reference, declarationdefinition
definition → references, declarations, derived classes, virtual overrides
reference to multiple definitions → definitions
unreferenced
    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
 2016
 2017
 2018
 2019
 2020
 2021
 2022
 2023
 2024
 2025
 2026
 2027
 2028
 2029
 2030
 2031
 2032
 2033
 2034
 2035
 2036
 2037
 2038
 2039
 2040
 2041
 2042
 2043
 2044
 2045
 2046
 2047
 2048
 2049
 2050
 2051
 2052
 2053
 2054
 2055
 2056
 2057
 2058
 2059
 2060
 2061
 2062
 2063
 2064
 2065
 2066
 2067
 2068
 2069
 2070
 2071
 2072
 2073
 2074
 2075
 2076
 2077
 2078
 2079
 2080
 2081
 2082
 2083
 2084
 2085
 2086
 2087
 2088
 2089
 2090
 2091
 2092
 2093
 2094
 2095
 2096
 2097
 2098
 2099
 2100
 2101
 2102
 2103
 2104
 2105
 2106
 2107
 2108
 2109
 2110
 2111
 2112
 2113
 2114
 2115
 2116
 2117
 2118
 2119
 2120
 2121
 2122
 2123
 2124
 2125
 2126
 2127
 2128
 2129
 2130
 2131
 2132
 2133
 2134
 2135
 2136
 2137
 2138
 2139
 2140
 2141
 2142
 2143
 2144
 2145
 2146
 2147
 2148
 2149
 2150
 2151
 2152
 2153
 2154
 2155
 2156
 2157
 2158
 2159
 2160
 2161
 2162
 2163
 2164
 2165
 2166
 2167
 2168
 2169
 2170
 2171
 2172
 2173
 2174
 2175
 2176
 2177
 2178
 2179
 2180
 2181
 2182
 2183
 2184
 2185
 2186
 2187
 2188
 2189
 2190
 2191
 2192
 2193
 2194
 2195
 2196
 2197
 2198
 2199
 2200
 2201
 2202
 2203
 2204
 2205
 2206
 2207
 2208
 2209
 2210
 2211
 2212
 2213
 2214
 2215
 2216
 2217
 2218
 2219
 2220
 2221
 2222
 2223
 2224
 2225
 2226
 2227
 2228
 2229
 2230
 2231
 2232
 2233
 2234
 2235
 2236
 2237
 2238
 2239
 2240
 2241
 2242
 2243
 2244
 2245
 2246
 2247
 2248
 2249
 2250
 2251
 2252
 2253
 2254
 2255
 2256
 2257
 2258
 2259
 2260
 2261
 2262
 2263
 2264
 2265
 2266
 2267
 2268
 2269
 2270
 2271
 2272
 2273
 2274
 2275
 2276
 2277
 2278
 2279
 2280
 2281
 2282
 2283
 2284
 2285
 2286
 2287
 2288
 2289
 2290
 2291
 2292
 2293
 2294
 2295
 2296
 2297
 2298
 2299
 2300
 2301
 2302
 2303
 2304
 2305
 2306
 2307
 2308
 2309
 2310
 2311
 2312
 2313
 2314
 2315
 2316
 2317
 2318
 2319
 2320
 2321
 2322
 2323
 2324
 2325
 2326
 2327
 2328
 2329
 2330
 2331
 2332
 2333
 2334
 2335
 2336
 2337
 2338
 2339
 2340
 2341
 2342
 2343
 2344
 2345
 2346
 2347
 2348
 2349
 2350
 2351
 2352
 2353
 2354
 2355
 2356
 2357
 2358
 2359
 2360
 2361
 2362
 2363
 2364
 2365
 2366
 2367
 2368
 2369
 2370
 2371
 2372
 2373
 2374
 2375
 2376
 2377
 2378
 2379
 2380
 2381
 2382
 2383
 2384
 2385
 2386
 2387
 2388
 2389
 2390
 2391
 2392
 2393
 2394
 2395
 2396
 2397
 2398
 2399
 2400
 2401
 2402
 2403
 2404
 2405
 2406
 2407
 2408
 2409
 2410
 2411
 2412
 2413
 2414
 2415
 2416
 2417
 2418
 2419
 2420
 2421
 2422
 2423
 2424
 2425
 2426
 2427
 2428
 2429
 2430
 2431
 2432
 2433
 2434
 2435
 2436
 2437
 2438
 2439
 2440
 2441
 2442
 2443
 2444
 2445
 2446
 2447
 2448
 2449
 2450
 2451
 2452
 2453
 2454
 2455
 2456
 2457
 2458
 2459
 2460
 2461
 2462
 2463
 2464
 2465
 2466
 2467
 2468
 2469
 2470
 2471
 2472
 2473
 2474
 2475
 2476
 2477
 2478
 2479
 2480
 2481
 2482
 2483
 2484
 2485
 2486
 2487
 2488
 2489
 2490
 2491
 2492
 2493
 2494
 2495
 2496
 2497
 2498
 2499
 2500
 2501
 2502
 2503
 2504
 2505
 2506
 2507
 2508
 2509
 2510
 2511
 2512
 2513
 2514
 2515
 2516
 2517
 2518
 2519
 2520
 2521
 2522
 2523
 2524
 2525
 2526
 2527
 2528
 2529
 2530
 2531
 2532
 2533
 2534
 2535
 2536
 2537
 2538
 2539
 2540
 2541
 2542
 2543
 2544
 2545
 2546
 2547
 2548
 2549
 2550
 2551
 2552
 2553
 2554
 2555
 2556
 2557
 2558
 2559
 2560
 2561
 2562
 2563
 2564
 2565
 2566
 2567
 2568
 2569
 2570
 2571
 2572
 2573
 2574
 2575
 2576
 2577
 2578
 2579
 2580
 2581
 2582
 2583
 2584
 2585
 2586
 2587
 2588
 2589
 2590
 2591
 2592
 2593
 2594
 2595
 2596
 2597
 2598
 2599
 2600
 2601
 2602
 2603
 2604
 2605
 2606
 2607
 2608
 2609
 2610
 2611
 2612
 2613
 2614
 2615
 2616
 2617
 2618
 2619
 2620
 2621
 2622
 2623
 2624
 2625
 2626
 2627
 2628
 2629
 2630
 2631
 2632
 2633
 2634
 2635
 2636
 2637
 2638
 2639
 2640
 2641
 2642
 2643
 2644
 2645
 2646
 2647
 2648
 2649
 2650
 2651
 2652
 2653
 2654
 2655
 2656
 2657
 2658
 2659
 2660
 2661
 2662
 2663
 2664
 2665
 2666
 2667
 2668
 2669
 2670
 2671
 2672
 2673
 2674
 2675
 2676
 2677
 2678
 2679
 2680
 2681
 2682
 2683
 2684
 2685
 2686
 2687
 2688
 2689
 2690
 2691
 2692
 2693
 2694
 2695
 2696
 2697
 2698
 2699
 2700
 2701
 2702
 2703
 2704
 2705
 2706
 2707
 2708
 2709
 2710
 2711
 2712
 2713
 2714
 2715
 2716
 2717
 2718
 2719
 2720
 2721
 2722
 2723
 2724
 2725
 2726
 2727
 2728
 2729
 2730
 2731
 2732
 2733
 2734
 2735
 2736
 2737
 2738
 2739
 2740
 2741
 2742
 2743
 2744
 2745
 2746
 2747
 2748
 2749
 2750
 2751
 2752
 2753
 2754
 2755
 2756
 2757
 2758
 2759
 2760
 2761
 2762
 2763
 2764
 2765
 2766
 2767
 2768
 2769
 2770
 2771
 2772
 2773
 2774
 2775
 2776
 2777
 2778
 2779
 2780
 2781
 2782
 2783
 2784
 2785
 2786
 2787
 2788
 2789
 2790
 2791
 2792
 2793
 2794
 2795
 2796
 2797
 2798
 2799
 2800
 2801
 2802
 2803
 2804
 2805
 2806
 2807
 2808
 2809
 2810
 2811
 2812
 2813
 2814
 2815
 2816
 2817
 2818
 2819
 2820
 2821
 2822
 2823
 2824
 2825
 2826
 2827
 2828
 2829
 2830
 2831
 2832
 2833
 2834
 2835
 2836
 2837
 2838
 2839
 2840
 2841
 2842
 2843
 2844
 2845
 2846
 2847
 2848
 2849
 2850
 2851
 2852
 2853
 2854
 2855
 2856
 2857
 2858
 2859
 2860
 2861
 2862
 2863
 2864
 2865
 2866
 2867
 2868
 2869
 2870
 2871
 2872
 2873
 2874
 2875
 2876
 2877
 2878
 2879
 2880
 2881
 2882
 2883
 2884
 2885
 2886
 2887
 2888
 2889
 2890
 2891
 2892
 2893
 2894
 2895
 2896
 2897
 2898
 2899
 2900
 2901
 2902
 2903
 2904
 2905
 2906
 2907
 2908
 2909
 2910
 2911
 2912
 2913
 2914
 2915
 2916
 2917
 2918
 2919
 2920
 2921
 2922
 2923
 2924
 2925
 2926
 2927
 2928
 2929
 2930
 2931
 2932
 2933
 2934
 2935
 2936
 2937
 2938
 2939
 2940
 2941
 2942
 2943
 2944
 2945
 2946
 2947
 2948
 2949
 2950
 2951
 2952
 2953
 2954
 2955
 2956
 2957
 2958
 2959
 2960
 2961
 2962
 2963
 2964
 2965
 2966
 2967
 2968
 2969
 2970
 2971
 2972
 2973
 2974
 2975
 2976
 2977
 2978
 2979
 2980
 2981
 2982
 2983
 2984
 2985
 2986
 2987
 2988
 2989
 2990
 2991
 2992
 2993
 2994
 2995
 2996
 2997
 2998
 2999
 3000
 3001
 3002
 3003
 3004
 3005
 3006
 3007
 3008
 3009
 3010
 3011
 3012
 3013
 3014
 3015
 3016
 3017
 3018
 3019
 3020
 3021
 3022
 3023
 3024
 3025
 3026
 3027
 3028
 3029
 3030
 3031
 3032
 3033
 3034
 3035
 3036
 3037
 3038
 3039
 3040
 3041
 3042
 3043
 3044
 3045
 3046
 3047
 3048
 3049
 3050
 3051
 3052
 3053
 3054
 3055
 3056
 3057
 3058
 3059
 3060
 3061
 3062
 3063
 3064
 3065
 3066
 3067
 3068
 3069
 3070
 3071
 3072
 3073
 3074
 3075
 3076
 3077
 3078
 3079
 3080
 3081
 3082
 3083
 3084
 3085
 3086
 3087
 3088
 3089
 3090
 3091
 3092
 3093
 3094
 3095
 3096
 3097
 3098
 3099
 3100
 3101
 3102
 3103
 3104
 3105
 3106
 3107
 3108
 3109
 3110
 3111
 3112
 3113
 3114
 3115
 3116
 3117
 3118
 3119
 3120
 3121
 3122
 3123
 3124
 3125
 3126
 3127
 3128
 3129
 3130
 3131
 3132
 3133
 3134
 3135
 3136
 3137
 3138
 3139
 3140
 3141
 3142
 3143
 3144
 3145
 3146
 3147
//===- ASTContext.h - Context to hold long-lived AST nodes ------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
/// \file
/// Defines the clang::ASTContext interface.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_AST_ASTCONTEXT_H
#define LLVM_CLANG_AST_ASTCONTEXT_H

