
730  unsigned lang_flag_2 : 1;
731  unsigned lang_flag_3 : 1;
732  unsigned lang_flag_4 : 1;
733  unsigned lang_flag_5 : 1;
734  unsigned lang_flag_6 : 1;
735  unsigned saturating_flag : 1;
737  unsigned unsigned_flag : 1;
738  unsigned packed_flag : 1;
739  unsigned user_align : 1;
740  unsigned nameless_flag : 1;
741  unsigned spare0 : 4;
742 
743  unsigned spare1 : 8;
744 
745  /* This field is only used with TREE_TYPE nodes; the only reason it is
746  present in tree_base instead of tree_type is to save space. The size
747  of the field must be large enough to hold addr_space_t values. */
748  unsigned address_space : 8;
749  } bits;
750  /* The following fields are present in tree_base to save space. The
751  nodes using them do not require any of the flags above and so can
752  make better use of the 4-byte sized word. */
753  /* VEC length. This field is only used with TREE_VEC. */
754  int length;
755  /* SSA version number. This field is only used with SSA_NAME. */
756  unsigned int version;
757  } GTY((skip(""))) u;
758 };
760 /* The following table lists the uses of each of the above flags and
761  for which types of nodes they are defined.
762 
763  addressable_flag:
764 
765  TREE_ADDRESSABLE in
766  VAR_DECL, PARM_DECL, RESULT_DECL, FUNCTION_DECL, LABEL_DECL
767  SSA_NAME
768  all types
769  CONSTRUCTOR, IDENTIFIER_NODE
770  STMT_EXPR
771 
772  CALL_EXPR_TAILCALL in
773  CALL_EXPR
774 
775  CASE_LOW_SEEN in
776  CASE_LABEL_EXPR
777 
778  PREDICT_EXPR_OUTCOME in
779  PREDICT_EXPR
780 
781  static_flag:
782 
783  TREE_STATIC in
784  VAR_DECL, FUNCTION_DECL
785  CONSTRUCTOR
786 
787  TREE_NO_TRAMPOLINE in
788  ADDR_EXPR
789 
790  BINFO_VIRTUAL_P in
791  TREE_BINFO
792 
793  TREE_SYMBOL_REFERENCED in
794  IDENTIFIER_NODE
795 
796  CLEANUP_EH_ONLY in
797  TARGET_EXPR, WITH_CLEANUP_EXPR
799  TRY_CATCH_IS_CLEANUP in
800  TRY_CATCH_EXPR
802  ASM_INPUT_P in
803  ASM_EXPR
805  TYPE_REF_CAN_ALIAS_ALL in
806  POINTER_TYPE, REFERENCE_TYPE
808  CASE_HIGH_SEEN in
809  CASE_LABEL_EXPR
811  ENUM_IS_SCOPED in
812  ENUMERAL_TYPE
814  TRANSACTION_EXPR_OUTER in
815  TRANSACTION_EXPR
817  public_flag:
818 
819  TREE_OVERFLOW in
820  INTEGER_CST, REAL_CST, COMPLEX_CST, VECTOR_CST
821 
822  TREE_PUBLIC in
823  VAR_DECL, FUNCTION_DECL
824  IDENTIFIER_NODE
826  ASM_VOLATILE_P in
827  ASM_EXPR
829  CALL_EXPR_VA_ARG_PACK in
830  CALL_EXPR
831 
832  TYPE_CACHED_VALUES_P in
833  all types
835  SAVE_EXPR_RESOLVED_P in
836  SAVE_EXPR
837 
838  OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE in
839  OMP_CLAUSE_LASTPRIVATE
840 
841  OMP_CLAUSE_PRIVATE_DEBUG in
842  OMP_CLAUSE_PRIVATE
843 
844  OMP_CLAUSE_LINEAR_NO_COPYIN in
845  OMP_CLAUSE_LINEAR
846 
847  OMP_CLAUSE_MAP_ZERO_BIAS_ARRAY_SECTION in
848  OMP_CLAUSE_MAP
849 
850  OMP_CLAUSE_REDUCTION_OMP_ORIG_REF in
851  OMP_CLAUSE_REDUCTION
853  TRANSACTION_EXPR_RELAXED in
854  TRANSACTION_EXPR
856  private_flag:
857 
858  TREE_PRIVATE in
859  all decls
860 
861  CALL_EXPR_RETURN_SLOT_OPT in
862  CALL_EXPR
863 
864  OMP_SECTION_LAST in
865  OMP_SECTION
866 
867  OMP_PARALLEL_COMBINED in
868  OMP_PARALLEL
869 
870  OMP_ATOMIC_SEQ_CST in
871  OMP_ATOMIC*
872 
873  OMP_CLAUSE_PRIVATE_OUTER_REF in
874  OMP_CLAUSE_PRIVATE
875 
876  OMP_CLAUSE_LINEAR_NO_COPYOUT in
877  OMP_CLAUSE_LINEAR
878 
879  TYPE_REF_IS_RVALUE in
880  REFERENCE_TYPE
881 
882  ENUM_IS_OPAQUE in
883  ENUMERAL_TYPE
884 
885  protected_flag:
886 
887  TREE_PROTECTED in
888  BLOCK
889  all decls
890 
891  CALL_FROM_THUNK_P and
892  CALL_ALLOCA_FOR_VAR_P in
893  CALL_EXPR
894 
895  side_effects_flag:
896 
897  TREE_SIDE_EFFECTS in
898  all expressions
899  all decls
900  all constants
