This file is indexed.

/usr/lib/gcc-cross/powerpc-linux-gnu/6/plugin/include/tree-core.h is in gcc-6-plugin-dev-powerpc-linux-gnu 6.4.0-17ubuntu1cross1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
/* Core data structures for the 'tree' type.
   Copyright (C) 1989-2016 Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */

#ifndef GCC_TREE_CORE_H
#define GCC_TREE_CORE_H

#include "symtab.h"

/* This file contains all the data structures that define the 'tree' type.
   There are no accessor macros nor functions in this file. Only the
   basic data structures, extern declarations and type definitions.  */

/*---------------------------------------------------------------------------
   Forward type declarations.  Mostly to avoid including unnecessary headers
---------------------------------------------------------------------------*/
struct function;
struct real_value;
struct fixed_value;
struct ptr_info_def;
struct range_info_def;
struct die_struct;


/*---------------------------------------------------------------------------
                              #defined constants
---------------------------------------------------------------------------*/
/* Nonzero if this is a call to a function whose return value depends
   solely on its arguments, has no side effects, and does not read
   global memory.  This corresponds to TREE_READONLY for function
   decls.  */
#define ECF_CONST		  (1 << 0)

/* Nonzero if this is a call to "pure" function (like const function,
   but may read memory.  This corresponds to DECL_PURE_P for function
   decls.  */
#define ECF_PURE		  (1 << 1)

/* Nonzero if this is ECF_CONST or ECF_PURE but cannot be proven to no
   infinite loop.  This corresponds to DECL_LOOPING_CONST_OR_PURE_P
   for function decls.*/
#define ECF_LOOPING_CONST_OR_PURE (1 << 2)

/* Nonzero if this call will never return.  */
#define ECF_NORETURN		  (1 << 3)

/* Nonzero if this is a call to malloc or a related function.  */
#define ECF_MALLOC		  (1 << 4)

/* Nonzero if it is plausible that this is a call to alloca.  */
#define ECF_MAY_BE_ALLOCA	  (1 << 5)

/* Nonzero if this is a call to a function that won't throw an exception.  */
#define ECF_NOTHROW		  (1 << 6)

/* Nonzero if this is a call to setjmp or a related function.  */
#define ECF_RETURNS_TWICE	  (1 << 7)

/* Nonzero if this call replaces the current stack frame.  */
#define ECF_SIBCALL		  (1 << 8)

/* Function does not read or write memory (but may have side effects, so
   it does not necessarily fit ECF_CONST).  */
#define ECF_NOVOPS		  (1 << 9)

/* The function does not lead to calls within current function unit.  */
#define ECF_LEAF		  (1 << 10)

/* Nonzero if this call does not affect transactions.  */
#define ECF_TM_PURE		  (1 << 11)

/* Nonzero if this call is into the transaction runtime library.  */
#define ECF_TM_BUILTIN		  (1 << 12)

/* Call argument flags.  */
/* Nonzero if the argument is not dereferenced recursively, thus only
   directly reachable memory is read or written.  */
#define EAF_DIRECT		(1 << 0)

/* Nonzero if memory reached by the argument is not clobbered.  */
#define EAF_NOCLOBBER		(1 << 1)

/* Nonzero if the argument does not escape.  */
#define EAF_NOESCAPE		(1 << 2)

/* Nonzero if the argument is not used by the function.  */
#define EAF_UNUSED		(1 << 3)

/* Call return flags.  */
/* Mask for the argument number that is returned.  Lower two bits of
   the return flags, encodes argument slots zero to three.  */
#define ERF_RETURN_ARG_MASK	(3)

/* Nonzero if the return value is equal to the argument number
   flags & ERF_RETURN_ARG_MASK.  */
#define ERF_RETURNS_ARG		(1 << 2)

/* Nonzero if the return value does not alias with anything.  Functions
   with the malloc attribute have this set on their return value.  */
#define ERF_NOALIAS		(1 << 3)


/*---------------------------------------------------------------------------
                                  Enumerations
---------------------------------------------------------------------------*/
/* Codes of tree nodes.  */
#define DEFTREECODE(SYM, STRING, TYPE, NARGS)   SYM,
#define END_OF_BASE_TREE_CODES LAST_AND_UNUSED_TREE_CODE,

enum tree_code {
#include "all-tree.def"
MAX_TREE_CODES
};

#undef DEFTREECODE
#undef END_OF_BASE_TREE_CODES

/* Number of language-independent tree codes.  */
#define NUM_TREE_CODES \
  ((int) LAST_AND_UNUSED_TREE_CODE)

#define CODE_CONTAINS_STRUCT(CODE, STRUCT) \
  (tree_contains_struct[(CODE)][(STRUCT)])


/* Classify which part of the compiler has defined a given builtin function.
   Note that we assume below that this is no more than two bits.  */
enum built_in_class {
  NOT_BUILT_IN = 0,
  BUILT_IN_FRONTEND,
  BUILT_IN_MD,
  BUILT_IN_NORMAL
};

/* Last marker used for LTO stremaing of built_in_class.  We can not add it
   to the enum since we need the enumb to fit in 2 bits.  */
#define BUILT_IN_LAST (BUILT_IN_NORMAL + 1)

/* Codes that identify the various built in functions
   so that expand_call can identify them quickly.  */
#define DEF_BUILTIN(ENUM, N, C, T, LT, B, F, NA, AT, IM, COND) ENUM,
enum built_in_function {
#include "builtins.def"

  BEGIN_CHKP_BUILTINS,

#define DEF_BUILTIN(ENUM, N, C, T, LT, B, F, NA, AT, IM, COND)
#define DEF_BUILTIN_CHKP(ENUM, N, C, T, LT, B, F, NA, AT, IM, COND) \
  ENUM##_CHKP = ENUM + BEGIN_CHKP_BUILTINS + 1,
#include "builtins.def"

  END_CHKP_BUILTINS = BEGIN_CHKP_BUILTINS * 2 + 1,

  /* Complex division routines in libgcc.  These are done via builtins
     because emit_library_call_value can't handle complex values.  */
  BUILT_IN_COMPLEX_MUL_MIN,
  BUILT_IN_COMPLEX_MUL_MAX
    = BUILT_IN_COMPLEX_MUL_MIN
      + MAX_MODE_COMPLEX_FLOAT
      - MIN_MODE_COMPLEX_FLOAT,

  BUILT_IN_COMPLEX_DIV_MIN,
  BUILT_IN_COMPLEX_DIV_MAX
    = BUILT_IN_COMPLEX_DIV_MIN
      + MAX_MODE_COMPLEX_FLOAT
      - MIN_MODE_COMPLEX_FLOAT,

  /* Upper bound on non-language-specific builtins.  */
  END_BUILTINS
};

/* Internal functions.  */
enum internal_fn {
#define DEF_INTERNAL_FN(CODE, FLAGS, FNSPEC) IFN_##CODE,
#include "internal-fn.def"
  IFN_LAST
};

/* An enum that combines target-independent built-in functions with
   internal functions, so that they can be treated in a similar way.
   The numbers for built-in functions are the same as for the
   built_in_function enum.  The numbers for internal functions
   start at END_BUITLINS.  */
enum combined_fn {
#define DEF_BUILTIN(ENUM, N, C, T, LT, B, F, NA, AT, IM, COND) \
  CFN_##ENUM = int (ENUM),
#include "builtins.def"

#define DEF_BUILTIN(ENUM, N, C, T, LT, B, F, NA, AT, IM, COND)
#define DEF_BUILTIN_CHKP(ENUM, N, C, T, LT, B, F, NA, AT, IM, COND) \
  CFN_##ENUM##_CHKP = int (ENUM##_CHKP),
#include "builtins.def"

#define DEF_INTERNAL_FN(CODE, FLAGS, FNSPEC) \
  CFN_##CODE = int (END_BUILTINS) + int (IFN_##CODE),
#include "internal-fn.def"

  CFN_LAST
};

/* Tree code classes.  Each tree_code has an associated code class
   represented by a TREE_CODE_CLASS.  */
enum tree_code_class {
  tcc_exceptional, /* An exceptional code (fits no category).  */
  tcc_constant,    /* A constant.  */
  /* Order of tcc_type and tcc_declaration is important.  */
  tcc_type,        /* A type object code.  */
  tcc_declaration, /* A declaration (also serving as variable refs).  */
  tcc_reference,   /* A reference to storage.  */
  tcc_comparison,  /* A comparison expression.  */
  tcc_unary,       /* A unary arithmetic expression.  */
  tcc_binary,      /* A binary arithmetic expression.  */
  tcc_statement,   /* A statement expression, which have side effects
		      but usually no interesting value.  */
  tcc_vl_exp,      /* A function call or other expression with a
		      variable-length operand vector.  */
  tcc_expression   /* Any other expression.  */
};