#include "clang/AST/ASTContextAllocate.h"
#include "clang/AST/ASTTypeTraits.h"
#include "clang/AST/CanonicalType.h"
#include "clang/AST/CommentCommandTraits.h"
#include "clang/AST/ComparisonCategories.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclBase.h"
#include "clang/AST/DeclarationName.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExternalASTSource.h"
#include "clang/AST/NestedNameSpecifier.h"
#include "clang/AST/PrettyPrinter.h"
#include "clang/AST/RawCommentList.h"
#include "clang/AST/TemplateBase.h"
#include "clang/AST/TemplateName.h"
#include "clang/AST/Type.h"
#include "clang/Basic/AddressSpaces.h"
#include "clang/Basic/AttrKinds.h"
#include "clang/Basic/IdentifierTable.h"
#include "clang/Basic/LLVM.h"
#include "clang/Basic/LangOptions.h"
#include "clang/Basic/Linkage.h"
#include "clang/Basic/OperatorKinds.h"
#include "clang/Basic/PartialDiagnostic.h"
#include "clang/Basic/SanitizerBlacklist.h"
#include "clang/Basic/SourceLocation.h"
#include "clang/Basic/Specifiers.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Basic/XRayLists.h"
#include "llvm/ADT/APSInt.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/IntrusiveRefCntPtr.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/None.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/ADT/PointerUnion.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/TinyPtrVector.h"
#include "llvm/ADT/Triple.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/Support/AlignOf.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/Compiler.h"
#include <cassert>
#include <cstddef>
#include <cstdint>
#include <iterator>
#include <memory>
#include <string>
#include <type_traits>
#include <utility>
#include <vector>

namespace llvm {

struct fltSemantics;

} // namespace llvm

namespace clang {

class APFixedPoint;
class APValue;
class ASTMutationListener;
class ASTRecordLayout;
class AtomicExpr;
class BlockExpr;
class BuiltinTemplateDecl;
class CharUnits;
class CXXABI;
class CXXConstructorDecl;
class CXXMethodDecl;
class CXXRecordDecl;
class DiagnosticsEngine;
class Expr;
class FixedPointSemantics;
class MangleContext;
class MangleNumberingContext;
class MaterializeTemporaryExpr;
class MemberSpecializationInfo;
class Module;
class ObjCCategoryDecl;
class ObjCCategoryImplDecl;
class ObjCContainerDecl;
class ObjCImplDecl;
class ObjCImplementationDecl;
class ObjCInterfaceDecl;
class ObjCIvarDecl;
class ObjCMethodDecl;
class ObjCPropertyDecl;
class ObjCPropertyImplDecl;
class ObjCProtocolDecl;
class ObjCTypeParamDecl;
class Preprocessor;
class Stmt;
class StoredDeclsMap;
class TemplateDecl;
class TemplateParameterList;
class TemplateTemplateParmDecl;
class TemplateTypeParmDecl;
class UnresolvedSetIterator;
class UsingShadowDecl;
class VarTemplateDecl;
class VTableContextBase;

namespace Builtin {

class Context;

} // namespace Builtin

enum BuiltinTemplateKind : int;

namespace comments {

class FullComment;

} // namespace comments

namespace interp {

class Context;

} // namespace interp

struct TypeInfo {
  uint64_t Width = 0;
  unsigned Align = 0;
  bool AlignIsRequired : 1;

  TypeInfo() : AlignIsRequired(false) {}
  TypeInfo(uint64_t Width, unsigned Align, bool AlignIsRequired)
      : Width(Width), Align(Align), AlignIsRequired(AlignIsRequired) {}
};

/// Holds long-lived AST nodes (such as types and decls) that can be
/// referred to throughout the semantic analysis of a file.
class ASTContext : public RefCountedBase<ASTContext> {
public:
  /// Copy initialization expr of a __block variable and a boolean flag that
  /// indicates whether the expression can throw.
  struct BlockVarCopyInit {
    BlockVarCopyInit() = default;
    BlockVarCopyInit(Expr *CopyExpr, bool CanThrow)
        : ExprAndFlag(CopyExpr, CanThrow) {}
    void setExprAndFlag(Expr *CopyExpr, bool CanThrow) {
      ExprAndFlag.setPointerAndInt(CopyExpr, CanThrow);
    }
    Expr *getCopyExpr() const { return ExprAndFlag.getPointer(); }
    bool canThrow() const { return ExprAndFlag.getInt(); }
    llvm::PointerIntPair<Expr *, 1, bool> ExprAndFlag;
  };

private:
  friend class NestedNameSpecifier;

  mutable SmallVector<Type *, 0> Types;
  mutable llvm::FoldingSet<ExtQuals> ExtQualNodes;
  mutable llvm::FoldingSet<ComplexType> ComplexTypes;
  mutable llvm::FoldingSet<PointerType> PointerTypes;
  mutable llvm::FoldingSet<AdjustedType> AdjustedTypes;
  mutable llvm::FoldingSet<BlockPointerType> BlockPointerTypes;
  mutable llvm::FoldingSet<LValueReferenceType> LValueReferenceTypes;
  mutable llvm::FoldingSet<RValueReferenceType> RValueReferenceTypes;
  mutable llvm::FoldingSet<MemberPointerType> MemberPointerTypes;
  mutable llvm::FoldingSet<ConstantArrayType> ConstantArrayTypes;
  mutable llvm::FoldingSet<IncompleteArrayType> IncompleteArrayTypes;
  mutable std::vector<VariableArrayType*> VariableArrayTypes;
  mutable llvm::FoldingSet<DependentSizedArrayType> DependentSizedArrayTypes;
  mutable llvm::FoldingSet<DependentSizedExtVectorType>
    DependentSizedExtVectorTypes;
  mutable llvm::FoldingSet<DependentAddressSpaceType>
      DependentAddressSpaceTypes;
  mutable llvm::FoldingSet<VectorType> VectorTypes;
  mutable llvm::FoldingSet<DependentVectorType> DependentVectorTypes;
  mutable llvm::FoldingSet<FunctionNoProtoType> FunctionNoProtoTypes;
  mutable llvm::ContextualFoldingSet<FunctionProtoType, ASTContext&>
    FunctionProtoTypes;
  mutable llvm::FoldingSet<DependentTypeOfExprType> DependentTypeOfExprTypes;
  mutable llvm::FoldingSet<DependentDecltypeType> DependentDecltypeTypes;
  mutable llvm::FoldingSet<TemplateTypeParmType> TemplateTypeParmTypes;
  mutable llvm::FoldingSet<ObjCTypeParamType> ObjCTypeParamTypes;
  mutable llvm::FoldingSet<SubstTemplateTypeParmType>
    SubstTemplateTypeParmTypes;
  mutable llvm::FoldingSet<SubstTemplateTypeParmPackType>
    SubstTemplateTypeParmPackTypes;
  mutable llvm::ContextualFoldingSet<TemplateSpecializationType, ASTContext&>
    TemplateSpecializationTypes;
  mutable llvm::FoldingSet<ParenType> ParenTypes;
  mutable llvm::FoldingSet<ElaboratedType> ElaboratedTypes;
  mutable llvm::FoldingSet<DependentNameType> DependentNameTypes;
  mutable llvm::ContextualFoldingSet<DependentTemplateSpecializationType,
                                     ASTContext&>
    DependentTemplateSpecializationTypes;
  llvm::FoldingSet<PackExpansionType> PackExpansionTypes;
  mutable llvm::FoldingSet<ObjCObjectTypeImpl> ObjCObjectTypes;
  mutable llvm::FoldingSet<ObjCObjectPointerType> ObjCObjectPointerTypes;
  mutable llvm::FoldingSet<DependentUnaryTransformType>
    DependentUnaryTransformTypes;
  mutable llvm::FoldingSet<AutoType> AutoTypes;
  mutable llvm::FoldingSet<DeducedTemplateSpecializationType>
    DeducedTemplateSpecializationTypes;
  mutable llvm::FoldingSet<AtomicType> AtomicTypes;
  llvm::FoldingSet<AttributedType> AttributedTypes;
  mutable llvm::FoldingSet<PipeType> PipeTypes;

  mutable llvm::FoldingSet<QualifiedTemplateName> QualifiedTemplateNames;
  mutable llvm::FoldingSet<DependentTemplateName> DependentTemplateNames;
  mutable llvm::FoldingSet<SubstTemplateTemplateParmStorage>
    SubstTemplateTemplateParms;
  mutable llvm::ContextualFoldingSet<SubstTemplateTemplateParmPackStorage,
                                     ASTContext&>
    SubstTemplateTemplateParmPacks;

  /// The set of nested name specifiers.
  ///
  /// This set is managed by the NestedNameSpecifier class.
  mutable llvm::FoldingSet<NestedNameSpecifier> NestedNameSpecifiers;
  mutable NestedNameSpecifier *GlobalNestedNameSpecifier = nullptr;

  /// A cache mapping from RecordDecls to ASTRecordLayouts.
  ///
  /// This is lazily created.  This is intentionally not serialized.
  mutable llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>
    ASTRecordLayouts;
  mutable llvm::DenseMap<const ObjCContainerDecl*, const ASTRecordLayout*>
    ObjCLayouts;