901 
902  FORCED_LABEL in
903  LABEL_DECL
904 
905  volatile_flag:
906 
907  TREE_THIS_VOLATILE in
908  all expressions
909  all decls
910 
911  TYPE_VOLATILE in
912  all types
913 
914  readonly_flag:
915 
916  TREE_READONLY in
917  all expressions
918  all decls
919 
920  TYPE_READONLY in
921  all types
922 
923  constant_flag:
924 
925  TREE_CONSTANT in
926  all expressions
927  all decls
928  all constants
929 
930  TYPE_SIZES_GIMPLIFIED in
931  all types
932 
933  unsigned_flag:
934 
935  TYPE_UNSIGNED in
936  all types
937 
938  DECL_UNSIGNED in
939  all decls
940 
941  asm_written_flag:
942 
943  TREE_ASM_WRITTEN in
944  VAR_DECL, FUNCTION_DECL, TYPE_DECL
945  RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE
946  BLOCK, STRING_CST
947 
948  SSA_NAME_OCCURS_IN_ABNORMAL_PHI in
949  SSA_NAME
950 
951  used_flag:
952 
953  TREE_USED in
954  all expressions
955  all decls
956  IDENTIFIER_NODE
957 
958  nothrow_flag:
959 
960  TREE_NOTHROW in
961  CALL_EXPR
962  FUNCTION_DECL
963 
964  TYPE_ALIGN_OK in
965  all types
966 
967  TREE_THIS_NOTRAP in
968  INDIRECT_REF, MEM_REF, TARGET_MEM_REF, ARRAY_REF, ARRAY_RANGE_REF
969 
970  SSA_NAME_IN_FREELIST in
971  SSA_NAME
972 
973  deprecated_flag:
974 
975  TREE_DEPRECATED in
976  all decls
977  all types
978 
979  IDENTIFIER_TRANSPARENT_ALIAS in
980  IDENTIFIER_NODE
981 
982  visited:
983 
984  TREE_VISITED in
985  all trees (used liberally by many passes)
986 
987  saturating_flag:
988 
989  TYPE_SATURATING in
990  all types
991 
992  VAR_DECL_IS_VIRTUAL_OPERAND in
993  VAR_DECL
994 
995  nowarning_flag:
996 
997  TREE_NO_WARNING in
998  all expressions
999  all decls
1000 
1001  TYPE_ARTIFICIAL in
1002  all types
1003 
1004  default_def_flag:
1005 
1006  TYPE_VECTOR_OPAQUE in
1007  VECTOR_TYPE
1008 
1009  SSA_NAME_IS_DEFAULT_DEF in
1010  SSA_NAME
1011 
1012  DECL_NONLOCAL_FRAME in
1013  VAR_DECL
1014 
1015  TYPE_FINAL_P in
1016  RECORD_TYPE, UNION_TYPE and QUAL_UNION_TYPE
1017 */
1018 
1019 struct GTY(()) tree_typed {
1020  struct tree_base base;
1021  tree type;
1022 };
1023 
1024 struct GTY(()) tree_common {
1025  struct tree_typed typed;
1026  tree chain;
1027 };
1028 
1029 struct GTY(()) tree_int_cst {
1030  struct tree_typed typed;
1031  double_int int_cst;
1032 };
1033 
1034 
1035 struct GTY(()) tree_real_cst {
1036  struct tree_typed typed;
1037  struct real_value * real_cst_ptr;
1038 };
1039 
1040 struct GTY(()) tree_fixed_cst {
1041  struct tree_typed typed;
1042  struct fixed_value * fixed_cst_ptr;
1043 };
1044 
1045 struct GTY(()) tree_string {
1046  struct tree_typed typed;
1047  int length;
1048  char str[1];
1049 };
1050 
1051 struct GTY(()) tree_complex {
1052  struct tree_typed typed;
1053  tree real;
1054  tree imag;
1055 };
1056 
1057 struct GTY(()) tree_vector {
1058  struct tree_typed typed;
1059  tree GTY ((length ("TYPE_VECTOR_SUBPARTS (TREE_TYPE ((tree)&%h))"))) elts[1];
1060 };
1061 
1062 struct GTY(()) tree_identifier {
1063  struct tree_common common;
1064  struct ht_identifier id;
1065 };
1066 
1067 struct GTY(()) tree_list {
1068  struct tree_common common;
1069  tree purpose;
1070  tree value;
1071 };
1072 
1073 struct GTY(()) tree_vec {
1074  struct tree_common common;
1075  tree GTY ((length ("TREE_VEC_LENGTH ((tree)&%h)"))) a[1];
1076 };
1077 
1078 /* A single element of a CONSTRUCTOR. VALUE holds the actual value of the
1079  element. INDEX can optionally design the position of VALUE: in arrays,
1080  it is the index where VALUE has to be placed; in structures, it is the
1081  FIELD_DECL of the member. */
1082 typedef struct GTY(()) constructor_elt_d {
1083  tree index;