/* OMP_CLAUSE codes.  Do not reorder, as this is used to index into
   the tables omp_clause_num_ops and omp_clause_code_name.  */
enum omp_clause_code {
  /* Clause zero is special-cased inside the parser
     (c_parser_omp_variable_list).  */
  OMP_CLAUSE_ERROR = 0,

  /* OpenACC/OpenMP clause: private (variable_list).  */
  OMP_CLAUSE_PRIVATE,

  /* OpenMP clause: shared (variable_list).  */
  OMP_CLAUSE_SHARED,

  /* OpenACC/OpenMP clause: firstprivate (variable_list).  */
  OMP_CLAUSE_FIRSTPRIVATE,

  /* OpenMP clause: lastprivate (variable_list).  */
  OMP_CLAUSE_LASTPRIVATE,

  /* OpenACC/OpenMP clause: reduction (operator:variable_list).
     OMP_CLAUSE_REDUCTION_CODE: The tree_code of the operator.
     Operand 1: OMP_CLAUSE_REDUCTION_INIT: Stmt-list to initialize the var.
     Operand 2: OMP_CLAUSE_REDUCTION_MERGE: Stmt-list to merge private var
                into the shared one.
     Operand 3: OMP_CLAUSE_REDUCTION_PLACEHOLDER: A dummy VAR_DECL
                placeholder used in OMP_CLAUSE_REDUCTION_{INIT,MERGE}.
     Operand 4: OMP_CLAUSE_REDUCTION_DECL_PLACEHOLDER: Another dummy
		VAR_DECL placeholder, used like the above for C/C++ array
		reductions.  */
  OMP_CLAUSE_REDUCTION,

  /* OpenMP clause: copyin (variable_list).  */
  OMP_CLAUSE_COPYIN,

  /* OpenMP clause: copyprivate (variable_list).  */
  OMP_CLAUSE_COPYPRIVATE,

  /* OpenMP clause: linear (variable-list[:linear-step]).  */
  OMP_CLAUSE_LINEAR,

  /* OpenMP clause: aligned (variable-list[:alignment]).  */
  OMP_CLAUSE_ALIGNED,

  /* OpenMP clause: depend ({in,out,inout}:variable-list).  */
  OMP_CLAUSE_DEPEND,

  /* OpenMP clause: uniform (argument-list).  */
  OMP_CLAUSE_UNIFORM,

  /* OpenMP clause: to (extended-list).
     Only when it appears in declare target.  */
  OMP_CLAUSE_TO_DECLARE,

  /* OpenMP clause: link (variable-list).  */
  OMP_CLAUSE_LINK,

  /* OpenMP clause: from (variable-list).  */
  OMP_CLAUSE_FROM,

  /* OpenMP clause: to (variable-list).  */
  OMP_CLAUSE_TO,

  /* OpenACC clauses: {copy, copyin, copyout, create, delete, deviceptr,
     device, host (self), present, present_or_copy (pcopy), present_or_copyin
     (pcopyin), present_or_copyout (pcopyout), present_or_create (pcreate)}
     (variable-list).

     OpenMP clause: map ({alloc:,to:,from:,tofrom:,}variable-list).  */
  OMP_CLAUSE_MAP,

  /* OpenACC clause: use_device (variable_list).
     OpenMP clause: use_device_ptr (variable-list).  */
  OMP_CLAUSE_USE_DEVICE_PTR,

  /* OpenMP clause: is_device_ptr (variable-list).  */
  OMP_CLAUSE_IS_DEVICE_PTR,

  /* Internal structure to hold OpenACC cache directive's variable-list.
     #pragma acc cache (variable-list).  */
  OMP_CLAUSE__CACHE_,

  /* OpenACC clause: device_resident (variable_list).  */
  OMP_CLAUSE_DEVICE_RESIDENT,

  /* OpenACC clause: gang [(gang-argument-list)].
     Where
      gang-argument-list: [gang-argument-list, ] gang-argument
      gang-argument: [num:] integer-expression
                   | static: size-expression
      size-expression: * | integer-expression.  */
  OMP_CLAUSE_GANG,

  /* OpenACC clause: async [(integer-expression)].  */
  OMP_CLAUSE_ASYNC,

  /* OpenACC clause: wait [(integer-expression-list)].  */
  OMP_CLAUSE_WAIT,

  /* OpenACC clause: auto.  */
  OMP_CLAUSE_AUTO,

  /* OpenACC clause: seq.  */
  OMP_CLAUSE_SEQ,

  /* Internal clause: temporary for combined loops expansion.  */
  OMP_CLAUSE__LOOPTEMP_,

  /* OpenACC/OpenMP clause: if (scalar-expression).  */
  OMP_CLAUSE_IF,

  /* OpenMP clause: num_threads (integer-expression).  */
  OMP_CLAUSE_NUM_THREADS,

  /* OpenMP clause: schedule.  */
  OMP_CLAUSE_SCHEDULE,

  /* OpenMP clause: nowait.  */
  OMP_CLAUSE_NOWAIT,

  /* OpenMP clause: ordered [(constant-integer-expression)].  */
  OMP_CLAUSE_ORDERED,

  /* OpenMP clause: default.  */
  OMP_CLAUSE_DEFAULT,

  /* OpenACC/OpenMP clause: collapse (constant-integer-expression).  */
  OMP_CLAUSE_COLLAPSE,

  /* OpenMP clause: untied.  */
  OMP_CLAUSE_UNTIED,

  /* OpenMP clause: final (scalar-expression).  */
  OMP_CLAUSE_FINAL,

  /* OpenMP clause: mergeable.  */
  OMP_CLAUSE_MERGEABLE,

  /* OpenMP clause: device (integer-expression).  */
  OMP_CLAUSE_DEVICE,

  /* OpenMP clause: dist_schedule (static[:chunk-size]).  */
  OMP_CLAUSE_DIST_SCHEDULE,

  /* OpenMP clause: inbranch.  */
  OMP_CLAUSE_INBRANCH,

  /* OpenMP clause: notinbranch.  */
  OMP_CLAUSE_NOTINBRANCH,

  /* OpenMP clause: num_teams(integer-expression).  */
  OMP_CLAUSE_NUM_TEAMS,

  /* OpenMP clause: thread_limit(integer-expression).  */
  OMP_CLAUSE_THREAD_LIMIT,

  /* OpenMP clause: proc_bind ({master,close,spread}).  */
  OMP_CLAUSE_PROC_BIND,

  /* OpenMP clause: safelen (constant-integer-expression).  */
  OMP_CLAUSE_SAFELEN,

  /* OpenMP clause: simdlen (constant-integer-expression).  */
  OMP_CLAUSE_SIMDLEN,

  /* OpenMP clause: for.  */
  OMP_CLAUSE_FOR,

  /* OpenMP clause: parallel.  */
  OMP_CLAUSE_PARALLEL,

  /* OpenMP clause: sections.  */
  OMP_CLAUSE_SECTIONS,

  /* OpenMP clause: taskgroup.  */
  OMP_CLAUSE_TASKGROUP,

  /* OpenMP clause: priority (integer-expression).  */
  OMP_CLAUSE_PRIORITY,

  /* OpenMP clause: grainsize (integer-expression).  */
  OMP_CLAUSE_GRAINSIZE,

  /* OpenMP clause: num_tasks (integer-expression).  */
  OMP_CLAUSE_NUM_TASKS,

  /* OpenMP clause: nogroup.  */
  OMP_CLAUSE_NOGROUP,

  /* OpenMP clause: threads.  */
  OMP_CLAUSE_THREADS,

  /* OpenMP clause: simd.  */
  OMP_CLAUSE_SIMD,

  /* OpenMP clause: hint (integer-expression).  */
  OMP_CLAUSE_HINT,

  /* OpenMP clause: defaultmap (tofrom: scalar).  */
  OMP_CLAUSE_DEFAULTMAP,

  /* Internally used only clause, holding SIMD uid.  */
  OMP_CLAUSE__SIMDUID_,

  /* Internally used only clause, holding _Cilk_for # of iterations
     on OMP_PARALLEL.  */
  OMP_CLAUSE__CILK_FOR_COUNT_,

  /* OpenACC clause: independent.  */
  OMP_CLAUSE_INDEPENDENT,

  /* OpenACC clause: worker [( [num:] integer-expression)].  */
  OMP_CLAUSE_WORKER,

  /* OpenACC clause: vector [( [length:] integer-expression)].  */
  OMP_CLAUSE_VECTOR,

  /* OpenACC clause: num_gangs (integer-expression).  */
  OMP_CLAUSE_NUM_GANGS,

  /* OpenACC clause: num_workers (integer-expression).  */
  OMP_CLAUSE_NUM_WORKERS,

  /* OpenACC clause: vector_length (integer-expression).  */
  OMP_CLAUSE_VECTOR_LENGTH,