  /// A cache from types to size and alignment information.
  using TypeInfoMap = llvm::DenseMap<const Type *, struct TypeInfo>;
  mutable TypeInfoMap MemoizedTypeInfo;

  /// A cache from types to unadjusted alignment information. Only ARM and
  /// AArch64 targets need this information, keeping it separate prevents
  /// imposing overhead on TypeInfo size.
  using UnadjustedAlignMap = llvm::DenseMap<const Type *, unsigned>;
  mutable UnadjustedAlignMap MemoizedUnadjustedAlign;

  /// A cache mapping from CXXRecordDecls to key functions.
  llvm::DenseMap<const CXXRecordDecl*, LazyDeclPtr> KeyFunctions;

  /// Mapping from ObjCContainers to their ObjCImplementations.
  llvm::DenseMap<ObjCContainerDecl*, ObjCImplDecl*> ObjCImpls;

  /// Mapping from ObjCMethod to its duplicate declaration in the same
  /// interface.
  llvm::DenseMap<const ObjCMethodDecl*,const ObjCMethodDecl*> ObjCMethodRedecls;

  /// Mapping from __block VarDecls to BlockVarCopyInit.
  llvm::DenseMap<const VarDecl *, BlockVarCopyInit> BlockVarCopyInits;

  /// Mapping from materialized temporaries with static storage duration
  /// that appear in constant initializers to their evaluated values.  These are
  /// allocated in a std::map because their address must be stable.
  llvm::DenseMap<const MaterializeTemporaryExpr *, APValue *>
    MaterializedTemporaryValues;

  /// Used to cleanups APValues stored in the AST.
  mutable llvm::SmallVector<APValue *, 0> APValueCleanups;

  /// A cache mapping a string value to a StringLiteral object with the same
  /// value.
  ///
  /// This is lazily created.  This is intentionally not serialized.
  mutable llvm::StringMap<StringLiteral *> StringLiteralCache;

  /// Representation of a "canonical" template template parameter that
  /// is used in canonical template names.
  class CanonicalTemplateTemplateParm : public llvm::FoldingSetNode {
    TemplateTemplateParmDecl *Parm;

  public:
    CanonicalTemplateTemplateParm(TemplateTemplateParmDecl *Parm)
        : Parm(Parm) {}

    TemplateTemplateParmDecl *getParam() const { return Parm; }

    void Profile(llvm::FoldingSetNodeID &ID) { Profile(ID, Parm); }

    static void Profile(llvm::FoldingSetNodeID &ID,
                        TemplateTemplateParmDecl *Parm);
  };
  mutable llvm::FoldingSet<CanonicalTemplateTemplateParm>
    CanonTemplateTemplateParms;

  TemplateTemplateParmDecl *
    getCanonicalTemplateTemplateParmDecl(TemplateTemplateParmDecl *TTP) const;

  /// The typedef for the __int128_t type.
  mutable TypedefDecl *Int128Decl = nullptr;

  /// The typedef for the __uint128_t type.
  mutable TypedefDecl *UInt128Decl = nullptr;

  /// The typedef for the target specific predefined
  /// __builtin_va_list type.
  mutable TypedefDecl *BuiltinVaListDecl = nullptr;

  /// The typedef for the predefined \c __builtin_ms_va_list type.
  mutable TypedefDecl *BuiltinMSVaListDecl = nullptr;

  /// The typedef for the predefined \c id type.
  mutable TypedefDecl *ObjCIdDecl = nullptr;

  /// The typedef for the predefined \c SEL type.
  mutable TypedefDecl *ObjCSelDecl = nullptr;

  /// The typedef for the predefined \c Class type.
  mutable TypedefDecl *ObjCClassDecl = nullptr;

  /// The typedef for the predefined \c Protocol class in Objective-C.
  mutable ObjCInterfaceDecl *ObjCProtocolClassDecl = nullptr;

  /// The typedef for the predefined 'BOOL' type.
  mutable TypedefDecl *BOOLDecl = nullptr;

  // Typedefs which may be provided defining the structure of Objective-C
  // pseudo-builtins
  QualType ObjCIdRedefinitionType;
  QualType ObjCClassRedefinitionType;
  QualType ObjCSelRedefinitionType;

  /// The identifier 'bool'.
  mutable IdentifierInfo *BoolName = nullptr;

  /// The identifier 'NSObject'.
  mutable IdentifierInfo *NSObjectName = nullptr;

  /// The identifier 'NSCopying'.
  IdentifierInfo *NSCopyingName = nullptr;

  /// The identifier '__make_integer_seq'.
  mutable IdentifierInfo *MakeIntegerSeqName = nullptr;

  /// The identifier '__type_pack_element'.
  mutable IdentifierInfo *TypePackElementName = nullptr;

  QualType ObjCConstantStringType;
  mutable RecordDecl *CFConstantStringTagDecl = nullptr;
  mutable TypedefDecl *CFConstantStringTypeDecl = nullptr;

  mutable QualType ObjCSuperType;

  QualType ObjCNSStringType;

  /// The typedef declaration for the Objective-C "instancetype" type.
  TypedefDecl *ObjCInstanceTypeDecl = nullptr;

  /// The type for the C FILE type.
  TypeDecl *FILEDecl = nullptr;

  /// The type for the C jmp_buf type.
  TypeDecl *jmp_bufDecl = nullptr;

  /// The type for the C sigjmp_buf type.
  TypeDecl *sigjmp_bufDecl = nullptr;

  /// The type for the C ucontext_t type.
  TypeDecl *ucontext_tDecl = nullptr;

  /// Type for the Block descriptor for Blocks CodeGen.
  ///
  /// Since this is only used for generation of debug info, it is not
  /// serialized.
  mutable RecordDecl *BlockDescriptorType = nullptr;

  /// Type for the Block descriptor for Blocks CodeGen.
  ///
  /// Since this is only used for generation of debug info, it is not
  /// serialized.
  mutable RecordDecl *BlockDescriptorExtendedType = nullptr;

  /// Declaration for the CUDA cudaConfigureCall function.
  FunctionDecl *cudaConfigureCallDecl = nullptr;

  /// Keeps track of all declaration attributes.
  ///
  /// Since so few decls have attrs, we keep them in a hash map instead of
  /// wasting space in the Decl class.
  llvm::DenseMap<const Decl*, AttrVec*> DeclAttrs;

  /// A mapping from non-redeclarable declarations in modules that were
  /// merged with other declarations to the canonical declaration that they were
  /// merged into.
  llvm::DenseMap<Decl*, Decl*> MergedDecls;

  /// A mapping from a defining declaration to a list of modules (other
  /// than the owning module of the declaration) that contain merged
  /// definitions of that entity.
  llvm::DenseMap<NamedDecl*, llvm::TinyPtrVector<Module*>> MergedDefModules;

  /// Initializers for a module, in order. Each Decl will be either
  /// something that has a semantic effect on startup (such as a variable with
  /// a non-constant initializer), or an ImportDecl (which recursively triggers
  /// initialization of another module).
  struct PerModuleInitializers {
    llvm::SmallVector<Decl*, 4> Initializers;
    llvm::SmallVector<uint32_t, 4> LazyInitializers;

    void resolve(ASTContext &Ctx);
  };
  llvm::DenseMap<Module*, PerModuleInitializers*> ModuleInitializers;

  ASTContext &this_() { return *this; }

public:
  /// A type synonym for the TemplateOrInstantiation mapping.
  using TemplateOrSpecializationInfo =
      llvm::PointerUnion<VarTemplateDecl *, MemberSpecializationInfo *>;

private:
  friend class ASTDeclReader;
  friend class ASTReader;
  friend class ASTWriter;
  friend class CXXRecordDecl;

  /// A mapping to contain the template or declaration that
  /// a variable declaration describes or was instantiated from,
  /// respectively.
  ///
  /// For non-templates, this value will be NULL. For variable
  /// declarations that describe a variable template, this will be a
  /// pointer to a VarTemplateDecl. For static data members
  /// of class template specializations, this will be the
  /// MemberSpecializationInfo referring to the member variable that was
  /// instantiated or specialized. Thus, the mapping will keep track of
  /// the static data member templates from which static data members of
  /// class template specializations were instantiated.
  ///
  /// Given the following example:
  ///
  /// \code
  /// template<typename T>
  /// struct X {
  ///   static T value;
  /// };
  ///
  /// template<typename T>
  ///   T X<T>::value = T(17);
  ///
  /// int *x = &X<int>::value;
  /// \endcode
  ///
  /// This mapping will contain an entry that maps from the VarDecl for
  /// X<int>::value to the corresponding VarDecl for X<T>::value (within the
  /// class template X) and will be marked TSK_ImplicitInstantiation.
  llvm::DenseMap<const VarDecl *, TemplateOrSpecializationInfo>
  TemplateOrInstantiation;

  /// Keeps track of the declaration from which a using declaration was
  /// created during instantiation.
  ///
  /// The source and target declarations are always a UsingDecl, an
  /// UnresolvedUsingValueDecl, or an UnresolvedUsingTypenameDecl.
  ///
  /// For example:
  /// \code
  /// template<typename T>
  /// struct A {
  ///   void f();
  /// };
  ///
  /// template<typename T>
  /// struct B : A<T> {
  ///   using A<T>::f;
  /// };
  ///
  /// template struct B<int>;
  /// \endcode
  ///
  /// This mapping will contain an entry that maps from the UsingDecl in
  /// B<int> to the UnresolvedUsingDecl in B<T>.
  llvm::DenseMap<NamedDecl *, NamedDecl *> InstantiatedFromUsingDecl;

  llvm::DenseMap<UsingShadowDecl*, UsingShadowDecl*>
    InstantiatedFromUsingShadowDecl;

  llvm::DenseMap<FieldDecl *, FieldDecl *> InstantiatedFromUnnamedFieldDecl;

  /// Mapping that stores the methods overridden by a given C++
  /// member function.
  ///
  /// Since most C++ member functions aren't virtual and therefore
  /// don't override anything, we store the overridden functions in
  /// this map on the side rather than within the CXXMethodDecl structure.
  using CXXMethodVector = llvm::TinyPtrVector<const CXXMethodDecl *>;
  llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector> OverriddenMethods;

  /// Mapping from each declaration context to its corresponding
  /// mangling numbering context (used for constructs like lambdas which
  /// need to be consistently numbered for the mangler).
  llvm::DenseMap<const DeclContext *, std::unique_ptr<MangleNumberingContext>>
      MangleNumberingContexts;