1084  tree value;
1085 } constructor_elt;
1086 
1087 struct GTY(()) tree_constructor {
1088  struct tree_typed typed;
1090 };
1091 
1093 {
1097 };
1098 
1100 {
1105  /* The following kind is an internal only map kind, used for pointer based
1106  array sections. OMP_CLAUSE_SIZE for these is not the pointer size,
1107  which is implicitly POINTER_SIZE / BITS_PER_UNIT, but the bias. */
1109 };
1110 
1112 {
1113  /* Numbers should match omp_proc_bind_t enum in omp.h. */
1119 };
1121 struct GTY(()) tree_exp {
1122  struct tree_typed typed;
1123  location_t locus;
1124  tree GTY ((special ("tree_exp"),
1125  desc ("TREE_CODE ((tree) &%0)")))
1126  operands[1];
1127 };
1128 
1129 /* Immediate use linking structure. This structure is used for maintaining
1130  a doubly linked list of uses of an SSA_NAME. */
1131 typedef struct GTY(()) ssa_use_operand_d {
1132  struct ssa_use_operand_d* GTY((skip(""))) prev;
1133  struct ssa_use_operand_d* GTY((skip(""))) next;
1134  /* Immediate uses for a given SSA name are maintained as a cyclic
1135  list. To recognize the root of this list, the location field
1136  needs to point to the original SSA name. Since statements and
1137  SSA names are of different data types, we need this union. See
1138  the explanation in struct immediate_use_iterator_d. */
1139  union { gimple stmt; tree ssa_name; } GTY((skip(""))) loc;
1140  tree *GTY((skip(""))) use;
1143 struct GTY(()) tree_ssa_name {
1144  struct tree_typed typed;
1146  /* _DECL wrapped by this SSA name. */
1147  tree var;
1149  /* Statement that defines this SSA name. */
1150  gimple def_stmt;
1152  /* Value range information. */
1153  union ssa_name_info_type {
1154  /* Pointer attributes used for alias analysis. */
1155  struct GTY ((tag ("0"))) ptr_info_def *ptr_info;
1156  /* Value range attributes used for zero/sign extension elimination. */
1157  struct GTY ((tag ("1"))) range_info_def *range_info;
1158  } GTY ((desc ("%1.typed.type ?" \
1159  "!POINTER_TYPE_P (TREE_TYPE ((tree)&%1)) : 2"))) info;
1160 
1161  /* Immediate uses list for this SSA_NAME. */
1162  struct ssa_use_operand_d imm_uses;
1163 };
1165 struct GTY(()) phi_arg_d {
1166  /* imm_use MUST be the first element in struct because we do some
1167  pointer arithmetic with it. See phi_arg_index_from_use. */
1168  struct ssa_use_operand_d imm_use;
1170  location_t locus;
1171 };
1172 
1173 struct GTY(()) tree_omp_clause {
1174  struct tree_common common;
1175  location_t locus;
1176  enum omp_clause_code code;
1177  union omp_clause_subcode {
1178  enum omp_clause_default_kind default_kind;
1179  enum omp_clause_schedule_kind schedule_kind;
1180  enum omp_clause_depend_kind depend_kind;
1181  enum omp_clause_map_kind map_kind;
1182  enum omp_clause_proc_bind_kind proc_bind_kind;
1183  enum tree_code reduction_code;
1184  } GTY ((skip)) subcode;
1186  /* The gimplification of OMP_CLAUSE_REDUCTION_{INIT,MERGE} for omp-low's
1187  usage. */
1188  gimple_seq gimple_reduction_init;
1189  gimple_seq gimple_reduction_merge;
1191  tree GTY ((length ("omp_clause_num_ops[OMP_CLAUSE_CODE ((tree)&%h)]")))
1192  ops[1];
1193 };
1194 
1195 struct GTY(()) tree_block {
1196  struct tree_base base;
1198 
1199  unsigned abstract_flag : 1;
1200  unsigned block_num : 31;
1201 
1202  location_t locus;
1204  tree vars;
1205  vec<tree, va_gc> *nonlocalized_vars;
1206 
1207  tree subblocks;
1208  tree supercontext;
1209  tree abstract_origin;
1210  tree fragment_origin;
1211  tree fragment_chain;
1212 };
1214 struct GTY(()) tree_type_common {
1215  struct tree_common common;
1216  tree size;
1217  tree size_unit;
1218  tree attributes;
1219  unsigned int uid;