  /* OpenACC clause: tile ( size-expr-list ).  */
  OMP_CLAUSE_TILE,

  /* OpenMP internal-only clause to specify grid dimensions of a gridified
     kernel.  */
  OMP_CLAUSE__GRIDDIM_
};

#undef DEFTREESTRUCT
#define DEFTREESTRUCT(ENUM, NAME) ENUM,
enum tree_node_structure_enum {
#include "treestruct.def"
  LAST_TS_ENUM
};
#undef DEFTREESTRUCT

enum omp_clause_schedule_kind {
  OMP_CLAUSE_SCHEDULE_STATIC,
  OMP_CLAUSE_SCHEDULE_DYNAMIC,
  OMP_CLAUSE_SCHEDULE_GUIDED,
  OMP_CLAUSE_SCHEDULE_AUTO,
  OMP_CLAUSE_SCHEDULE_RUNTIME,
  OMP_CLAUSE_SCHEDULE_CILKFOR,
  OMP_CLAUSE_SCHEDULE_MASK = (1 << 3) - 1,
  OMP_CLAUSE_SCHEDULE_MONOTONIC = (1 << 3),
  OMP_CLAUSE_SCHEDULE_NONMONOTONIC = (1 << 4),
  OMP_CLAUSE_SCHEDULE_LAST = 2 * OMP_CLAUSE_SCHEDULE_NONMONOTONIC - 1
};

enum omp_clause_default_kind {
  OMP_CLAUSE_DEFAULT_UNSPECIFIED,
  OMP_CLAUSE_DEFAULT_SHARED,
  OMP_CLAUSE_DEFAULT_NONE,
  OMP_CLAUSE_DEFAULT_PRIVATE,
  OMP_CLAUSE_DEFAULT_FIRSTPRIVATE,
  OMP_CLAUSE_DEFAULT_LAST
};

/* There is a TYPE_QUAL value for each type qualifier.  They can be
   combined by bitwise-or to form the complete set of qualifiers for a
   type.  */
enum cv_qualifier {
  TYPE_UNQUALIFIED   = 0x0,
  TYPE_QUAL_CONST    = 0x1,
  TYPE_QUAL_VOLATILE = 0x2,
  TYPE_QUAL_RESTRICT = 0x4,
  TYPE_QUAL_ATOMIC   = 0x8
};

/* Standard named or nameless data types of the C compiler.  */
enum tree_index {
  TI_ERROR_MARK,
  TI_INTQI_TYPE,
  TI_INTHI_TYPE,
  TI_INTSI_TYPE,
  TI_INTDI_TYPE,
  TI_INTTI_TYPE,

  TI_UINTQI_TYPE,
  TI_UINTHI_TYPE,
  TI_UINTSI_TYPE,
  TI_UINTDI_TYPE,
  TI_UINTTI_TYPE,

  TI_ATOMICQI_TYPE,
  TI_ATOMICHI_TYPE,
  TI_ATOMICSI_TYPE,
  TI_ATOMICDI_TYPE,
  TI_ATOMICTI_TYPE,

  TI_UINT16_TYPE,
  TI_UINT32_TYPE,
  TI_UINT64_TYPE,

  TI_VOID,

  TI_INTEGER_ZERO,
  TI_INTEGER_ONE,
  TI_INTEGER_THREE,
  TI_INTEGER_MINUS_ONE,
  TI_NULL_POINTER,

  TI_SIZE_ZERO,
  TI_SIZE_ONE,

  TI_BITSIZE_ZERO,
  TI_BITSIZE_ONE,
  TI_BITSIZE_UNIT,

  TI_PUBLIC,
  TI_PROTECTED,
  TI_PRIVATE,

  TI_BOOLEAN_FALSE,
  TI_BOOLEAN_TRUE,

  TI_COMPLEX_INTEGER_TYPE,
  TI_COMPLEX_FLOAT_TYPE,
  TI_COMPLEX_DOUBLE_TYPE,
  TI_COMPLEX_LONG_DOUBLE_TYPE,

  TI_FLOAT_TYPE,
  TI_DOUBLE_TYPE,
  TI_LONG_DOUBLE_TYPE,

  TI_FLOAT_PTR_TYPE,
  TI_DOUBLE_PTR_TYPE,
  TI_LONG_DOUBLE_PTR_TYPE,
  TI_INTEGER_PTR_TYPE,

  TI_VOID_TYPE,
  TI_PTR_TYPE,
  TI_CONST_PTR_TYPE,
  TI_SIZE_TYPE,
  TI_PID_TYPE,
  TI_PTRDIFF_TYPE,
  TI_VA_LIST_TYPE,
  TI_VA_LIST_GPR_COUNTER_FIELD,
  TI_VA_LIST_FPR_COUNTER_FIELD,
  TI_BOOLEAN_TYPE,
  TI_FILEPTR_TYPE,
  TI_POINTER_SIZED_TYPE,

  TI_POINTER_BOUNDS_TYPE,

  TI_DFLOAT32_TYPE,
  TI_DFLOAT64_TYPE,
  TI_DFLOAT128_TYPE,
  TI_DFLOAT32_PTR_TYPE,
  TI_DFLOAT64_PTR_TYPE,
  TI_DFLOAT128_PTR_TYPE,

  TI_VOID_LIST_NODE,

  TI_MAIN_IDENTIFIER,

  TI_SAT_SFRACT_TYPE,
  TI_SAT_FRACT_TYPE,
  TI_SAT_LFRACT_TYPE,
  TI_SAT_LLFRACT_TYPE,
  TI_SAT_USFRACT_TYPE,
  TI_SAT_UFRACT_TYPE,
  TI_SAT_ULFRACT_TYPE,
  TI_SAT_ULLFRACT_TYPE,
  TI_SFRACT_TYPE,
  TI_FRACT_TYPE,
  TI_LFRACT_TYPE,
  TI_LLFRACT_TYPE,
  TI_USFRACT_TYPE,
  TI_UFRACT_TYPE,
  TI_ULFRACT_TYPE,
  TI_ULLFRACT_TYPE,
  TI_SAT_SACCUM_TYPE,
  TI_SAT_ACCUM_TYPE,
  TI_SAT_LACCUM_TYPE,
  TI_SAT_LLACCUM_TYPE,
  TI_SAT_USACCUM_TYPE,
  TI_SAT_UACCUM_TYPE,
  TI_SAT_ULACCUM_TYPE,
  TI_SAT_ULLACCUM_TYPE,
  TI_SACCUM_TYPE,
  TI_ACCUM_TYPE,
  TI_LACCUM_TYPE,
  TI_LLACCUM_TYPE,
  TI_USACCUM_TYPE,
  TI_UACCUM_TYPE,
  TI_ULACCUM_TYPE,
  TI_ULLACCUM_TYPE,
  TI_QQ_TYPE,
  TI_HQ_TYPE,
  TI_SQ_TYPE,
  TI_DQ_TYPE,
  TI_TQ_TYPE,
  TI_UQQ_TYPE,
  TI_UHQ_TYPE,
  TI_USQ_TYPE,
  TI_UDQ_TYPE,
  TI_UTQ_TYPE,
  TI_SAT_QQ_TYPE,
  TI_SAT_HQ_TYPE,
  TI_SAT_SQ_TYPE,
  TI_SAT_DQ_TYPE,
  TI_SAT_TQ_TYPE,
  TI_SAT_UQQ_TYPE,
  TI_SAT_UHQ_TYPE,
  TI_SAT_USQ_TYPE,
  TI_SAT_UDQ_TYPE,
  TI_SAT_UTQ_TYPE,
  TI_HA_TYPE,
  TI_SA_TYPE,
  TI_DA_TYPE,
  TI_TA_TYPE,
  TI_UHA_TYPE,
  TI_USA_TYPE,
  TI_UDA_TYPE,
  TI_UTA_TYPE,
  TI_SAT_HA_TYPE,
  TI_SAT_SA_TYPE,
  TI_SAT_DA_TYPE,
  TI_SAT_TA_TYPE,
  TI_SAT_UHA_TYPE,
  TI_SAT_USA_TYPE,
  TI_SAT_UDA_TYPE,
  TI_SAT_UTA_TYPE,

  TI_OPTIMIZATION_DEFAULT,
  TI_OPTIMIZATION_CURRENT,
  TI_TARGET_OPTION_DEFAULT,
  TI_TARGET_OPTION_CURRENT,
  TI_CURRENT_TARGET_PRAGMA,
  TI_CURRENT_OPTIMIZE_PRAGMA,

  TI_MAX
};

/* An enumeration of the standard C integer types.  These must be
   ordered so that shorter types appear before longer ones, and so
   that signed types appear before unsigned ones, for the correct
   functioning of interpret_integer() in c-lex.c.  */
enum integer_type_kind {
  itk_char,
  itk_signed_char,
  itk_unsigned_char,
  itk_short,
  itk_unsigned_short,
  itk_int,
  itk_unsigned_int,
  itk_long,
  itk_unsigned_long,
  itk_long_long,
  itk_unsigned_long_long,

  itk_intN_0,
  itk_unsigned_intN_0,
  itk_intN_1,
  itk_unsigned_intN_1,
  itk_intN_2,
  itk_unsigned_intN_2,
  itk_intN_3,
  itk_unsigned_intN_3,

  itk_none
};

/* A pointer-to-function member type looks like:

     struct {
       __P __pfn;
       ptrdiff_t __delta;
     };

   If __pfn is NULL, it is a NULL pointer-to-member-function.