  /// Side-table of mangling numbers for declarations which rarely
  /// need them (like static local vars).
  llvm::MapVector<const NamedDecl *, unsigned> MangleNumbers;
  llvm::MapVector<const VarDecl *, unsigned> StaticLocalNumbers;

  /// Mapping that stores parameterIndex values for ParmVarDecls when
  /// that value exceeds the bitfield size of ParmVarDeclBits.ParameterIndex.
  using ParameterIndexTable = llvm::DenseMap<const VarDecl *, unsigned>;
  ParameterIndexTable ParamIndices;

  ImportDecl *FirstLocalImport = nullptr;
  ImportDecl *LastLocalImport = nullptr;

  TranslationUnitDecl *TUDecl;
  mutable ExternCContextDecl *ExternCContext = nullptr;
  mutable BuiltinTemplateDecl *MakeIntegerSeqDecl = nullptr;
  mutable BuiltinTemplateDecl *TypePackElementDecl = nullptr;

  /// The associated SourceManager object.
  SourceManager &SourceMgr;

  /// The language options used to create the AST associated with
  ///  this ASTContext object.
  LangOptions &LangOpts;

  /// Blacklist object that is used by sanitizers to decide which
  /// entities should not be instrumented.
  std::unique_ptr<SanitizerBlacklist> SanitizerBL;

  /// Function filtering mechanism to determine whether a given function
  /// should be imbued with the XRay "always" or "never" attributes.
  std::unique_ptr<XRayFunctionFilter> XRayFilter;

  /// The allocator used to create AST objects.
  ///
  /// AST objects are never destructed; rather, all memory associated with the
  /// AST objects will be released when the ASTContext itself is destroyed.
  mutable llvm::BumpPtrAllocator BumpAlloc;

  /// Allocator for partial diagnostics.
  PartialDiagnostic::StorageAllocator DiagAllocator;

  /// The current C++ ABI.
  std::unique_ptr<CXXABI> ABI;
  CXXABI *createCXXABI(const TargetInfo &T);

  /// The logical -> physical address space map.
  const LangASMap *AddrSpaceMap = nullptr;

  /// Address space map mangling must be used with language specific
  /// address spaces (e.g. OpenCL/CUDA)
  bool AddrSpaceMapMangling;

  const TargetInfo *Target = nullptr;
  const TargetInfo *AuxTarget = nullptr;
  clang::PrintingPolicy PrintingPolicy;
  std::unique_ptr<interp::Context> InterpContext;

public:
  IdentifierTable &Idents;
  SelectorTable &Selectors;
  Builtin::Context &BuiltinInfo;
  mutable DeclarationNameTable DeclarationNames;
  IntrusiveRefCntPtr<ExternalASTSource> ExternalSource;
  ASTMutationListener *Listener = nullptr;

  /// Returns the clang bytecode interpreter context.
  interp::Context &getInterpContext();

  /// Container for either a single DynTypedNode or for an ArrayRef to
  /// DynTypedNode. For use with ParentMap.
  class DynTypedNodeList {
    using DynTypedNode = ast_type_traits::DynTypedNode;

    llvm::AlignedCharArrayUnion<ast_type_traits::DynTypedNode,
                                ArrayRef<DynTypedNode>> Storage;
    bool IsSingleNode;

  public:
    DynTypedNodeList(const DynTypedNode &N) : IsSingleNode(true) {
      new (Storage.buffer) DynTypedNode(N);
    }

    DynTypedNodeList(ArrayRef<DynTypedNode> A) : IsSingleNode(false) {
      new (Storage.buffer) ArrayRef<DynTypedNode>(A);
    }

    const ast_type_traits::DynTypedNode *begin() const {
      if (!IsSingleNode)
        return reinterpret_cast<const ArrayRef<DynTypedNode> *>(Storage.buffer)
            ->begin();
      return reinterpret_cast<const DynTypedNode *>(Storage.buffer);
    }

    const ast_type_traits::DynTypedNode *end() const {
      if (!IsSingleNode)
        return reinterpret_cast<const ArrayRef<DynTypedNode> *>(Storage.buffer)
            ->end();
      return reinterpret_cast<const DynTypedNode *>(Storage.buffer) + 1;
    }

    size_t size() const { return end() - begin(); }
    bool empty() const { return begin() == end(); }

    const DynTypedNode &operator[](size_t N) const {
      assert(N < size() && "Out of bounds!");
      return *(begin() + N);
    }
  };

  // A traversal scope limits the parts of the AST visible to certain analyses.
  // RecursiveASTVisitor::TraverseAST will only visit reachable nodes, and
  // getParents() will only observe reachable parent edges.
  //
  // The scope is defined by a set of "top-level" declarations.
  // Initially, it is the entire TU: {getTranslationUnitDecl()}.
  // Changing the scope clears the parent cache, which is expensive to rebuild.
  std::vector<Decl *> getTraversalScope() const { return TraversalScope; }
  void setTraversalScope(const std::vector<Decl *> &);

  /// Returns the parents of the given node (within the traversal scope).
  ///
  /// Note that this will lazily compute the parents of all nodes
  /// and store them for later retrieval. Thus, the first call is O(n)
  /// in the number of AST nodes.
  ///
  /// Caveats and FIXMEs:
  /// Calculating the parent map over all AST nodes will need to load the
  /// full AST. This can be undesirable in the case where the full AST is
  /// expensive to create (for example, when using precompiled header
  /// preambles). Thus, there are good opportunities for optimization here.
  /// One idea is to walk the given node downwards, looking for references
  /// to declaration contexts - once a declaration context is found, compute
  /// the parent map for the declaration context; if that can satisfy the
  /// request, loading the whole AST can be avoided. Note that this is made
  /// more complex by statements in templates having multiple parents - those
  /// problems can be solved by building closure over the templated parts of
  /// the AST, which also avoids touching large parts of the AST.
  /// Additionally, we will want to add an interface to already give a hint
  /// where to search for the parents, for example when looking at a statement
  /// inside a certain function.
  ///
  /// 'NodeT' can be one of Decl, Stmt, Type, TypeLoc,
  /// NestedNameSpecifier or NestedNameSpecifierLoc.
  template <typename NodeT> DynTypedNodeList getParents(const NodeT &Node) {
    return getParents(ast_type_traits::DynTypedNode::create(Node));
  }

  DynTypedNodeList getParents(const ast_type_traits::DynTypedNode &Node);

  const clang::PrintingPolicy &getPrintingPolicy() const {
    return PrintingPolicy;
  }

  void setPrintingPolicy(const clang::PrintingPolicy &Policy) {
    PrintingPolicy = Policy;
  }

  SourceManager& getSourceManager() { return SourceMgr; }
  const SourceManager& getSourceManager() const { return SourceMgr; }

  llvm::BumpPtrAllocator &getAllocator() const {
    return BumpAlloc;
  }

  void *Allocate(size_t Size, unsigned Align = 8) const {
    return BumpAlloc.Allocate(Size, Align);
  }
  template <typename T> T *Allocate(size_t Num = 1) const {
    return static_cast<T *>(Allocate(Num * sizeof(T), alignof(T)));
  }
  void Deallocate(void *Ptr) const {}

  /// Return the total amount of physical memory allocated for representing
  /// AST nodes and type information.
  size_t getASTAllocatedMemory() const {
    return BumpAlloc.getTotalMemory();
  }

  /// Return the total memory used for various side tables.
  size_t getSideTableAllocatedMemory() const;

  PartialDiagnostic::StorageAllocator &getDiagAllocator() {
    return DiagAllocator;
  }

  const TargetInfo &getTargetInfo() const { return *Target; }
  const TargetInfo *getAuxTargetInfo() const { return AuxTarget; }

  /// getIntTypeForBitwidth -
  /// sets integer QualTy according to specified details:
  /// bitwidth, signed/unsigned.
  /// Returns empty type if there is no appropriate target types.
  QualType getIntTypeForBitwidth(unsigned DestWidth,
                                 unsigned Signed) const;

  /// getRealTypeForBitwidth -
  /// sets floating point QualTy according to specified bitwidth.
  /// Returns empty type if there is no appropriate target types.
  QualType getRealTypeForBitwidth(unsigned DestWidth) const;

  bool AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const;

  const LangOptions& getLangOpts() const { return LangOpts; }

  const SanitizerBlacklist &getSanitizerBlacklist() const {
    return *SanitizerBL;
  }

  const XRayFunctionFilter &getXRayFilter() const {
    return *XRayFilter;
  }

  DiagnosticsEngine &getDiagnostics() const;

  FullSourceLoc getFullLoc(SourceLocation Loc) const {
    return FullSourceLoc(Loc,SourceMgr);
  }

  /// All comments in this translation unit.
  RawCommentList Comments;

  /// True if comments are already loaded from ExternalASTSource.
  mutable bool CommentsLoaded = false;

  /// Mapping from declaration to directly attached comment.
  ///
  /// Raw comments are owned by Comments list.  This mapping is populated
  /// lazily.
  mutable llvm::DenseMap<const Decl *, const RawComment *> DeclRawComments;

  /// Mapping from canonical declaration to the first redeclaration in chain
  /// that has a comment attached.
  ///
  /// Raw comments are owned by Comments list.  This mapping is populated
  /// lazily.
  mutable llvm::DenseMap<const Decl *, const Decl *> RedeclChainComments;

  /// Keeps track of redeclaration chains that don't have any comment attached.
  /// Mapping from canonical declaration to redeclaration chain that has no
  /// comments attached to any redeclaration. Specifically it's mapping to
  /// the last redeclaration we've checked.
  ///
  /// Shall not contain declarations that have comments attached to any
  /// redeclaration in their chain.
  mutable llvm::DenseMap<const Decl *, const Decl *> CommentlessRedeclChains;

  /// Mapping from declarations to parsed comments attached to any
  /// redeclaration.
  mutable llvm::DenseMap<const Decl *, comments::FullComment *> ParsedComments;

  /// Attaches \p Comment to \p OriginalD and to its redeclaration chain
  /// and removes the redeclaration chain from the set of commentless chains.
  ///
  /// Don't do anything if a comment has already been attached to \p OriginalD
  /// or its redeclaration chain.
  void cacheRawCommentForDecl(const Decl &OriginalD,
                              const RawComment &Comment) const;