1221  unsigned int precision : 10;
1222  unsigned no_force_blk_flag : 1;
1223  unsigned needs_constructing_flag : 1;
1224  unsigned transparent_aggr_flag : 1;
1225  unsigned restrict_flag : 1;
1226  unsigned contains_placeholder_bits : 2;
1228  ENUM_BITFIELD(machine_mode) mode : 8;
1229 
1230  unsigned string_flag : 1;
1231  unsigned lang_flag_0 : 1;
1232  unsigned lang_flag_1 : 1;
1233  unsigned lang_flag_2 : 1;
1234  unsigned lang_flag_3 : 1;
1235  unsigned lang_flag_4 : 1;
1236  unsigned lang_flag_5 : 1;
1237  unsigned lang_flag_6 : 1;
1238 
1239  unsigned int align;
1240  alias_set_type alias_set;
1241  tree pointer_to;
1242  tree reference_to;
1243  union tree_type_symtab {
1244  int GTY ((tag ("TYPE_SYMTAB_IS_ADDRESS"))) address;
1245  const char * GTY ((tag ("TYPE_SYMTAB_IS_POINTER"))) pointer;
1246  struct die_struct * GTY ((tag ("TYPE_SYMTAB_IS_DIE"))) die;
1247  } GTY ((desc ("debug_hooks->tree_type_symtab_field"))) symtab;
1248  tree name;
1249  tree next_variant;
1250  tree main_variant;
1251  tree context;
1252  tree canonical;
1253 };
1254 
1255 struct GTY(()) tree_type_with_lang_specific {
1256  struct tree_type_common common;
1257  /* Points to a structure whose details depend on the language in use. */
1258  struct lang_type *lang_specific;
1259 };
1260 
1261 struct GTY(()) tree_type_non_common {
1262  struct tree_type_with_lang_specific with_lang_specific;
1263  tree values;
1264  tree minval;
1265  tree maxval;
1266  tree binfo;
1267 };
1268 
1269 struct GTY (()) tree_binfo {
1270  struct tree_common common;
1271 
1272  tree offset;
1273  tree vtable;
1274  tree virtuals;
1275  tree vptr_field;
1276  vec<tree, va_gc> *base_accesses;
1277  tree inheritance;
1278 
1279  tree vtt_subvtt;
1280  tree vtt_vptr;
1281 
1282  vec<tree, va_gc> base_binfos;
1283 };
1284 
1285 struct GTY(()) tree_decl_minimal {
1286  struct tree_common common;
1287  location_t locus;
1288  unsigned int uid;
1289  tree name;
1290  tree context;
1291 };
1292 
1293 struct GTY(()) tree_decl_common {
1294  struct tree_decl_minimal common;
1295  tree size;
1296 
1297  ENUM_BITFIELD(machine_mode) mode : 8;
1298 
1299  unsigned nonlocal_flag : 1;
1300  unsigned virtual_flag : 1;
1301  unsigned ignored_flag : 1;
1302  unsigned abstract_flag : 1;
1303  unsigned artificial_flag : 1;
1304  unsigned preserve_flag: 1;
1305  unsigned debug_expr_is_from : 1;
1306 
1307  unsigned lang_flag_0 : 1;
1308  unsigned lang_flag_1 : 1;
1309  unsigned lang_flag_2 : 1;
1310  unsigned lang_flag_3 : 1;
1311  unsigned lang_flag_4 : 1;
1312  unsigned lang_flag_5 : 1;
1313  unsigned lang_flag_6 : 1;
1314  unsigned lang_flag_7 : 1;
1315  unsigned lang_flag_8 : 1;
1316 
1317  /* In VAR_DECL and PARM_DECL, this is DECL_REGISTER. */
1318  unsigned decl_flag_0 : 1;
1319  /* In FIELD_DECL, this is DECL_BIT_FIELD
1320  In VAR_DECL and FUNCTION_DECL, this is DECL_EXTERNAL.
1321  In TYPE_DECL, this is TYPE_DECL_SUPPRESS_DEBUG. */
1322  unsigned decl_flag_1 : 1;
1323  /* In FIELD_DECL, this is DECL_NONADDRESSABLE_P
1324  In VAR_DECL, PARM_DECL and RESULT_DECL, this is
1325  DECL_HAS_VALUE_EXPR_P. */
1326  unsigned decl_flag_2 : 1;
1327  /* 1 bit unused. */
1328  unsigned decl_flag_3 : 1;
1329  /* Logically, these two would go in a theoretical base shared by var and
1330  parm decl. */
1331  unsigned gimple_reg_flag : 1;
1332  /* In VAR_DECL, PARM_DECL and RESULT_DECL, this is DECL_BY_REFERENCE. */
1333  unsigned decl_by_reference_flag : 1;
1334  /* In a VAR_DECL and PARM_DECL, this is DECL_READ_P. */
1335  unsigned decl_read_flag : 1;
1336  /* In a VAR_DECL or RESULT_DECL, this is DECL_NONSHAREABLE. */