   (Because the vtable is always the first thing in the object, we
   don't need its offset.)  If the function is virtual, then PFN is
   one plus twice the index into the vtable; otherwise, it is just a
   pointer to the function.

   Unfortunately, using the lowest bit of PFN doesn't work in
   architectures that don't impose alignment requirements on function
   addresses, or that use the lowest bit to tell one ISA from another,
   for example.  For such architectures, we use the lowest bit of
   DELTA instead of the lowest bit of the PFN, and DELTA will be
   multiplied by 2.  */
enum ptrmemfunc_vbit_where_t {
  ptrmemfunc_vbit_in_pfn,
  ptrmemfunc_vbit_in_delta
};

/* Flags that may be passed in the third argument of decl_attributes, and
   to handler functions for attributes.  */
enum attribute_flags {
  /* The type passed in is the type of a DECL, and any attributes that
     should be passed in again to be applied to the DECL rather than the
     type should be returned.  */
  ATTR_FLAG_DECL_NEXT = 1,
  /* The type passed in is a function return type, and any attributes that
     should be passed in again to be applied to the function type rather
     than the return type should be returned.  */
  ATTR_FLAG_FUNCTION_NEXT = 2,
  /* The type passed in is an array element type, and any attributes that
     should be passed in again to be applied to the array type rather
     than the element type should be returned.  */
  ATTR_FLAG_ARRAY_NEXT = 4,
  /* The type passed in is a structure, union or enumeration type being
     created, and should be modified in place.  */
  ATTR_FLAG_TYPE_IN_PLACE = 8,
  /* The attributes are being applied by default to a library function whose
     name indicates known behavior, and should be silently ignored if they
     are not in fact compatible with the function type.  */
  ATTR_FLAG_BUILT_IN = 16,
  /* A given attribute has been parsed as a C++-11 attribute.  */
  ATTR_FLAG_CXX11 = 32
};

/* Types used to represent sizes.  */
enum size_type_kind {
  stk_sizetype,		/* Normal representation of sizes in bytes.  */
  stk_ssizetype,	/* Signed representation of sizes in bytes.  */
  stk_bitsizetype,	/* Normal representation of sizes in bits.  */
  stk_sbitsizetype,	/* Signed representation of sizes in bits.  */
  stk_type_kind_last
};

enum operand_equal_flag {
  OEP_ONLY_CONST = 1,
  OEP_PURE_SAME = 2,
  OEP_MATCH_SIDE_EFFECTS = 4,
  OEP_ADDRESS_OF = 8
};

/* Enum and arrays used for tree allocation stats.
   Keep in sync with tree.c:tree_node_kind_names.  */
enum tree_node_kind {
  d_kind,
  t_kind,
  b_kind,
  s_kind,
  r_kind,
  e_kind,
  c_kind,
  id_kind,
  vec_kind,
  binfo_kind,
  ssa_name_kind,
  constr_kind,
  x_kind,
  lang_decl,
  lang_type,
  omp_clause_kind,
  all_kinds
};

enum annot_expr_kind {
  annot_expr_ivdep_kind,
  annot_expr_no_vector_kind,
  annot_expr_vector_kind,
  annot_expr_kind_last
};

/*---------------------------------------------------------------------------
                                Type definitions
---------------------------------------------------------------------------*/
/* When processing aliases at the symbol table level, we need the
   declaration of target. For this reason we need to queue aliases and
   process them after all declarations has been produced.  */
struct GTY(()) alias_pair {
  tree decl;
  tree target;
};

/* An initialization priority.  */
typedef unsigned short priority_type;

/* The type of a callback function for walking over tree structure.  */
typedef tree (*walk_tree_fn) (tree *, int *, void *);

/* The type of a callback function that represents a custom walk_tree.  */
typedef tree (*walk_tree_lh) (tree *, int *, tree (*) (tree *, int *, void *),
			      void *, hash_set<tree> *);


/*---------------------------------------------------------------------------
                              Main data structures
---------------------------------------------------------------------------*/
/* A tree node can represent a data type, a variable, an expression
   or a statement.  Each node has a TREE_CODE which says what kind of
   thing it represents.  Some common codes are:
   INTEGER_TYPE -- represents a type of integers.
   ARRAY_TYPE -- represents a type of pointer.
   VAR_DECL -- represents a declared variable.
   INTEGER_CST -- represents a constant integer value.
   PLUS_EXPR -- represents a sum (an expression).

   As for the contents of a tree node: there are some fields
   that all nodes share.  Each TREE_CODE has various special-purpose
   fields as well.  The fields of a node are never accessed directly,
   always through accessor macros.  */

/* Every kind of tree node starts with this structure,
   so all nodes have these fields.

   See the accessor macros, defined below, for documentation of the
   fields, and the table below which connects the fields and the
   accessor macros.  */

struct GTY(()) tree_base {
  ENUM_BITFIELD(tree_code) code : 16;

  unsigned side_effects_flag : 1;
  unsigned constant_flag : 1;
  unsigned addressable_flag : 1;
  unsigned volatile_flag : 1;
  unsigned readonly_flag : 1;
  unsigned asm_written_flag: 1;
  unsigned nowarning_flag : 1;
  unsigned visited : 1;

  unsigned used_flag : 1;
  unsigned nothrow_flag : 1;
  unsigned static_flag : 1;
  unsigned public_flag : 1;
  unsigned private_flag : 1;
  unsigned protected_flag : 1;
  unsigned deprecated_flag : 1;
  unsigned default_def_flag : 1;

  union {
    /* The bits in the following structure should only be used with
       accessor macros that constrain inputs with tree checking.  */
    struct {
      unsigned lang_flag_0 : 1;
      unsigned lang_flag_1 : 1;
      unsigned lang_flag_2 : 1;
      unsigned lang_flag_3 : 1;
      unsigned lang_flag_4 : 1;
      unsigned lang_flag_5 : 1;
      unsigned lang_flag_6 : 1;
      unsigned saturating_flag : 1;

      unsigned unsigned_flag : 1;
      unsigned packed_flag : 1;
      unsigned user_align : 1;
      unsigned nameless_flag : 1;
      unsigned atomic_flag : 1;
      unsigned spare0 : 3;

      unsigned spare1 : 8;

      /* This field is only used with TREE_TYPE nodes; the only reason it is
	 present in tree_base instead of tree_type is to save space.  The size
	 of the field must be large enough to hold addr_space_t values.  */
      unsigned address_space : 8;
    } bits;

    /* The following fields are present in tree_base to save space.  The
       nodes using them do not require any of the flags above and so can
       make better use of the 4-byte sized word.  */

    /* The number of HOST_WIDE_INTs in an INTEGER_CST.  */
    struct {
      /* The number of HOST_WIDE_INTs if the INTEGER_CST is accessed in
	 its native precision.  */
      unsigned char unextended;

      /* The number of HOST_WIDE_INTs if the INTEGER_CST is extended to
	 wider precisions based on its TYPE_SIGN.  */
      unsigned char extended;

      /* The number of HOST_WIDE_INTs if the INTEGER_CST is accessed in
	 offset_int precision, with smaller integers being extended
	 according to their TYPE_SIGN.  This is equal to one of the two
	 fields above but is cached for speed.  */
      unsigned char offset;
    } int_length;

    /* VEC length.  This field is only used with TREE_VEC.  */
    int length;

    /* SSA version number.  This field is only used with SSA_NAME.  */
    unsigned int version;

    /* Internal function code.  */
    enum internal_fn ifn;

    /* The following two fields are used for MEM_REF and TARGET_MEM_REF
       expression trees and specify known data non-dependences.  For
       two memory references in a function they are known to not
       alias if dependence_info.clique are equal and dependence_info.base
       are distinct.  */
    struct {
      unsigned short clique;
      unsigned short base;
    } dependence_info;
  } GTY((skip(""))) u;
};

/* The following table lists the uses of each of the above flags and
   for which types of nodes they are defined.

   addressable_flag:

       TREE_ADDRESSABLE in
           VAR_DECL, PARM_DECL, RESULT_DECL, FUNCTION_DECL, LABEL_DECL
           SSA_NAME
           all types
           CONSTRUCTOR, IDENTIFIER_NODE
           STMT_EXPR