  /// \returns searches \p CommentsInFile for doc comment for \p D.
  ///
  /// \p RepresentativeLocForDecl is used as a location for searching doc
  /// comments. \p CommentsInFile is a mapping offset -> comment of files in the
  /// same file where \p RepresentativeLocForDecl is.
  RawComment *getRawCommentForDeclNoCacheImpl(
      const Decl *D, const SourceLocation RepresentativeLocForDecl,
      const std::map<unsigned, RawComment *> &CommentsInFile) const;

  /// Return the documentation comment attached to a given declaration,
  /// without looking into cache.
  RawComment *getRawCommentForDeclNoCache(const Decl *D) const;

public:
  RawCommentList &getRawCommentList() {
    return Comments;
  }

  void addComment(const RawComment &RC) {
    assert(LangOpts.RetainCommentsFromSystemHeaders ||
           !SourceMgr.isInSystemHeader(RC.getSourceRange().getBegin()));
    Comments.addComment(RC, LangOpts.CommentOpts, BumpAlloc);
  }

  /// Return the documentation comment attached to a given declaration.
  /// Returns nullptr if no comment is attached.
  ///
  /// \param OriginalDecl if not nullptr, is set to declaration AST node that
  /// had the comment, if the comment we found comes from a redeclaration.
  const RawComment *
  getRawCommentForAnyRedecl(const Decl *D,
                            const Decl **OriginalDecl = nullptr) const;

  /// Searches existing comments for doc comments that should be attached to \p
  /// Decls. If any doc comment is found, it is parsed.
  ///
  /// Requirement: All \p Decls are in the same file.
  ///
  /// If the last comment in the file is already attached we assume
  /// there are not comments left to be attached to \p Decls.
  void attachCommentsToJustParsedDecls(ArrayRef<Decl *> Decls,
                                       const Preprocessor *PP);

  /// Return parsed documentation comment attached to a given declaration.
  /// Returns nullptr if no comment is attached.
  ///
  /// \param PP the Preprocessor used with this TU.  Could be nullptr if
  /// preprocessor is not available.
  comments::FullComment *getCommentForDecl(const Decl *D,
                                           const Preprocessor *PP) const;

  /// Return parsed documentation comment attached to a given declaration.
  /// Returns nullptr if no comment is attached. Does not look at any
  /// redeclarations of the declaration.
  comments::FullComment *getLocalCommentForDeclUncached(const Decl *D) const;

  comments::FullComment *cloneFullComment(comments::FullComment *FC,
                                         const Decl *D) const;

private:
  mutable comments::CommandTraits CommentCommandTraits;

  /// Iterator that visits import declarations.
  class import_iterator {
    ImportDecl *Import = nullptr;

  public:
    using value_type = ImportDecl *;
    using reference = ImportDecl *;
    using pointer = ImportDecl *;
    using difference_type = int;
    using iterator_category = std::forward_iterator_tag;

    import_iterator() = default;
    explicit import_iterator(ImportDecl *Import) : Import(Import) {}

    reference operator*() const { return Import; }
    pointer operator->() const { return Import; }

    import_iterator &operator++() {
      Import = ASTContext::getNextLocalImport(Import);
      return *this;
    }

    import_iterator operator++(int) {
      import_iterator Other(*this);
      ++(*this);
      return Other;
    }

    friend bool operator==(import_iterator X, import_iterator Y) {
      return X.Import == Y.Import;
    }

    friend bool operator!=(import_iterator X, import_iterator Y) {
      return X.Import != Y.Import;
    }
  };

public:
  comments::CommandTraits &getCommentCommandTraits() const {
    return CommentCommandTraits;
  }

  /// Retrieve the attributes for the given declaration.
  AttrVec& getDeclAttrs(const Decl *D);

  /// Erase the attributes corresponding to the given declaration.
  void eraseDeclAttrs(const Decl *D);

  /// If this variable is an instantiated static data member of a
  /// class template specialization, returns the templated static data member
  /// from which it was instantiated.
  // FIXME: Remove ?
  MemberSpecializationInfo *getInstantiatedFromStaticDataMember(
                                                           const VarDecl *Var);

  TemplateOrSpecializationInfo
  getTemplateOrSpecializationInfo(const VarDecl *Var);

  /// Note that the static data member \p Inst is an instantiation of
  /// the static data member template \p Tmpl of a class template.
  void setInstantiatedFromStaticDataMember(VarDecl *Inst, VarDecl *Tmpl,
                                           TemplateSpecializationKind TSK,
                        SourceLocation PointOfInstantiation = SourceLocation());

  void setTemplateOrSpecializationInfo(VarDecl *Inst,
                                       TemplateOrSpecializationInfo TSI);

  /// If the given using decl \p Inst is an instantiation of a
  /// (possibly unresolved) using decl from a template instantiation,
  /// return it.
  NamedDecl *getInstantiatedFromUsingDecl(NamedDecl *Inst);

  /// Remember that the using decl \p Inst is an instantiation
  /// of the using decl \p Pattern of a class template.
  void setInstantiatedFromUsingDecl(NamedDecl *Inst, NamedDecl *Pattern);

  void setInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst,
                                          UsingShadowDecl *Pattern);
  UsingShadowDecl *getInstantiatedFromUsingShadowDecl(UsingShadowDecl *Inst);

  FieldDecl *getInstantiatedFromUnnamedFieldDecl(FieldDecl *Field);

  void setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst, FieldDecl *Tmpl);

  // Access to the set of methods overridden by the given C++ method.
  using overridden_cxx_method_iterator = CXXMethodVector::const_iterator;
  overridden_cxx_method_iterator
  overridden_methods_begin(const CXXMethodDecl *Method) const;

  overridden_cxx_method_iterator
  overridden_methods_end(const CXXMethodDecl *Method) const;

  unsigned overridden_methods_size(const CXXMethodDecl *Method) const;

  using overridden_method_range =
      llvm::iterator_range<overridden_cxx_method_iterator>;

  overridden_method_range overridden_methods(const CXXMethodDecl *Method) const;

  /// Note that the given C++ \p Method overrides the given \p
  /// Overridden method.
  void addOverriddenMethod(const CXXMethodDecl *Method,
                           const CXXMethodDecl *Overridden);

  /// Return C++ or ObjC overridden methods for the given \p Method.
  ///
  /// An ObjC method is considered to override any method in the class's
  /// base classes, its protocols, or its categories' protocols, that has
  /// the same selector and is of the same kind (class or instance).
  /// A method in an implementation is not considered as overriding the same
  /// method in the interface or its categories.
  void getOverriddenMethods(
                        const NamedDecl *Method,
                        SmallVectorImpl<const NamedDecl *> &Overridden) const;

  /// Notify the AST context that a new import declaration has been
  /// parsed or implicitly created within this translation unit.
  void addedLocalImportDecl(ImportDecl *Import);

  static ImportDecl *getNextLocalImport(ImportDecl *Import) {
    return Import->NextLocalImport;
  }

  using import_range = llvm::iterator_range<import_iterator>;

  import_range local_imports() const {
    return import_range(import_iterator(FirstLocalImport), import_iterator());
  }

  Decl *getPrimaryMergedDecl(Decl *D) {
    Decl *Result = MergedDecls.lookup(D);
    return Result ? Result : D;
  }
  void setPrimaryMergedDecl(Decl *D, Decl *Primary) {
    MergedDecls[D] = Primary;
  }

  /// Note that the definition \p ND has been merged into module \p M,
  /// and should be visible whenever \p M is visible.
  void mergeDefinitionIntoModule(NamedDecl *ND, Module *M,
                                 bool NotifyListeners = true);

  /// Clean up the merged definition list. Call this if you might have
  /// added duplicates into the list.
  void deduplicateMergedDefinitonsFor(NamedDecl *ND);

  /// Get the additional modules in which the definition \p Def has
  /// been merged.
  ArrayRef<Module*> getModulesWithMergedDefinition(const NamedDecl *Def) {
    auto MergedIt =
        MergedDefModules.find(cast<NamedDecl>(Def->getCanonicalDecl()));
    if (MergedIt == MergedDefModules.end())
      return None;
    return MergedIt->second;
  }

  /// Add a declaration to the list of declarations that are initialized
  /// for a module. This will typically be a global variable (with internal
  /// linkage) that runs module initializers, such as the iostream initializer,
  /// or an ImportDecl nominating another module that has initializers.
  void addModuleInitializer(Module *M, Decl *Init);

  void addLazyModuleInitializers(Module *M, ArrayRef<uint32_t> IDs);

  /// Get the initializations to perform when importing a module, if any.
  ArrayRef<Decl*> getModuleInitializers(Module *M);

  TranslationUnitDecl *getTranslationUnitDecl() const { return TUDecl; }

  ExternCContextDecl *getExternCContextDecl() const;
  BuiltinTemplateDecl *getMakeIntegerSeqDecl() const;
  BuiltinTemplateDecl *getTypePackElementDecl() const;