1337  unsigned decl_nonshareable_flag : 1;
1338 
1339  /* DECL_OFFSET_ALIGN, used only for FIELD_DECLs. */
1340  unsigned int off_align : 8;
1341 
1342  /* 24 bits unused. */
1343 
1344  /* DECL_ALIGN. It should have the same size as TYPE_ALIGN. */
1345  unsigned int align;
1346 
1347  /* UID for points-to sets, stable over copying from inlining. */
1348  unsigned int pt_uid;
1349 
1350  tree size_unit;
1351  tree initial;
1352  tree attributes;
1353  tree abstract_origin;
1354 
1355  /* Points to a structure whose details depend on the language in use. */
1356  struct lang_decl *lang_specific;
1357 };
1358 
1359 struct GTY(()) tree_decl_with_rtl {
1360  struct tree_decl_common common;
1361  rtx rtl;
1362 };
1363 
1364 struct GTY(()) tree_field_decl {
1365  struct tree_decl_common common;
1366 
1367  tree offset;
1368  tree bit_field_type;
1369  tree qualifier;
1370  tree bit_offset;
1371  tree fcontext;
1372 };
1373 
1374 struct GTY(()) tree_label_decl {
1375  struct tree_decl_with_rtl common;
1376  int label_decl_uid;
1377  int eh_landing_pad_nr;
1378 };
1379 
1380 struct GTY(()) tree_result_decl {
1381  struct tree_decl_with_rtl common;
1382 };
1383 
1384 struct GTY(()) tree_const_decl {
1385  struct tree_decl_common common;
1386 };
1387 
1388 struct GTY(()) tree_parm_decl {
1389  struct tree_decl_with_rtl common;
1390  rtx incoming_rtl;
1391 };
1392 
1393 struct GTY(()) tree_decl_with_vis {
1394  struct tree_decl_with_rtl common;
1395  tree assembler_name;
1396  tree section_name;
1397  tree comdat_group;
1398 
1399  /* Belong to VAR_DECL exclusively. */
1400  unsigned defer_output : 1;
1401  unsigned hard_register : 1;
1402  unsigned common_flag : 1;
1403  unsigned in_text_section : 1;
1404  unsigned in_constant_pool : 1;
1405  unsigned dllimport_flag : 1;
1406  /* Don't belong to VAR_DECL exclusively. */
1407  unsigned weak_flag : 1;
1408  /* When SECTION_NAME is implied by -ffunction-section. */
1409  unsigned implicit_section_name_p : 1;
1410 
1411  unsigned seen_in_bind_expr : 1;
1412  unsigned comdat_flag : 1;
1413  ENUM_BITFIELD(symbol_visibility) visibility : 2;
1414  unsigned visibility_specified : 1;
1415  /* Belongs to VAR_DECL exclusively. */
1416  ENUM_BITFIELD(tls_model) tls_model : 3;
1417 
1418  /* Belong to FUNCTION_DECL exclusively. */
1419  unsigned init_priority_p : 1;
1420  /* Used by C++ only. Might become a generic decl flag. */
1421  unsigned shadowed_for_var_p : 1;
1422  /* Belong to FUNCTION_DECL exclusively. */
1423  unsigned cxx_constructor : 1;
1424  /* Belong to FUNCTION_DECL exclusively. */
1425  unsigned cxx_destructor : 1;
1426  /* Belong to FUNCTION_DECL exclusively. */
1427  unsigned final : 1;
1428  /* 11 unused bits. */
1429 };
1430 
1431 struct GTY(()) tree_var_decl {
1432  struct tree_decl_with_vis common;
1433 };
1434 
1435 struct GTY(()) tree_decl_non_common {
1436  struct tree_decl_with_vis common;
1437  /* C++ uses this in namespaces. */
1438  tree saved_tree;
1439  /* C++ uses this in templates. */
1440  tree arguments;
1441  /* Almost all FE's use this. */
1442  tree result;
1443  /* C++ uses this in namespaces and function_decls. */
1444  tree vindex;
1445 };
1446 
1447 /* FUNCTION_DECL inherits from DECL_NON_COMMON because of the use of the
1448  arguments/result/saved_tree fields by front ends. It was either inherit
1449  FUNCTION_DECL from non_common, or inherit non_common from FUNCTION_DECL,
1450  which seemed a bit strange. */
1451 
1452 struct GTY(()) tree_function_decl {
1453  struct tree_decl_non_common common;
1454 
1455  struct function *f;
1456 
1457  /* The personality function. Used for stack unwinding. */
1458  tree personality;