       CALL_EXPR_TAILCALL in
           CALL_EXPR

       CASE_LOW_SEEN in
           CASE_LABEL_EXPR

       PREDICT_EXPR_OUTCOME in
	   PREDICT_EXPR

   static_flag:

       TREE_STATIC in
           VAR_DECL, FUNCTION_DECL
           CONSTRUCTOR

       TREE_NO_TRAMPOLINE in
           ADDR_EXPR

       BINFO_VIRTUAL_P in
           TREE_BINFO

       TREE_SYMBOL_REFERENCED in
           IDENTIFIER_NODE

       CLEANUP_EH_ONLY in
           TARGET_EXPR, WITH_CLEANUP_EXPR

       TRY_CATCH_IS_CLEANUP in
           TRY_CATCH_EXPR

       ASM_INPUT_P in
           ASM_EXPR

       TYPE_REF_CAN_ALIAS_ALL in
           POINTER_TYPE, REFERENCE_TYPE

       CASE_HIGH_SEEN in
           CASE_LABEL_EXPR

       ENUM_IS_SCOPED in
	   ENUMERAL_TYPE

       TRANSACTION_EXPR_OUTER in
	   TRANSACTION_EXPR

       SSA_NAME_ANTI_RANGE_P in
	   SSA_NAME

   public_flag:

       TREE_OVERFLOW in
           INTEGER_CST, REAL_CST, COMPLEX_CST, VECTOR_CST

       TREE_PUBLIC in
           VAR_DECL, FUNCTION_DECL
           IDENTIFIER_NODE

       CONSTRUCTOR_NO_CLEARING in
           CONSTRUCTOR

       ASM_VOLATILE_P in
           ASM_EXPR

       CALL_EXPR_VA_ARG_PACK in
           CALL_EXPR

       TYPE_CACHED_VALUES_P in
           all types

       SAVE_EXPR_RESOLVED_P in
           SAVE_EXPR

       OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE in
           OMP_CLAUSE_LASTPRIVATE

       OMP_CLAUSE_PRIVATE_DEBUG in
           OMP_CLAUSE_PRIVATE

       OMP_CLAUSE_LINEAR_NO_COPYIN in
	   OMP_CLAUSE_LINEAR

       OMP_CLAUSE_MAP_ZERO_BIAS_ARRAY_SECTION in
	   OMP_CLAUSE_MAP

       OMP_CLAUSE_REDUCTION_OMP_ORIG_REF in
	   OMP_CLAUSE_REDUCTION

       TRANSACTION_EXPR_RELAXED in
	   TRANSACTION_EXPR

   private_flag:

       TREE_PRIVATE in
           all decls

       CALL_EXPR_RETURN_SLOT_OPT in
           CALL_EXPR

       OMP_SECTION_LAST in
           OMP_SECTION

       OMP_PARALLEL_COMBINED in
           OMP_PARALLEL

       OMP_ATOMIC_SEQ_CST in
	   OMP_ATOMIC*

       OMP_CLAUSE_PRIVATE_OUTER_REF in
	   OMP_CLAUSE_PRIVATE

       OMP_CLAUSE_LINEAR_NO_COPYOUT in
	   OMP_CLAUSE_LINEAR

       TYPE_REF_IS_RVALUE in
	   REFERENCE_TYPE

       ENUM_IS_OPAQUE in
	   ENUMERAL_TYPE

   protected_flag:

       TREE_PROTECTED in
           BLOCK
           all decls

       CALL_FROM_THUNK_P and
       CALL_ALLOCA_FOR_VAR_P in
           CALL_EXPR

       OMP_CLAUSE_LINEAR_VARIABLE_STRIDE in
	   OMP_CLAUSE_LINEAR

   side_effects_flag:

       TREE_SIDE_EFFECTS in
           all expressions
           all decls
           all constants

       FORCED_LABEL in
           LABEL_DECL

   volatile_flag:

       TREE_THIS_VOLATILE in
           all expressions
           all decls

       TYPE_VOLATILE in
           all types

   readonly_flag:

       TREE_READONLY in
           all expressions
           all decls

       TYPE_READONLY in
           all types

   constant_flag:

       TREE_CONSTANT in
           all expressions
           all decls
           all constants

       TYPE_SIZES_GIMPLIFIED in
           all types

   unsigned_flag:

       TYPE_UNSIGNED in
           all types

       DECL_UNSIGNED in
           all decls

   asm_written_flag:

       TREE_ASM_WRITTEN in
           VAR_DECL, FUNCTION_DECL, TYPE_DECL
           RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE
           BLOCK, STRING_CST

       SSA_NAME_OCCURS_IN_ABNORMAL_PHI in
           SSA_NAME

   used_flag:

       TREE_USED in
           all expressions
           all decls
           IDENTIFIER_NODE

   nothrow_flag:

       TREE_NOTHROW in
           CALL_EXPR
           FUNCTION_DECL

       TYPE_ALIGN_OK in
           all types

       TREE_THIS_NOTRAP in
          INDIRECT_REF, MEM_REF, TARGET_MEM_REF, ARRAY_REF, ARRAY_RANGE_REF

       SSA_NAME_IN_FREE_LIST in
          SSA_NAME

       DECL_NONALIASED in
	  VAR_DECL

   deprecated_flag:

       TREE_DEPRECATED in
           all decls
	   all types

       IDENTIFIER_TRANSPARENT_ALIAS in
           IDENTIFIER_NODE

   visited:

       TREE_VISITED in
           all trees (used liberally by many passes)

   saturating_flag:

       TYPE_REVERSE_STORAGE_ORDER in
           RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE, ARRAY_TYPE

       TYPE_SATURATING in
           other types

       VAR_DECL_IS_VIRTUAL_OPERAND in
	   VAR_DECL

   nowarning_flag:

       TREE_NO_WARNING in
           all expressions
           all decls

       TYPE_ARTIFICIAL in
           all types

   default_def_flag:

       TYPE_FINAL_P in
	   RECORD_TYPE, UNION_TYPE and QUAL_UNION_TYPE

       TYPE_VECTOR_OPAQUE in
	   VECTOR_TYPE

       SSA_NAME_IS_DEFAULT_DEF in
           SSA_NAME

       DECL_NONLOCAL_FRAME in
	   VAR_DECL

       REF_REVERSE_STORAGE_ORDER in
           BIT_FIELD_REF, MEM_REF
*/

struct GTY(()) tree_typed {
  struct tree_base base;
  tree type;
};

struct GTY(()) tree_common {
  struct tree_typed typed;
  tree chain;
};

struct GTY(()) tree_int_cst {
  struct tree_typed typed;
  HOST_WIDE_INT val[1];
};


struct GTY(()) tree_real_cst {
  struct tree_typed typed;
  struct real_value * real_cst_ptr;
};

struct GTY(()) tree_fixed_cst {
  struct tree_typed typed;
  struct fixed_value * fixed_cst_ptr;
};

struct GTY(()) tree_string {
  struct tree_typed typed;
  int length;
  char str[1];
};

struct GTY(()) tree_complex {
  struct tree_typed typed;
  tree real;
  tree imag;
};

struct GTY(()) tree_vector {
  struct tree_typed typed;
  tree GTY ((length ("TYPE_VECTOR_SUBPARTS (TREE_TYPE ((tree)&%h))"))) elts[1];
};

struct GTY(()) tree_identifier {
  struct tree_common common;
  struct ht_identifier id;
};

struct GTY(()) tree_list {
  struct tree_common common;
  tree purpose;
  tree value;
};

struct GTY(()) tree_vec {
  struct tree_common common;
  tree GTY ((length ("TREE_VEC_LENGTH ((tree)&%h)"))) a[1];
};

/* A single element of a CONSTRUCTOR. VALUE holds the actual value of the
   element. INDEX can optionally design the position of VALUE: in arrays,
   it is the index where VALUE has to be placed; in structures, it is the
   FIELD_DECL of the member.  */
struct GTY(()) constructor_elt {
  tree index;
  tree value;
};

struct GTY(()) tree_constructor {
  struct tree_typed typed;
  vec<constructor_elt, va_gc> *elts;
};

enum omp_clause_depend_kind
{
  OMP_CLAUSE_DEPEND_IN,
  OMP_CLAUSE_DEPEND_OUT,
  OMP_CLAUSE_DEPEND_INOUT,
  OMP_CLAUSE_DEPEND_SOURCE,
  OMP_CLAUSE_DEPEND_SINK,
  OMP_CLAUSE_DEPEND_LAST
};

enum omp_clause_proc_bind_kind
{
  /* Numbers should match omp_proc_bind_t enum in omp.h.  */
  OMP_CLAUSE_PROC_BIND_FALSE = 0,
  OMP_CLAUSE_PROC_BIND_TRUE = 1,
  OMP_CLAUSE_PROC_BIND_MASTER = 2,
  OMP_CLAUSE_PROC_BIND_CLOSE = 3,
  OMP_CLAUSE_PROC_BIND_SPREAD = 4,
  OMP_CLAUSE_PROC_BIND_LAST
};

enum omp_clause_linear_kind
{
  OMP_CLAUSE_LINEAR_DEFAULT,
  OMP_CLAUSE_LINEAR_REF,
  OMP_CLAUSE_LINEAR_VAL,
  OMP_CLAUSE_LINEAR_UVAL
};

struct GTY(()) tree_exp {
  struct tree_typed typed;
  location_t locus;
  tree GTY ((special ("tree_exp"),
	     desc ("TREE_CODE ((tree) &%0)")))
    operands[1];
};