  // Builtin Types.
  CanQualType VoidTy;
  CanQualType BoolTy;
  CanQualType CharTy;
  CanQualType WCharTy;  // [C++ 3.9.1p5].
  CanQualType WideCharTy; // Same as WCharTy in C++, integer type in C99.
  CanQualType WIntTy;   // [C99 7.24.1], integer type unchanged by default promotions.
  CanQualType Char8Ty;  // [C++20 proposal]
  CanQualType Char16Ty; // [C++0x 3.9.1p5], integer type in C99.
  CanQualType Char32Ty; // [C++0x 3.9.1p5], integer type in C99.
  CanQualType SignedCharTy, ShortTy, IntTy, LongTy, LongLongTy, Int128Ty;
  CanQualType UnsignedCharTy, UnsignedShortTy, UnsignedIntTy, UnsignedLongTy;
  CanQualType UnsignedLongLongTy, UnsignedInt128Ty;
  CanQualType FloatTy, DoubleTy, LongDoubleTy, Float128Ty;
  CanQualType ShortAccumTy, AccumTy,
      LongAccumTy;  // ISO/IEC JTC1 SC22 WG14 N1169 Extension
  CanQualType UnsignedShortAccumTy, UnsignedAccumTy, UnsignedLongAccumTy;
  CanQualType ShortFractTy, FractTy, LongFractTy;
  CanQualType UnsignedShortFractTy, UnsignedFractTy, UnsignedLongFractTy;
  CanQualType SatShortAccumTy, SatAccumTy, SatLongAccumTy;
  CanQualType SatUnsignedShortAccumTy, SatUnsignedAccumTy,
      SatUnsignedLongAccumTy;
  CanQualType SatShortFractTy, SatFractTy, SatLongFractTy;
  CanQualType SatUnsignedShortFractTy, SatUnsignedFractTy,
      SatUnsignedLongFractTy;
  CanQualType HalfTy; // [OpenCL 6.1.1.1], ARM NEON
  CanQualType Float16Ty; // C11 extension ISO/IEC TS 18661-3
  CanQualType FloatComplexTy, DoubleComplexTy, LongDoubleComplexTy;
  CanQualType Float128ComplexTy;
  CanQualType VoidPtrTy, NullPtrTy;
  CanQualType DependentTy, OverloadTy, BoundMemberTy, UnknownAnyTy;
  CanQualType BuiltinFnTy;
  CanQualType PseudoObjectTy, ARCUnbridgedCastTy;
  CanQualType ObjCBuiltinIdTy, ObjCBuiltinClassTy, ObjCBuiltinSelTy;
  CanQualType ObjCBuiltinBoolTy;
#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
  CanQualType SingletonId;
#include "clang/Basic/OpenCLImageTypes.def"
  CanQualType OCLSamplerTy, OCLEventTy, OCLClkEventTy;
  CanQualType OCLQueueTy, OCLReserveIDTy;
  CanQualType OMPArraySectionTy;
#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
  CanQualType Id##Ty;
#include "clang/Basic/OpenCLExtensionTypes.def"
#define SVE_TYPE(Name, Id, SingletonId) \
  CanQualType SingletonId;
#include "clang/Basic/AArch64SVEACLETypes.def"

  // Types for deductions in C++0x [stmt.ranged]'s desugaring. Built on demand.
  mutable QualType AutoDeductTy;     // Deduction against 'auto'.
  mutable QualType AutoRRefDeductTy; // Deduction against 'auto &&'.

  // Decl used to help define __builtin_va_list for some targets.
  // The decl is built when constructing 'BuiltinVaListDecl'.
  mutable Decl *VaListTagDecl;

  ASTContext(LangOptions &LOpts, SourceManager &SM, IdentifierTable &idents,
             SelectorTable &sels, Builtin::Context &builtins);
  ASTContext(const ASTContext &) = delete;
  ASTContext &operator=(const ASTContext &) = delete;
  ~ASTContext();

  /// Attach an external AST source to the AST context.
  ///
  /// The external AST source provides the ability to load parts of
  /// the abstract syntax tree as needed from some external storage,
  /// e.g., a precompiled header.
  void setExternalSource(IntrusiveRefCntPtr<ExternalASTSource> Source);

  /// Retrieve a pointer to the external AST source associated
  /// with this AST context, if any.
  ExternalASTSource *getExternalSource() const {
    return ExternalSource.get();
  }

  /// Attach an AST mutation listener to the AST context.
  ///
  /// The AST mutation listener provides the ability to track modifications to
  /// the abstract syntax tree entities committed after they were initially
  /// created.
  void setASTMutationListener(ASTMutationListener *Listener) {
    this->Listener = Listener;
  }

  /// Retrieve a pointer to the AST mutation listener associated
  /// with this AST context, if any.
  ASTMutationListener *getASTMutationListener() const { return Listener; }

  void PrintStats() const;
  const SmallVectorImpl<Type *>& getTypes() const { return Types; }

  BuiltinTemplateDecl *buildBuiltinTemplateDecl(BuiltinTemplateKind BTK,
                                                const IdentifierInfo *II) const;

  /// Create a new implicit TU-level CXXRecordDecl or RecordDecl
  /// declaration.
  RecordDecl *buildImplicitRecord(StringRef Name,
                                  RecordDecl::TagKind TK = TTK_Struct) const;

  /// Create a new implicit TU-level typedef declaration.
  TypedefDecl *buildImplicitTypedef(QualType T, StringRef Name) const;

  /// Retrieve the declaration for the 128-bit signed integer type.
  TypedefDecl *getInt128Decl() const;

  /// Retrieve the declaration for the 128-bit unsigned integer type.
  TypedefDecl *getUInt128Decl() const;

  //===--------------------------------------------------------------------===//
  //                           Type Constructors
  //===--------------------------------------------------------------------===//

private:
  /// Return a type with extended qualifiers.
  QualType getExtQualType(const Type *Base, Qualifiers Quals) const;

  QualType getTypeDeclTypeSlow(const TypeDecl *Decl) const;

  QualType getPipeType(QualType T, bool ReadOnly) const;

public:
  /// Return the uniqued reference to the type for an address space
  /// qualified type with the specified type and address space.
  ///
  /// The resulting type has a union of the qualifiers from T and the address
  /// space. If T already has an address space specifier, it is silently
  /// replaced.
  QualType getAddrSpaceQualType(QualType T, LangAS AddressSpace) const;

  /// Remove any existing address space on the type and returns the type
  /// with qualifiers intact (or that's the idea anyway)
  ///
  /// The return type should be T with all prior qualifiers minus the address
  /// space.
  QualType removeAddrSpaceQualType(QualType T) const;

  /// Apply Objective-C protocol qualifiers to the given type.
  /// \param allowOnPointerType specifies if we can apply protocol
  /// qualifiers on ObjCObjectPointerType. It can be set to true when
  /// constructing the canonical type of a Objective-C type parameter.
  QualType applyObjCProtocolQualifiers(QualType type,
      ArrayRef<ObjCProtocolDecl *> protocols, bool &hasError,
      bool allowOnPointerType = false) const;

  /// Return the uniqued reference to the type for an Objective-C
  /// gc-qualified type.
  ///
  /// The resulting type has a union of the qualifiers from T and the gc
  /// attribute.
  QualType getObjCGCQualType(QualType T, Qualifiers::GC gcAttr) const;

  /// Return the uniqued reference to the type for a \c restrict
  /// qualified type.
  ///
  /// The resulting type has a union of the qualifiers from \p T and
  /// \c restrict.
  QualType getRestrictType(QualType T) const {
    return T.withFastQualifiers(Qualifiers::Restrict);
  }

  /// Return the uniqued reference to the type for a \c volatile
  /// qualified type.
  ///
  /// The resulting type has a union of the qualifiers from \p T and
  /// \c volatile.
  QualType getVolatileType(QualType T) const {
    return T.withFastQualifiers(Qualifiers::Volatile);
  }

  /// Return the uniqued reference to the type for a \c const
  /// qualified type.
  ///
  /// The resulting type has a union of the qualifiers from \p T and \c const.
  ///
  /// It can be reasonably expected that this will always be equivalent to
  /// calling T.withConst().
  QualType getConstType(QualType T) const { return T.withConst(); }

  /// Change the ExtInfo on a function type.
  const FunctionType *adjustFunctionType(const FunctionType *Fn,
                                         FunctionType::ExtInfo EInfo);

  /// Adjust the given function result type.
  CanQualType getCanonicalFunctionResultType(QualType ResultType) const;

  /// Change the result type of a function type once it is deduced.
  void adjustDeducedFunctionResultType(FunctionDecl *FD, QualType ResultType);

  /// Get a function type and produce the equivalent function type with the
  /// specified exception specification. Type sugar that can be present on a
  /// declaration of a function with an exception specification is permitted
  /// and preserved. Other type sugar (for instance, typedefs) is not.
  QualType getFunctionTypeWithExceptionSpec(
      QualType Orig, const FunctionProtoType::ExceptionSpecInfo &ESI);

  /// Determine whether two function types are the same, ignoring
  /// exception specifications in cases where they're part of the type.
  bool hasSameFunctionTypeIgnoringExceptionSpec(QualType T, QualType U);

  /// Change the exception specification on a function once it is
  /// delay-parsed, instantiated, or computed.
  void adjustExceptionSpec(FunctionDecl *FD,
                           const FunctionProtoType::ExceptionSpecInfo &ESI,
                           bool AsWritten = false);

  /// Return the uniqued reference to the type for a complex
  /// number with the specified element type.
  QualType getComplexType(QualType T) const;
  CanQualType getComplexType(CanQualType T) const {
    return CanQualType::CreateUnsafe(getComplexType((QualType) T));
  }

  /// Return the uniqued reference to the type for a pointer to
  /// the specified type.
  QualType getPointerType(QualType T) const;
  CanQualType getPointerType(CanQualType T) const {
    return CanQualType::CreateUnsafe(getPointerType((QualType) T));
  }

  /// Return the uniqued reference to a type adjusted from the original
  /// type to a new type.
  QualType getAdjustedType(QualType Orig, QualType New) const;
  CanQualType getAdjustedType(CanQualType Orig, CanQualType New) const {
    return CanQualType::CreateUnsafe(
        getAdjustedType((QualType)Orig, (QualType)New));
  }

  /// Return the uniqued reference to the decayed version of the given
  /// type.  Can only be called on array and function types which decay to
  /// pointer types.
  QualType getDecayedType(QualType T) const;
  CanQualType getDecayedType(CanQualType T) const {
    return CanQualType::CreateUnsafe(getDecayedType((QualType) T));
  }

  /// Return the uniqued reference to the atomic type for the specified
  /// type.
  QualType getAtomicType(QualType T) const;

  /// Return the uniqued reference to the type for a block of the
  /// specified type.
  QualType getBlockPointerType(QualType T) const;

  /// Gets the struct used to keep track of the descriptor for pointer to
  /// blocks.
  QualType getBlockDescriptorType() const;

  /// Return a read_only pipe type for the specified type.
  QualType getReadPipeType(QualType T) const;

  /// Return a write_only pipe type for the specified type.
  QualType getWritePipeType(QualType T) const;

  /// Gets the struct used to keep track of the extended descriptor for
  /// pointer to blocks.
  QualType getBlockDescriptorExtendedType() const;

  /// Map an AST Type to an OpenCLTypeKind enum value.
  TargetInfo::OpenCLTypeKind getOpenCLTypeKind(const Type *T) const;

  /// Get address space for OpenCL type.
  LangAS getOpenCLTypeAddrSpace(const Type *T) const;

  void setcudaConfigureCallDecl(FunctionDecl *FD) {
    cudaConfigureCallDecl = FD;
  }

  FunctionDecl *getcudaConfigureCallDecl() {
    return cudaConfigureCallDecl;
  }

  /// Returns true iff we need copy/dispose helpers for the given type.
  bool BlockRequiresCopying(QualType Ty, const VarDecl *D);