1459 
1460  /* Function specific options that are used by this function. */
1461  tree function_specific_target; /* target options */
1462  tree function_specific_optimization; /* optimization options */
1463 
1464  /* In a FUNCTION_DECL for which DECL_BUILT_IN holds, this is
1465  DECL_FUNCTION_CODE. Otherwise unused.
1466  ??? The bitfield needs to be able to hold all target function
1467  codes as well. */
1468  ENUM_BITFIELD(built_in_function) function_code : 11;
1469  ENUM_BITFIELD(built_in_class) built_in_class : 2;
1470 
1471  unsigned static_ctor_flag : 1;
1472  unsigned static_dtor_flag : 1;
1473  unsigned uninlinable : 1;
1474 
1475  unsigned possibly_inlined : 1;
1476  unsigned novops_flag : 1;
1477  unsigned returns_twice_flag : 1;
1478  unsigned malloc_flag : 1;
1479  unsigned operator_new_flag : 1;
1480  unsigned declared_inline_flag : 1;
1481  unsigned regdecl_flag : 1;
1482  unsigned no_inline_warning_flag : 1;
1483 
1484  unsigned no_instrument_function_entry_exit : 1;
1485  unsigned no_limit_stack : 1;
1486  unsigned disregard_inline_limits : 1;
1487  unsigned pure_flag : 1;
1488  unsigned looping_const_or_pure_flag : 1;
1489  unsigned has_debug_args_flag : 1;
1490  unsigned tm_clone_flag : 1;
1491  unsigned versioned_function : 1;
1492  /* No bits left. */
1493 };
1494 
1495 struct GTY(()) tree_translation_unit_decl {
1496  struct tree_decl_common common;
1497  /* Source language of this translation unit. Used for DWARF output. */
1498  const char * GTY((skip(""))) language;
1499  /* TODO: Non-optimization used to build this translation unit. */
1500  /* TODO: Root of a partial DWARF tree for global types and decls. */
1501 };
1502 
1503 struct GTY(()) tree_type_decl {
1504  struct tree_decl_non_common common;
1505 
1506 };
1507 
1508 struct GTY ((chain_next ("%h.next"), chain_prev ("%h.prev"))) tree_statement_list_node
1509  {
1510  struct tree_statement_list_node *prev;
1511  struct tree_statement_list_node *next;
1512  tree stmt;
1513 };
1514 
1515 struct GTY(()) tree_statement_list
1516  {
1517  struct tree_typed typed;
1518  struct tree_statement_list_node *head;
1519  struct tree_statement_list_node *tail;
1520 };
1521 
1522 
1523 /* Optimization options used by a function. */
1524 
1525 struct GTY(()) tree_optimization_option {
1526  struct tree_common common;
1527 
1528  /* The optimization options used by the user. */
1529  struct cl_optimization opts;
1530 
1531  /* Target optabs for this set of optimization options. This is of
1532  type `struct target_optabs *'. */
1533  unsigned char *GTY ((atomic)) optabs;
1534 
1535  /* The value of this_target_optabs against which the optabs above were
1536  generated. */
1537  struct target_optabs *GTY ((skip)) base_optabs;
1538 };
1539 
1540 /* Target options used by a function. */
1541 
1542 struct GTY(()) tree_target_option {
1543  struct tree_common common;
1544 
1545  /* The optimization options used by the user. */
1546  struct cl_target_option opts;
1547 };
1548 
1549 /* Define the overall contents of a tree node.
1550  It may be any of the structures declared above
1551  for various types of node. */
1552 union GTY ((ptr_alias (union lang_tree_node),
1553  desc ("tree_node_structure (&%h)"), variable_size)) tree_node {
1554  struct tree_base GTY ((tag ("TS_BASE"))) base;
1555  struct tree_typed GTY ((tag ("TS_TYPED"))) typed;
1556  struct tree_common GTY ((tag ("TS_COMMON"))) common;
1557  struct tree_int_cst GTY ((tag ("TS_INT_CST"))) int_cst;
1558  struct tree_real_cst GTY ((tag ("TS_REAL_CST"))) real_cst;
1559  struct tree_fixed_cst GTY ((tag ("TS_FIXED_CST"))) fixed_cst;
1560  struct tree_vector GTY ((tag ("TS_VECTOR"))) vector;
1561  struct tree_string GTY ((tag ("TS_STRING"))) string;
1562  struct tree_complex GTY ((tag ("TS_COMPLEX"))) complex;
1563  struct tree_identifier GTY ((tag ("TS_IDENTIFIER"))) identifier;
1564  struct tree_decl_minimal GTY((tag ("TS_DECL_MINIMAL"))) decl_minimal;
1565  struct tree_decl_common GTY ((tag ("TS_DECL_COMMON"))) decl_common;
1566  struct tree_decl_with_rtl GTY ((tag ("TS_DECL_WRTL"))) decl_with_rtl;
1567  struct tree_decl_non_common GTY ((tag ("TS_DECL_NON_COMMON")))
1568  decl_non_common;
1569  struct tree_parm_decl GTY ((tag ("TS_PARM_DECL"))) parm_decl;
1570  struct tree_decl_with_vis GTY ((tag ("TS_DECL_WITH_VIS"))) decl_with_vis;
1571  struct tree_var_decl GTY ((tag ("TS_VAR_DECL"))) var_decl;
1572  struct tree_field_decl GTY ((tag ("TS_FIELD_DECL"))) field_decl;
1573  struct tree_label_decl GTY ((tag ("TS_LABEL_DECL"))) label_decl;
1574  struct tree_result_decl GTY ((tag ("TS_RESULT_DECL"))) result_decl;
1575  struct tree_const_decl GTY ((tag ("TS_CONST_DECL"))) const_decl;
1576  struct tree_type_decl GTY ((tag ("TS_TYPE_DECL"))) type_decl;
1577  struct tree_function_decl GTY ((tag ("TS_FUNCTION_DECL"))) function_decl;
1578  struct tree_translation_unit_decl GTY ((tag ("TS_TRANSLATION_UNIT_DECL")))
1579  translation_unit_decl;
1580  struct tree_type_common GTY ((tag ("TS_TYPE_COMMON"))) type_common;