/* Immediate use linking structure.  This structure is used for maintaining
   a doubly linked list of uses of an SSA_NAME.  */
struct GTY(()) ssa_use_operand_t {
  struct ssa_use_operand_t* GTY((skip(""))) prev;
  struct ssa_use_operand_t* GTY((skip(""))) next;
  /* Immediate uses for a given SSA name are maintained as a cyclic
     list.  To recognize the root of this list, the location field
     needs to point to the original SSA name.  Since statements and
     SSA names are of different data types, we need this union.  See
     the explanation in struct imm_use_iterator.  */
  union { gimple *stmt; tree ssa_name; } GTY((skip(""))) loc;
  tree *GTY((skip(""))) use;
};

struct GTY(()) tree_ssa_name {
  struct tree_typed typed;

  /* _DECL wrapped by this SSA name.  */
  tree var;

  /* Statement that defines this SSA name.  */
  gimple *def_stmt;

  /* Value range information.  */
  union ssa_name_info_type {
    /* Pointer attributes used for alias analysis.  */
    struct GTY ((tag ("0"))) ptr_info_def *ptr_info;
    /* Value range attributes used for zero/sign extension elimination.  */
    struct GTY ((tag ("1"))) range_info_def *range_info;
  } GTY ((desc ("%1.typed.type ?" \
		"!POINTER_TYPE_P (TREE_TYPE ((tree)&%1)) : 2"))) info;

  /* Immediate uses list for this SSA_NAME.  */
  struct ssa_use_operand_t imm_uses;
};

struct GTY(()) phi_arg_d {
  /* imm_use MUST be the first element in struct because we do some
     pointer arithmetic with it.  See phi_arg_index_from_use.  */
  struct ssa_use_operand_t imm_use;
  tree def;
  location_t locus;
};

struct GTY(()) tree_omp_clause {
  struct tree_common common;
  location_t locus;
  enum omp_clause_code code;
  union omp_clause_subcode {
    enum omp_clause_default_kind   default_kind;
    enum omp_clause_schedule_kind  schedule_kind;
    enum omp_clause_depend_kind    depend_kind;
    /* See include/gomp-constants.h for enum gomp_map_kind's values.  */
    unsigned int		   map_kind;
    enum omp_clause_proc_bind_kind proc_bind_kind;
    enum tree_code                 reduction_code;
    enum omp_clause_linear_kind    linear_kind;
    enum tree_code                 if_modifier;
    /* The dimension a OMP_CLAUSE__GRIDDIM_ clause of a gridified target
       construct describes.  */
    unsigned int		   dimension;
  } GTY ((skip)) subcode;

  /* The gimplification of OMP_CLAUSE_REDUCTION_{INIT,MERGE} for omp-low's
     usage.  */
  gimple_seq gimple_reduction_init;
  gimple_seq gimple_reduction_merge;

  tree GTY ((length ("omp_clause_num_ops[OMP_CLAUSE_CODE ((tree)&%h)]")))
    ops[1];
};

struct GTY(()) tree_block {
  struct tree_base base;
  tree chain;

  unsigned abstract_flag : 1;
  unsigned block_num : 31;

  location_t locus;
  location_t end_locus;

  tree vars;
  vec<tree, va_gc> *nonlocalized_vars;

  tree subblocks;
  tree supercontext;
  tree abstract_origin;
  tree fragment_origin;
  tree fragment_chain;

  /* Pointer to the DWARF lexical block.  */
  struct die_struct *die;
};

struct GTY(()) tree_type_common {
  struct tree_common common;
  tree size;
  tree size_unit;
  tree attributes;
  unsigned int uid;

  unsigned int precision : 10;
  unsigned no_force_blk_flag : 1;
  unsigned needs_constructing_flag : 1;
  unsigned transparent_aggr_flag : 1;
  unsigned restrict_flag : 1;
  unsigned contains_placeholder_bits : 2;

  ENUM_BITFIELD(machine_mode) mode : 8;

  unsigned string_flag : 1;
  unsigned lang_flag_0 : 1;
  unsigned lang_flag_1 : 1;
  unsigned lang_flag_2 : 1;
  unsigned lang_flag_3 : 1;
  unsigned lang_flag_4 : 1;
  unsigned lang_flag_5 : 1;
  unsigned lang_flag_6 : 1;

  unsigned int align;
  alias_set_type alias_set;
  tree pointer_to;
  tree reference_to;
  union tree_type_symtab {
    int GTY ((tag ("TYPE_SYMTAB_IS_ADDRESS"))) address;
    const char * GTY ((tag ("TYPE_SYMTAB_IS_POINTER"))) pointer;
    struct die_struct * GTY ((tag ("TYPE_SYMTAB_IS_DIE"))) die;
  } GTY ((desc ("debug_hooks->tree_type_symtab_field"))) symtab;
  tree canonical;
  tree next_variant;
  tree main_variant;
  tree context;
  tree name;
};

struct GTY(()) tree_type_with_lang_specific {
  struct tree_type_common common;
  /* Points to a structure whose details depend on the language in use.  */
  struct lang_type *lang_specific;
};

struct GTY(()) tree_type_non_common {
  struct tree_type_with_lang_specific with_lang_specific;
  tree values;
  tree minval;
  tree maxval;
  tree binfo;
};

struct GTY (()) tree_binfo {
  struct tree_common common;

  tree offset;
  tree vtable;
  tree virtuals;
  tree vptr_field;
  vec<tree, va_gc> *base_accesses;
  tree inheritance;

  tree vtt_subvtt;
  tree vtt_vptr;

  vec<tree, va_gc> base_binfos;
};

struct GTY(()) tree_decl_minimal {
  struct tree_common common;
  location_t locus;
  unsigned int uid;
  tree name;
  tree context;
};

struct GTY(()) tree_decl_common {
  struct tree_decl_minimal common;
  tree size;

  ENUM_BITFIELD(machine_mode) mode : 8;

  unsigned nonlocal_flag : 1;
  unsigned virtual_flag : 1;
  unsigned ignored_flag : 1;
  unsigned abstract_flag : 1;
  unsigned artificial_flag : 1;
  unsigned preserve_flag: 1;
  unsigned debug_expr_is_from : 1;

  unsigned lang_flag_0 : 1;
  unsigned lang_flag_1 : 1;
  unsigned lang_flag_2 : 1;
  unsigned lang_flag_3 : 1;
  unsigned lang_flag_4 : 1;
  unsigned lang_flag_5 : 1;
  unsigned lang_flag_6 : 1;
  unsigned lang_flag_7 : 1;
  unsigned lang_flag_8 : 1;

  /* In VAR_DECL and PARM_DECL, this is DECL_REGISTER.  */
  unsigned decl_flag_0 : 1;
  /* In FIELD_DECL, this is DECL_BIT_FIELD
     In VAR_DECL and FUNCTION_DECL, this is DECL_EXTERNAL.
     In TYPE_DECL, this is TYPE_DECL_SUPPRESS_DEBUG.  */
  unsigned decl_flag_1 : 1;
  /* In FIELD_DECL, this is DECL_NONADDRESSABLE_P
     In VAR_DECL, PARM_DECL and RESULT_DECL, this is
     DECL_HAS_VALUE_EXPR_P.  */
  unsigned decl_flag_2 : 1;
  /* 1 bit unused.  */
  unsigned decl_flag_3 : 1;
  /* Logically, these two would go in a theoretical base shared by var and
     parm decl. */
  unsigned gimple_reg_flag : 1;
  /* In VAR_DECL, PARM_DECL and RESULT_DECL, this is DECL_BY_REFERENCE.  */
  unsigned decl_by_reference_flag : 1;
  /* In a VAR_DECL and PARM_DECL, this is DECL_READ_P.  */
  unsigned decl_read_flag : 1;
  /* In a VAR_DECL or RESULT_DECL, this is DECL_NONSHAREABLE.  */
  unsigned decl_nonshareable_flag : 1;

  /* DECL_OFFSET_ALIGN, used only for FIELD_DECLs.  */
  unsigned int off_align : 8;

  /* 24 bits unused.  */

  /* DECL_ALIGN.  It should have the same size as TYPE_ALIGN.  */
  unsigned int align;

  /* UID for points-to sets, stable over copying from inlining.  */
  unsigned int pt_uid;

  tree size_unit;
  tree initial;
  tree attributes;
  tree abstract_origin;