  /// Returns true, if given type has a known lifetime. HasByrefExtendedLayout
  /// is set to false in this case. If HasByrefExtendedLayout returns true,
  /// byref variable has extended lifetime.
  bool getByrefLifetime(QualType Ty,
                        Qualifiers::ObjCLifetime &Lifetime,
                        bool &HasByrefExtendedLayout) const;

  /// Return the uniqued reference to the type for an lvalue reference
  /// to the specified type.
  QualType getLValueReferenceType(QualType T, bool SpelledAsLValue = true)
    const;

  /// Return the uniqued reference to the type for an rvalue reference
  /// to the specified type.
  QualType getRValueReferenceType(QualType T) const;

  /// Return the uniqued reference to the type for a member pointer to
  /// the specified type in the specified class.
  ///
  /// The class \p Cls is a \c Type because it could be a dependent name.
  QualType getMemberPointerType(QualType T, const Type *Cls) const;

  /// Return a non-unique reference to the type for a variable array of
  /// the specified element type.
  QualType getVariableArrayType(QualType EltTy, Expr *NumElts,
                                ArrayType::ArraySizeModifier ASM,
                                unsigned IndexTypeQuals,
                                SourceRange Brackets) const;

  /// Return a non-unique reference to the type for a dependently-sized
  /// array of the specified element type.
  ///
  /// FIXME: We will need these to be uniqued, or at least comparable, at some
  /// point.
  QualType getDependentSizedArrayType(QualType EltTy, Expr *NumElts,
                                      ArrayType::ArraySizeModifier ASM,
                                      unsigned IndexTypeQuals,
                                      SourceRange Brackets) const;

  /// Return a unique reference to the type for an incomplete array of
  /// the specified element type.
  QualType getIncompleteArrayType(QualType EltTy,
                                  ArrayType::ArraySizeModifier ASM,
                                  unsigned IndexTypeQuals) const;

  /// Return the unique reference to the type for a constant array of
  /// the specified element type.
  QualType getConstantArrayType(QualType EltTy, const llvm::APInt &ArySize,
                                ArrayType::ArraySizeModifier ASM,
                                unsigned IndexTypeQuals) const;

  /// Return a type for a constant array for a string literal of the
  /// specified element type and length.
  QualType getStringLiteralArrayType(QualType EltTy, unsigned Length) const;

  /// Returns a vla type where known sizes are replaced with [*].
  QualType getVariableArrayDecayedType(QualType Ty) const;

  /// Return the unique reference to a vector type of the specified
  /// element type and size.
  ///
  /// \pre \p VectorType must be a built-in type.
  QualType getVectorType(QualType VectorType, unsigned NumElts,
                         VectorType::VectorKind VecKind) const;
  /// Return the unique reference to the type for a dependently sized vector of
  /// the specified element type.
  QualType getDependentVectorType(QualType VectorType, Expr *SizeExpr,
                                  SourceLocation AttrLoc,
                                  VectorType::VectorKind VecKind) const;

  /// Return the unique reference to an extended vector type
  /// of the specified element type and size.
  ///
  /// \pre \p VectorType must be a built-in type.
  QualType getExtVectorType(QualType VectorType, unsigned NumElts) const;

  /// \pre Return a non-unique reference to the type for a dependently-sized
  /// vector of the specified element type.
  ///
  /// FIXME: We will need these to be uniqued, or at least comparable, at some
  /// point.
  QualType getDependentSizedExtVectorType(QualType VectorType,
                                          Expr *SizeExpr,
                                          SourceLocation AttrLoc) const;

  QualType getDependentAddressSpaceType(QualType PointeeType,
                                        Expr *AddrSpaceExpr,
                                        SourceLocation AttrLoc) const;

  /// Return a K&R style C function type like 'int()'.
  QualType getFunctionNoProtoType(QualType ResultTy,
                                  const FunctionType::ExtInfo &Info) const;

  QualType getFunctionNoProtoType(QualType ResultTy) const {
    return getFunctionNoProtoType(ResultTy, FunctionType::ExtInfo());
  }

  /// Return a normal function type with a typed argument list.
  QualType getFunctionType(QualType ResultTy, ArrayRef<QualType> Args,
                           const FunctionProtoType::ExtProtoInfo &EPI) const {
    return getFunctionTypeInternal(ResultTy, Args, EPI, false);
  }

  QualType adjustStringLiteralBaseType(QualType StrLTy) const;

private:
  /// Return a normal function type with a typed argument list.
  QualType getFunctionTypeInternal(QualType ResultTy, ArrayRef<QualType> Args,
                                   const FunctionProtoType::ExtProtoInfo &EPI,
                                   bool OnlyWantCanonical) const;

public:
  /// Return the unique reference to the type for the specified type
  /// declaration.
  QualType getTypeDeclType(const TypeDecl *Decl,
                           const TypeDecl *PrevDecl = nullptr) const {
    assert(Decl && "Passed null for Decl param");
    if (Decl->TypeForDecl) return QualType(Decl->TypeForDecl, 0);

    if (PrevDecl) {
      assert(PrevDecl->TypeForDecl && "previous decl has no TypeForDecl");
      Decl->TypeForDecl = PrevDecl->TypeForDecl;
      return QualType(PrevDecl->TypeForDecl, 0);
    }

    return getTypeDeclTypeSlow(Decl);
  }

  /// Return the unique reference to the type for the specified
  /// typedef-name decl.
  QualType getTypedefType(const TypedefNameDecl *Decl,
                          QualType Canon = QualType()) const;

  QualType getRecordType(const RecordDecl *Decl) const;

  QualType getEnumType(const EnumDecl *Decl) const;

  QualType getInjectedClassNameType(CXXRecordDecl *Decl, QualType TST) const;

  QualType getAttributedType(attr::Kind attrKind,
                             QualType modifiedType,
                             QualType equivalentType);

  QualType getSubstTemplateTypeParmType(const TemplateTypeParmType *Replaced,
                                        QualType Replacement) const;
  QualType getSubstTemplateTypeParmPackType(
                                          const TemplateTypeParmType *Replaced,
                                            const TemplateArgument &ArgPack);

  QualType
  getTemplateTypeParmType(unsigned Depth, unsigned Index,
                          bool ParameterPack,
                          TemplateTypeParmDecl *ParmDecl = nullptr) const;

  QualType getTemplateSpecializationType(TemplateName T,
                                         ArrayRef<TemplateArgument> Args,
                                         QualType Canon = QualType()) const;

  QualType
  getCanonicalTemplateSpecializationType(TemplateName T,
                                         ArrayRef<TemplateArgument> Args) const;

  QualType getTemplateSpecializationType(TemplateName T,
                                         const TemplateArgumentListInfo &Args,
                                         QualType Canon = QualType()) const;

  TypeSourceInfo *
  getTemplateSpecializationTypeInfo(TemplateName T, SourceLocation TLoc,
                                    const TemplateArgumentListInfo &Args,
                                    QualType Canon = QualType()) const;

  QualType getParenType(QualType NamedType) const;

  QualType getMacroQualifiedType(QualType UnderlyingTy,
                                 const IdentifierInfo *MacroII) const;

  QualType getElaboratedType(ElaboratedTypeKeyword Keyword,
                             NestedNameSpecifier *NNS, QualType NamedType,
                             TagDecl *OwnedTagDecl = nullptr) const;
  QualType getDependentNameType(ElaboratedTypeKeyword Keyword,
                                NestedNameSpecifier *NNS,
                                const IdentifierInfo *Name,
                                QualType Canon = QualType()) const;

  QualType getDependentTemplateSpecializationType(ElaboratedTypeKeyword Keyword,
                                                  NestedNameSpecifier *NNS,
                                                  const IdentifierInfo *Name,
                                    const TemplateArgumentListInfo &Args) const;
  QualType getDependentTemplateSpecializationType(
      ElaboratedTypeKeyword Keyword, NestedNameSpecifier *NNS,
      const IdentifierInfo *Name, ArrayRef<TemplateArgument> Args) const;

  TemplateArgument getInjectedTemplateArg(NamedDecl *ParamDecl);

  /// Get a template argument list with one argument per template parameter
  /// in a template parameter list, such as for the injected class name of
  /// a class template.
  void getInjectedTemplateArgs(const TemplateParameterList *Params,
                               SmallVectorImpl<TemplateArgument> &Args);

  QualType getPackExpansionType(QualType Pattern,
                                Optional<unsigned> NumExpansions);

  QualType getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
                                ObjCInterfaceDecl *PrevDecl = nullptr) const;

  /// Legacy interface: cannot provide type arguments or __kindof.
  QualType getObjCObjectType(QualType Base,
                             ObjCProtocolDecl * const *Protocols,
                             unsigned NumProtocols) const;

  QualType getObjCObjectType(QualType Base,
                             ArrayRef<QualType> typeArgs,
                             ArrayRef<ObjCProtocolDecl *> protocols,
                             bool isKindOf) const;

  QualType getObjCTypeParamType(const ObjCTypeParamDecl *Decl,
                                ArrayRef<ObjCProtocolDecl *> protocols,
                                QualType Canonical = QualType()) const;

  bool ObjCObjectAdoptsQTypeProtocols(QualType QT, ObjCInterfaceDecl *Decl);

  /// QIdProtocolsAdoptObjCObjectProtocols - Checks that protocols in
  /// QT's qualified-id protocol list adopt all protocols in IDecl's list
  /// of protocols.
  bool QIdProtocolsAdoptObjCObjectProtocols(QualType QT,
                                            ObjCInterfaceDecl *IDecl);

  /// Return a ObjCObjectPointerType type for the given ObjCObjectType.
  QualType getObjCObjectPointerType(QualType OIT) const;

  /// GCC extension.
  QualType getTypeOfExprType(Expr *e) const;
  QualType getTypeOfType(QualType t) const;

  /// C++11 decltype.
  QualType getDecltypeType(Expr *e, QualType UnderlyingType) const;

  /// Unary type transforms
  QualType getUnaryTransformType(QualType BaseType, QualType UnderlyingType,
                                 UnaryTransformType::UTTKind UKind) const;

  /// C++11 deduced auto type.
  QualType getAutoType(QualType DeducedType, AutoTypeKeyword Keyword,
                       bool IsDependent, bool IsPack = false) const;

  /// C++11 deduction pattern for 'auto' type.
  QualType getAutoDeductType() const;