1581  struct tree_type_with_lang_specific GTY ((tag ("TS_TYPE_WITH_LANG_SPECIFIC")))
1582  type_with_lang_specific;
1583  struct tree_type_non_common GTY ((tag ("TS_TYPE_NON_COMMON")))
1584  type_non_common;
1585  struct tree_list GTY ((tag ("TS_LIST"))) list;
1586  struct tree_vec GTY ((tag ("TS_VEC"))) vec;
1587  struct tree_exp GTY ((tag ("TS_EXP"))) exp;
1588  struct tree_ssa_name GTY ((tag ("TS_SSA_NAME"))) ssa_name;
1589  struct tree_block GTY ((tag ("TS_BLOCK"))) block;
1590  struct tree_binfo GTY ((tag ("TS_BINFO"))) binfo;
1591  struct tree_statement_list GTY ((tag ("TS_STATEMENT_LIST"))) stmt_list;
1592  struct tree_constructor GTY ((tag ("TS_CONSTRUCTOR"))) constructor;
1593  struct tree_omp_clause GTY ((tag ("TS_OMP_CLAUSE"))) omp_clause;
1594  struct tree_optimization_option GTY ((tag ("TS_OPTIMIZATION"))) optimization;
1595  struct tree_target_option GTY ((tag ("TS_TARGET_OPTION"))) target_option;
1596 };
1597 
1598 /* Structure describing an attribute and a function to handle it. */
1599 struct attribute_spec {
1600  /* The name of the attribute (without any leading or trailing __),
1601  or NULL to mark the end of a table of attributes. */
1602  const char *name;
1603  /* The minimum length of the list of arguments of the attribute. */
1604  int min_length;
1605  /* The maximum length of the list of arguments of the attribute
1606  (-1 for no maximum). */
1607  int max_length;
1608  /* Whether this attribute requires a DECL. If it does, it will be passed
1609  from types of DECLs, function return types and array element types to
1610  the DECLs, function types and array types respectively; but when
1611  applied to a type in any other circumstances, it will be ignored with
1612  a warning. (If greater control is desired for a given attribute,
1613  this should be false, and the flags argument to the handler may be
1614  used to gain greater control in that case.) */
1615  bool decl_required;
1616  /* Whether this attribute requires a type. If it does, it will be passed
1617  from a DECL to the type of that DECL. */
1618  bool type_required;
1619  /* Whether this attribute requires a function (or method) type. If it does,
1620  it will be passed from a function pointer type to the target type,
1621  and from a function return type (which is not itself a function
1622  pointer type) to the function type. */
1623  bool function_type_required;
1624  /* Function to handle this attribute. NODE points to the node to which
1625  the attribute is to be applied. If a DECL, it should be modified in
1626  place; if a TYPE, a copy should be created. NAME is the name of the
1627  attribute (possibly with leading or trailing __). ARGS is the TREE_LIST
1628  of the arguments (which may be NULL). FLAGS gives further information
1629  about the context of the attribute. Afterwards, the attributes will
1630  be added to the DECL_ATTRIBUTES or TYPE_ATTRIBUTES, as appropriate,
1631  unless *NO_ADD_ATTRS is set to true (which should be done on error,
1632  as well as in any other cases when the attributes should not be added
1633  to the DECL or TYPE). Depending on FLAGS, any attributes to be
1634  applied to another type or DECL later may be returned;
1635  otherwise the return value should be NULL_TREE. This pointer may be
1636  NULL if no special handling is required beyond the checks implied
1637  by the rest of this structure. */
1638  tree (*handler) (tree *node, tree name, tree args,
1639  int flags, bool *no_add_attrs);
1640  /* Specifies if attribute affects type's identity. */
1641  bool affects_type_identity;
1642 };
1643 
1644 /* These functions allow a front-end to perform a manual layout of a
1645  RECORD_TYPE. (For instance, if the placement of subsequent fields
1646  depends on the placement of fields so far.) Begin by calling
1647  start_record_layout. Then, call place_field for each of the
1648  fields. Then, call finish_record_layout. See layout_type for the
1649  default way in which these functions are used. */
1650 typedef struct record_layout_info_s {
1651  /* The RECORD_TYPE that we are laying out. */
1652  tree t;
1653  /* The offset into the record so far, in bytes, not including bits in
1654  BITPOS. */
1655  tree offset;
1656  /* The last known alignment of SIZE. */
1657  unsigned int offset_align;
1658  /* The bit position within the last OFFSET_ALIGN bits, in bits. */
1659  tree bitpos;
1660  /* The alignment of the record so far, in bits. */
1661  unsigned int record_align;
1662  /* The alignment of the record so far, ignoring #pragma pack and
1663  __attribute__ ((packed)), in bits. */
1664  unsigned int unpacked_align;
1665  /* The previous field laid out. */
1666  tree prev_field;
1667  /* The static variables (i.e., class variables, as opposed to
1668  instance variables) encountered in T. */
1669  vec<tree, va_gc> *pending_statics;
1670  /* Bits remaining in the current alignment group */
1671  int remaining_in_alignment;
1672  /* True if we've seen a packed field that didn't have normal