  /* Points to a structure whose details depend on the language in use.  */
  struct lang_decl *lang_specific;
};

struct GTY(()) tree_decl_with_rtl {
  struct tree_decl_common common;
  rtx rtl;
};

struct GTY(()) tree_field_decl {
  struct tree_decl_common common;

  tree offset;
  tree bit_field_type;
  tree qualifier;
  tree bit_offset;
  tree fcontext;
};

struct GTY(()) tree_label_decl {
  struct tree_decl_with_rtl common;
  int label_decl_uid;
  int eh_landing_pad_nr;
};

struct GTY(()) tree_result_decl {
  struct tree_decl_with_rtl common;
};

struct GTY(()) tree_const_decl {
  struct tree_decl_common common;
};

struct GTY(()) tree_parm_decl {
  struct tree_decl_with_rtl common;
  rtx incoming_rtl;
};

struct GTY(()) tree_decl_with_vis {
 struct tree_decl_with_rtl common;
 tree assembler_name;
 struct symtab_node *symtab_node;

 /* Belong to VAR_DECL exclusively.  */
 unsigned defer_output : 1;
 unsigned hard_register : 1;
 unsigned common_flag : 1;
 unsigned in_text_section : 1;
 unsigned in_constant_pool : 1;
 unsigned dllimport_flag : 1;
 /* Don't belong to VAR_DECL exclusively.  */
 unsigned weak_flag : 1;

 unsigned seen_in_bind_expr : 1;
 unsigned comdat_flag : 1;
 /* Used for FUNCTION_DECL, VAR_DECL and in C++ for TYPE_DECL.  */
 ENUM_BITFIELD(symbol_visibility) visibility : 2;
 unsigned visibility_specified : 1;

 /* Belong to FUNCTION_DECL exclusively.  */
 unsigned init_priority_p : 1;
 /* Used by C++ only.  Might become a generic decl flag.  */
 unsigned shadowed_for_var_p : 1;
 /* Belong to FUNCTION_DECL exclusively.  */
 unsigned cxx_constructor : 1;
 /* Belong to FUNCTION_DECL exclusively.  */
 unsigned cxx_destructor : 1;
 /* Belong to FUNCTION_DECL exclusively.  */
 unsigned final : 1;
 /* Belong to FUNCTION_DECL exclusively.  */
 unsigned regdecl_flag : 1;
 /* 14 unused bits. */
};

struct GTY(()) tree_var_decl {
  struct tree_decl_with_vis common;
};

struct GTY(()) tree_decl_non_common {
  struct tree_decl_with_vis common;
  /* Almost all FE's use this.  */
  tree result;
};

/* FUNCTION_DECL inherits from DECL_NON_COMMON because of the use of the
   arguments/result/saved_tree fields by front ends.   It was either inherit
   FUNCTION_DECL from non_common, or inherit non_common from FUNCTION_DECL,
   which seemed a bit strange.  */

struct GTY(()) tree_function_decl {
  struct tree_decl_non_common common;

  struct function *f;

  /* Arguments of the function.  */
  tree arguments;
  /* The personality function. Used for stack unwinding. */
  tree personality;

  /* Function specific options that are used by this function.  */
  tree function_specific_target;	/* target options */
  tree function_specific_optimization;	/* optimization options */

  /* Generic function body.  */
  tree saved_tree;
  /* Index within a virtual table.  */
  tree vindex;

  /* In a FUNCTION_DECL for which DECL_BUILT_IN holds, this is
     DECL_FUNCTION_CODE.  Otherwise unused.
     ???  The bitfield needs to be able to hold all target function
	  codes as well.  */
  ENUM_BITFIELD(built_in_function) function_code : 12;
  ENUM_BITFIELD(built_in_class) built_in_class : 2;

  unsigned static_ctor_flag : 1;
  unsigned static_dtor_flag : 1;

  unsigned uninlinable : 1;
  unsigned possibly_inlined : 1;
  unsigned novops_flag : 1;
  unsigned returns_twice_flag : 1;
  unsigned malloc_flag : 1;
  unsigned operator_new_flag : 1;
  unsigned declared_inline_flag : 1;
  unsigned no_inline_warning_flag : 1;

  unsigned no_instrument_function_entry_exit : 1;
  unsigned no_limit_stack : 1;
  unsigned disregard_inline_limits : 1;
  unsigned pure_flag : 1;
  unsigned looping_const_or_pure_flag : 1;
  unsigned has_debug_args_flag : 1;
  unsigned tm_clone_flag : 1;
  unsigned versioned_function : 1;
  /* No bits left.  */
};

struct GTY(()) tree_translation_unit_decl {
  struct tree_decl_common common;
  /* Source language of this translation unit.  Used for DWARF output.  */
  const char * GTY((skip(""))) language;
  /* TODO: Non-optimization used to build this translation unit.  */
  /* TODO: Root of a partial DWARF tree for global types and decls.  */
};

struct GTY(()) tree_type_decl {
  struct tree_decl_non_common common;

};

struct GTY ((chain_next ("%h.next"), chain_prev ("%h.prev"))) tree_statement_list_node
 {
  struct tree_statement_list_node *prev;
  struct tree_statement_list_node *next;
  tree stmt;
};

struct GTY(()) tree_statement_list
 {
  struct tree_typed typed;
  struct tree_statement_list_node *head;
  struct tree_statement_list_node *tail;
};


/* Optimization options used by a function.  */

struct GTY(()) tree_optimization_option {
  struct tree_common common;

  /* The optimization options used by the user.  */
  struct cl_optimization *opts;

  /* Target optabs for this set of optimization options.  This is of
     type `struct target_optabs *'.  */
  void *GTY ((atomic)) optabs;

  /* The value of this_target_optabs against which the optabs above were
     generated.  */
  struct target_optabs *GTY ((skip)) base_optabs;
};

/* Forward declaration, defined in target-globals.h.  */

struct GTY(()) target_globals;

/* Target options used by a function.  */

struct GTY(()) tree_target_option {
  struct tree_common common;

  /* Target globals for the corresponding target option.  */
  struct target_globals *globals;

  /* The optimization options used by the user.  */
  struct cl_target_option *opts;
};

/* Define the overall contents of a tree node.
   It may be any of the structures declared above
   for various types of node.  */
union GTY ((ptr_alias (union lang_tree_node),
	    desc ("tree_node_structure (&%h)"), variable_size)) tree_node {
  struct tree_base GTY ((tag ("TS_BASE"))) base;
  struct tree_typed GTY ((tag ("TS_TYPED"))) typed;
  struct tree_common GTY ((tag ("TS_COMMON"))) common;
  struct tree_int_cst GTY ((tag ("TS_INT_CST"))) int_cst;
  struct tree_real_cst GTY ((tag ("TS_REAL_CST"))) real_cst;
  struct tree_fixed_cst GTY ((tag ("TS_FIXED_CST"))) fixed_cst;
  struct tree_vector GTY ((tag ("TS_VECTOR"))) vector;
  struct tree_string GTY ((tag ("TS_STRING"))) string;
  struct tree_complex GTY ((tag ("TS_COMPLEX"))) complex;
  struct tree_identifier GTY ((tag ("TS_IDENTIFIER"))) identifier;
  struct tree_decl_minimal GTY((tag ("TS_DECL_MINIMAL"))) decl_minimal;
  struct tree_decl_common GTY ((tag ("TS_DECL_COMMON"))) decl_common;
  struct tree_decl_with_rtl GTY ((tag ("TS_DECL_WRTL"))) decl_with_rtl;
  struct tree_decl_non_common  GTY ((tag ("TS_DECL_NON_COMMON")))
    decl_non_common;
  struct tree_parm_decl  GTY  ((tag ("TS_PARM_DECL"))) parm_decl;
  struct tree_decl_with_vis GTY ((tag ("TS_DECL_WITH_VIS"))) decl_with_vis;
  struct tree_var_decl GTY ((tag ("TS_VAR_DECL"))) var_decl;
  struct tree_field_decl GTY ((tag ("TS_FIELD_DECL"))) field_decl;
  struct tree_label_decl GTY ((tag ("TS_LABEL_DECL"))) label_decl;
  struct tree_result_decl GTY ((tag ("TS_RESULT_DECL"))) result_decl;
  struct tree_const_decl GTY ((tag ("TS_CONST_DECL"))) const_decl;
  struct tree_type_decl GTY ((tag ("TS_TYPE_DECL"))) type_decl;
  struct tree_function_decl GTY ((tag ("TS_FUNCTION_DECL"))) function_decl;
  struct tree_translation_unit_decl GTY ((tag ("TS_TRANSLATION_UNIT_DECL")))
    translation_unit_decl;
  struct tree_type_common GTY ((tag ("TS_TYPE_COMMON"))) type_common;
  struct tree_type_with_lang_specific GTY ((tag ("TS_TYPE_WITH_LANG_SPECIFIC")))
    type_with_lang_specific;
  struct tree_type_non_common GTY ((tag ("TS_TYPE_NON_COMMON")))
    type_non_common;
  struct tree_list GTY ((tag ("TS_LIST"))) list;
  struct tree_vec GTY ((tag ("TS_VEC"))) vec;
  struct tree_exp GTY ((tag ("TS_EXP"))) exp;
  struct tree_ssa_name GTY ((tag ("TS_SSA_NAME"))) ssa_name;
  struct tree_block GTY ((tag ("TS_BLOCK"))) block;
  struct tree_binfo GTY ((tag ("TS_BINFO"))) binfo;
  struct tree_statement_list GTY ((tag ("TS_STATEMENT_LIST"))) stmt_list;
  struct tree_constructor GTY ((tag ("TS_CONSTRUCTOR"))) constructor;
  struct tree_omp_clause GTY ((tag ("TS_OMP_CLAUSE"))) omp_clause;
  struct tree_optimization_option GTY ((tag ("TS_OPTIMIZATION"))) optimization;
  struct tree_target_option GTY ((tag ("TS_TARGET_OPTION"))) target_option;
};

/* Structure describing an attribute and a function to handle it.  */
struct attribute_spec {
  /* The name of the attribute (without any leading or trailing __),
     or NULL to mark the end of a table of attributes.  */
  const char *name;
  /* The minimum length of the list of arguments of the attribute.  */
  int min_length;
  /* The maximum length of the list of arguments of the attribute
     (-1 for no maximum).  */
  int max_length;
  /* Whether this attribute requires a DECL.  If it does, it will be passed
     from types of DECLs, function return types and array element types to
     the DECLs, function types and array types respectively; but when
     applied to a type in any other circumstances, it will be ignored with
     a warning.  (If greater control is desired for a given attribute,
     this should be false, and the flags argument to the handler may be
     used to gain greater control in that case.)  */
  bool decl_required;
  /* Whether this attribute requires a type.  If it does, it will be passed
     from a DECL to the type of that DECL.  */
  bool type_required;
  /* Whether this attribute requires a function (or method) type.  If it does,
     it will be passed from a function pointer type to the target type,
     and from a function return type (which is not itself a function
     pointer type) to the function type.  */
  bool function_type_required;
  /* Function to handle this attribute.  NODE points to the node to which
     the attribute is to be applied.  If a DECL, it should be modified in
     place; if a TYPE, a copy should be created.  NAME is the name of the
     attribute (possibly with leading or trailing __).  ARGS is the TREE_LIST
     of the arguments (which may be NULL).  FLAGS gives further information
     about the context of the attribute.  Afterwards, the attributes will
     be added to the DECL_ATTRIBUTES or TYPE_ATTRIBUTES, as appropriate,
     unless *NO_ADD_ATTRS is set to true (which should be done on error,
     as well as in any other cases when the attributes should not be added
     to the DECL or TYPE).  Depending on FLAGS, any attributes to be
     applied to another type or DECL later may be returned;
     otherwise the return value should be NULL_TREE.  This pointer may be
     NULL if no special handling is required beyond the checks implied
     by the rest of this structure.  */
  tree (*handler) (tree *node, tree name, tree args,
		   int flags, bool *no_add_attrs);
  /* Specifies if attribute affects type's identity.  */
  bool affects_type_identity;
};

/* These functions allow a front-end to perform a manual layout of a
   RECORD_TYPE.  (For instance, if the placement of subsequent fields
   depends on the placement of fields so far.)  Begin by calling
   start_record_layout.  Then, call place_field for each of the
   fields.  Then, call finish_record_layout.  See layout_type for the
   default way in which these functions are used.  */
typedef struct record_layout_info_s {
  /* The RECORD_TYPE that we are laying out.  */
  tree t;
  /* The offset into the record so far, in bytes, not including bits in
     BITPOS.  */
  tree offset;
  /* The last known alignment of SIZE.  */
  unsigned int offset_align;
  /* The bit position within the last OFFSET_ALIGN bits, in bits.  */
  tree bitpos;
  /* The alignment of the record so far, in bits.  */
  unsigned int record_align;
  /* The alignment of the record so far, ignoring #pragma pack and
     __attribute__ ((packed)), in bits.  */
  unsigned int unpacked_align;
  /* The previous field laid out.  */
  tree prev_field;
  /* The static variables (i.e., class variables, as opposed to
     instance variables) encountered in T.  */
  vec<tree, va_gc> *pending_statics;
  /* Bits remaining in the current alignment group */
  int remaining_in_alignment;
  /* True if we've seen a packed field that didn't have normal
     alignment anyway.  */
  int packed_maybe_necessary;
} *record_layout_info;

/* Iterator for going through the function arguments.  */
struct function_args_iterator {
  tree next;			/* TREE_LIST pointing to the next argument */
};

/* Structures to map from a tree to another tree.  */
struct GTY(()) tree_map_base {
  tree from;
};

/* Map from a tree to another tree.  */

struct GTY((for_user)) tree_map {
  struct tree_map_base base;
  unsigned int hash;
  tree to;
};

/* Map from a decl tree to another tree.  */
struct GTY((for_user)) tree_decl_map {
  struct tree_map_base base;
  tree to;
};

/* Map from a tree to an int.  */
struct GTY((for_user)) tree_int_map {
  struct tree_map_base base;
  unsigned int to;
};

/* Map from a decl tree to a tree vector.  */
struct GTY((for_user)) tree_vec_map {
  struct tree_map_base base;
  vec<tree, va_gc> *to;
};

/* Abstract iterators for CALL_EXPRs.  These static inline definitions
   have to go towards the end of tree.h so that union tree_node is fully
   defined by this point.  */

/* Structure containing iterator state.  */
struct call_expr_arg_iterator {
  tree t;	/* the call_expr */
  int n;	/* argument count */
  int i;	/* next argument index */
};

struct const_call_expr_arg_iterator {
  const_tree t;	/* the call_expr */
  int n;	/* argument count */
  int i;	/* next argument index */
};

/* The builtin_info structure holds the FUNCTION_DECL of the standard builtin
   function, and flags.  */
struct GTY(()) builtin_info_type {
  tree decl;
  /* Whether the user can use <xxx> instead of explicitly using calls
     to __builtin_<xxx>.  */
  unsigned implicit_p : 1;
  /* Whether the user has provided a declaration of <xxx>.  */
  unsigned declared_p : 1;
};


/*---------------------------------------------------------------------------
                                Global variables
---------------------------------------------------------------------------*/
/* Matrix describing the structures contained in a given tree code.  */
extern unsigned char tree_contains_struct[MAX_TREE_CODES][64];

/* Class of tree given its code.  */
extern const enum tree_code_class tree_code_type[];

/* Each tree code class has an associated string representation.
   These must correspond to the tree_code_class entries.  */
extern const char *const tree_code_class_strings[];

/* Number of argument-words in each kind of tree-node.  */
extern const unsigned char tree_code_length[];

/* Vector of all alias pairs for global symbols.  */
extern GTY(()) vec<alias_pair, va_gc> *alias_pairs;

/* Names of all the built_in classes.  */
extern const char *const built_in_class_names[BUILT_IN_LAST];

/* Names of all the built_in functions.  */
extern const char * built_in_names[(int) END_BUILTINS];

/* Number of operands and names for each OMP_CLAUSE node.  */
extern unsigned const char omp_clause_num_ops[];
extern const char * const omp_clause_code_name[];

/* A vector of all translation-units.  */
extern GTY (()) vec<tree, va_gc> *all_translation_units;

/* Vector of standard trees used by the C compiler.  */
extern GTY(()) tree global_trees[TI_MAX];

/* The standard C integer types.  Use integer_type_kind to index into
   this array.  */
extern GTY(()) tree integer_types[itk_none];

/* Types used to represent sizes.  */
extern GTY(()) tree sizetype_tab[(int) stk_type_kind_last];

/* Arrays for keeping track of tree node statistics.  */
extern int tree_node_counts[];
extern int tree_node_sizes[];

/* True if we are in gimple form and the actions of the folders need to
   be restricted.  False if we are not in gimple form and folding is not
   restricted to creating gimple expressions.  */
extern bool in_gimple_form;

/* Functional interface to the builtin functions.  */
extern GTY(()) builtin_info_type builtin_info[(int)END_BUILTINS];

/* If nonzero, an upper limit on alignment of structure fields, in bits,  */
extern unsigned int maximum_field_alignment;

/* Points to the FUNCTION_DECL of the function whose body we are reading.  */
extern GTY(()) tree current_function_decl;

/* Nonzero means a FUNC_BEGIN label was emitted.  */
extern GTY(()) const char * current_function_func_begin_label;

#endif  // GCC_TREE_CORE_H