1673  alignment anyway. */
1674  int packed_maybe_necessary;
1675 } *record_layout_info;
1676 
1677 /* Iterator for going through the function arguments. */
1678 struct function_args_iterator {
1679  tree next; /* TREE_LIST pointing to the next argument */
1680 };
1681 
1682 /* Structures to map from a tree to another tree. */
1683 struct GTY(()) tree_map_base {
1684  tree from;
1685 };
1686 
1687 /* Map from a tree to another tree. */
1688 
1689 struct GTY(()) tree_map {
1690  struct tree_map_base base;
1691  unsigned int hash;
1692  tree to;
1693 };
1694 
1695 /* Map from a decl tree to another tree. */
1696 struct GTY(()) tree_decl_map {
1697  struct tree_map_base base;
1698  tree to;
1699 };
1700 
1701 /* Map from a tree to an int. */
1702 struct GTY(()) tree_int_map {
1703  struct tree_map_base base;
1704  unsigned int to;
1705 };
1706 
1707 /* Map from a tree to initialization/finalization priorities. */
1708 struct GTY(()) tree_priority_map {
1709  struct tree_map_base base;
1710  priority_type init;
1711  priority_type fini;
1712 };
1713 
1714 /* Map from a decl tree to a tree vector. */
1715 struct GTY(()) tree_vec_map {
1716  struct tree_map_base base;
1717  vec<tree, va_gc> *to;
1718 };
1719 
1720 /* Abstract iterators for CALL_EXPRs. These static inline definitions
1721  have to go towards the end of tree.h so that union tree_node is fully
1722  defined by this point. */
1723 
1724 /* Structure containing iterator state. */
1725 struct call_expr_arg_iterator {
1726  tree t; /* the call_expr */
1727  int n; /* argument count */
1728  int i; /* next argument index */
1729 };
1730 
1731 struct const_call_expr_arg_iterator {
1732  const_tree t; /* the call_expr */
1733  int n; /* argument count */
1734  int i; /* next argument index */
1735 };
1736 
1737 /* The builtin_info structure holds the FUNCTION_DECL of the standard builtin
1738  function, and a flag that says if the function is available implicitly, or
1739  whether the user has to code explicit calls to __builtin_<xxx>. */
1740 struct GTY(()) builtin_info_type {
1741  tree decl[(int)END_BUILTINS];
1742  bool implicit_p[(int)END_BUILTINS];
1743 };
1744 
1745 
1746 /*---------------------------------------------------------------------------
1747  Global variables
1748 ---------------------------------------------------------------------------*/
1749 /* Matrix describing the structures contained in a given tree code. */
1750 extern unsigned char tree_contains_struct[MAX_TREE_CODES][64];
1751 
1752 /* Class of tree given its code. */
1753 extern const enum tree_code_class tree_code_type[];
1754 
1755 /* Each tree code class has an associated string representation.
1756  These must correspond to the tree_code_class entries. */
1757 extern const char *const tree_code_class_strings[];
1758 
1759 /* Number of argument-words in each kind of tree-node. */
1760 extern const unsigned char tree_code_length[];
1761 
1762 /* Vector of all alias pairs for global symbols. */
1763 extern GTY(()) vec<alias_pair, va_gc> *alias_pairs;
1764 
1765 /* Names of all the built_in classes. */
1766 extern const char *const built_in_class_names[BUILT_IN_LAST];
1767 
1768 /* Names of all the built_in functions. */
1769 extern const char * built_in_names[(int) END_BUILTINS];
1770 
1771 /* Number of operands and names for each OMP_CLAUSE node. */
1772 extern unsigned const char omp_clause_num_ops[];
1773 extern const char * const omp_clause_code_name[];
1774 
1775 /* A vector of all translation-units. */
1776 extern GTY (()) vec<tree, va_gc> *all_translation_units;
1777 
1778 /* Vector of standard trees used by the C compiler. */
1779 extern GTY(()) tree global_trees[TI_MAX];
1780 
1781 /* The standard C integer types. Use integer_type_kind to index into
1782  this array. */
1783 extern GTY(()) tree integer_types[itk_none];
1784 
1785 /* Types used to represent sizes. */
1786 extern GTY(()) tree sizetype_tab[(int) stk_type_kind_last];
1787 
1788 /* Arrays for keeping track of tree node statistics. */
1789 extern int tree_node_counts[];
1790 extern int tree_node_sizes[];
1791 
1792 /* True if we are in gimple form and the actions of the folders need to
1793  be restricted. False if we are not in gimple form and folding is not
1794  restricted to creating gimple expressions. */
1795 extern bool in_gimple_form;
1796 
1797 /* Functional interface to the builtin functions. */
1798 extern GTY(()) builtin_info_type builtin_info;
1799 
1800 /* If nonzero, an upper limit on alignment of structure fields, in bits, */
1801 extern unsigned int maximum_field_alignment;
1802 
1803 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
1804  Zero means allow extended lvalues. */
1805 extern int pedantic_lvalues;
1806 
1807 /* Points to the FUNCTION_DECL of the function whose body we are reading. */
1808 extern GTY(()) tree current_function_decl;
1809 
1810 /* Nonzero means a FUNC_BEGIN label was emitted. */
1811 extern GTY(()) const char * current_function_func_begin_label;
1812 
1813 #endif // GCC_TREE_CORE_H