  /// C++11 deduction pattern for 'auto &&' type.
  QualType getAutoRRefDeductType() const;

  /// C++17 deduced class template specialization type.
  QualType getDeducedTemplateSpecializationType(TemplateName Template,
                                                QualType DeducedType,
                                                bool IsDependent) const;

  /// Return the unique reference to the type for the specified TagDecl
  /// (struct/union/class/enum) decl.
  QualType getTagDeclType(const TagDecl *Decl) const;

  /// Return the unique type for "size_t" (C99 7.17), defined in
  /// <stddef.h>.
  ///
  /// The sizeof operator requires this (C99 6.5.3.4p4).
  CanQualType getSizeType() const;

  /// Return the unique signed counterpart of
  /// the integer type corresponding to size_t.
  CanQualType getSignedSizeType() const;

  /// Return the unique type for "intmax_t" (C99 7.18.1.5), defined in
  /// <stdint.h>.
  CanQualType getIntMaxType() const;

  /// Return the unique type for "uintmax_t" (C99 7.18.1.5), defined in
  /// <stdint.h>.
  CanQualType getUIntMaxType() const;

  /// Return the unique wchar_t type available in C++ (and available as
  /// __wchar_t as a Microsoft extension).
  QualType getWCharType() const { return WCharTy; }

  /// Return the type of wide characters. In C++, this returns the
  /// unique wchar_t type. In C99, this returns a type compatible with the type
  /// defined in <stddef.h> as defined by the target.
  QualType getWideCharType() const { return WideCharTy; }

  /// Return the type of "signed wchar_t".
  ///
  /// Used when in C++, as a GCC extension.
  QualType getSignedWCharType() const;

  /// Return the type of "unsigned wchar_t".
  ///
  /// Used when in C++, as a GCC extension.
  QualType getUnsignedWCharType() const;

  /// In C99, this returns a type compatible with the type
  /// defined in <stddef.h> as defined by the target.
  QualType getWIntType() const { return WIntTy; }

  /// Return a type compatible with "intptr_t" (C99 7.18.1.4),
  /// as defined by the target.
  QualType getIntPtrType() const;

  /// Return a type compatible with "uintptr_t" (C99 7.18.1.4),
  /// as defined by the target.
  QualType getUIntPtrType() const;

  /// Return the unique type for "ptrdiff_t" (C99 7.17) defined in
  /// <stddef.h>. Pointer - pointer requires this (C99 6.5.6p9).
  QualType getPointerDiffType() const;

  /// Return the unique unsigned counterpart of "ptrdiff_t"
  /// integer type. The standard (C11 7.21.6.1p7) refers to this type
  /// in the definition of %tu format specifier.
  QualType getUnsignedPointerDiffType() const;

  /// Return the unique type for "pid_t" defined in
  /// <sys/types.h>. We need this to compute the correct type for vfork().
  QualType getProcessIDType() const;

  /// Return the C structure type used to represent constant CFStrings.
  QualType getCFConstantStringType() const;

  /// Returns the C struct type for objc_super
  QualType getObjCSuperType() const;
  void setObjCSuperType(QualType ST) { ObjCSuperType = ST; }

  /// Get the structure type used to representation CFStrings, or NULL
  /// if it hasn't yet been built.
  QualType getRawCFConstantStringType() const {
    if (CFConstantStringTypeDecl)
      return getTypedefType(CFConstantStringTypeDecl);
    return QualType();
  }
  void setCFConstantStringType(QualType T);
  TypedefDecl *getCFConstantStringDecl() const;
  RecordDecl *getCFConstantStringTagDecl() const;

  // This setter/getter represents the ObjC type for an NSConstantString.
  void setObjCConstantStringInterface(ObjCInterfaceDecl *Decl);
  QualType getObjCConstantStringInterface() const {
    return ObjCConstantStringType;
  }

  QualType getObjCNSStringType() const {
    return ObjCNSStringType;
  }

  void setObjCNSStringType(QualType T) {
    ObjCNSStringType = T;
  }

  /// Retrieve the type that \c id has been defined to, which may be
  /// different from the built-in \c id if \c id has been typedef'd.
  QualType getObjCIdRedefinitionType() const {
    if (ObjCIdRedefinitionType.isNull())
      return getObjCIdType();
    return ObjCIdRedefinitionType;
  }

  /// Set the user-written type that redefines \c id.
  void setObjCIdRedefinitionType(QualType RedefType) {
    ObjCIdRedefinitionType = RedefType;
  }

  /// Retrieve the type that \c Class has been defined to, which may be
  /// different from the built-in \c Class if \c Class has been typedef'd.
  QualType getObjCClassRedefinitionType() const {
    if (ObjCClassRedefinitionType.isNull())
      return getObjCClassType();
    return ObjCClassRedefinitionType;
  }

  /// Set the user-written type that redefines 'SEL'.
  void setObjCClassRedefinitionType(QualType RedefType) {
    ObjCClassRedefinitionType = RedefType;
  }

  /// Retrieve the type that 'SEL' has been defined to, which may be
  /// different from the built-in 'SEL' if 'SEL' has been typedef'd.
  QualType getObjCSelRedefinitionType() const {
    if (ObjCSelRedefinitionType.isNull())
      return getObjCSelType();
    return ObjCSelRedefinitionType;
  }

  /// Set the user-written type that redefines 'SEL'.
  void setObjCSelRedefinitionType(QualType RedefType) {
    ObjCSelRedefinitionType = RedefType;
  }

  /// Retrieve the identifier 'NSObject'.
  IdentifierInfo *getNSObjectName() const {
    if (!NSObjectName) {
      NSObjectName = &Idents.get("NSObject");
    }

    return NSObjectName;
  }

  /// Retrieve the identifier 'NSCopying'.
  IdentifierInfo *getNSCopyingName() {
    if (!NSCopyingName) {
      NSCopyingName = &Idents.get("NSCopying");
    }

    return NSCopyingName;
  }

  CanQualType getNSUIntegerType() const {
    assert(Target && "Expected target to be initialized");
    const llvm::Triple &T = Target->getTriple();
    // Windows is LLP64 rather than LP64
    if (T.isOSWindows() && T.isArch64Bit())
      return UnsignedLongLongTy;
    return UnsignedLongTy;
  }

  CanQualType getNSIntegerType() const {
    assert(Target && "Expected target to be initialized");
    const llvm::Triple &T = Target->getTriple();
    // Windows is LLP64 rather than LP64
    if (T.isOSWindows() && T.isArch64Bit())
      return LongLongTy;
    return LongTy;
  }

  /// Retrieve the identifier 'bool'.
  IdentifierInfo *getBoolName() const {
    if (!BoolName)
      BoolName = &Idents.get("bool");
    return BoolName;
  }

  IdentifierInfo *getMakeIntegerSeqName() const {
    if (!MakeIntegerSeqName)
      MakeIntegerSeqName = &Idents.get("__make_integer_seq");
    return MakeIntegerSeqName;
  }

  IdentifierInfo *getTypePackElementName() const {
    if (!TypePackElementName)
      TypePackElementName = &Idents.get("__type_pack_element");
    return TypePackElementName;
  }

  /// Retrieve the Objective-C "instancetype" type, if already known;
  /// otherwise, returns a NULL type;
  QualType getObjCInstanceType() {
    return getTypeDeclType(getObjCInstanceTypeDecl());
  }

  /// Retrieve the typedef declaration corresponding to the Objective-C
  /// "instancetype" type.
  TypedefDecl *getObjCInstanceTypeDecl();

  /// Set the type for the C FILE type.
  void setFILEDecl(TypeDecl *FILEDecl) { this->FILEDecl = FILEDecl; }

  /// Retrieve the C FILE type.
  QualType getFILEType() const {
    if (FILEDecl)
      return getTypeDeclType(FILEDecl);
    return QualType();
  }

  /// Set the type for the C jmp_buf type.
  void setjmp_bufDecl(TypeDecl *jmp_bufDecl) {
    this->jmp_bufDecl = jmp_bufDecl;
  }

  /// Retrieve the C jmp_buf type.
  QualType getjmp_bufType() const {
    if (jmp_bufDecl)
      return getTypeDeclType(jmp_bufDecl);
    return QualType();
  }

  /// Set the type for the C sigjmp_buf type.
  void setsigjmp_bufDecl(TypeDecl *sigjmp_bufDecl) {
    this->sigjmp_bufDecl = sigjmp_bufDecl;
  }

  /// Retrieve the C sigjmp_buf type.
  QualType getsigjmp_bufType() const {
    if (sigjmp_bufDecl)
      return getTypeDeclType(sigjmp_bufDecl);
    return QualType();
  }

  /// Set the type for the C ucontext_t type.
  void setucontext_tDecl(TypeDecl *ucontext_tDecl) {
    this->ucontext_tDecl = ucontext_tDecl;
  }

  /// Retrieve the C ucontext_t type.
  QualType getucontext_tType() const {
    if (ucontext_tDecl)
      return getTypeDeclType(ucontext_tDecl);
    return QualType();
  }

  /// The result type of logical operations, '<', '>', '!=', etc.
  QualType getLogicalOperationType() const {
    return getLangOpts().CPlusPlus ? BoolTy : IntTy;
  }

  /// Emit the Objective-CC type encoding for the given type \p T into
  /// \p S.
  ///
  /// If \p Field is specified then record field names are also encoded.
  void getObjCEncodingForType(QualType T, std::string &S,
                              const FieldDecl *Field=nullptr,
                              QualType *NotEncodedT=nullptr) const;

  /// Emit the Objective-C property type encoding for the given
  /// type \p T into \p S.
  void getObjCEncodingForPropertyType(QualType T, std::string &S) const;

  void getLegacyIntegralTypeEncoding(QualType &t) const;

  /// Put the string version of the type qualifiers \p QT into \p S.
  void getObjCEncodingForTypeQualifier(Decl::ObjCDeclQualifier QT,
                                       std::string &S) const;

  /// Emit the encoded type for the function \p Decl into \p S.
  ///
  /// This is in the same format as Objective-C method encodings.
  ///
  /// \returns true if an error occurred (e.g., because one of the parameter
  /// types is incomplete), false otherwise.
  std::string getObjCEncodingForFunctionDecl(const FunctionDecl *Decl) const;

  /// Emit the encoded type for the method declaration \p Decl into
  /// \p S.
  std::string getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl,
                                           bool Extended = false) const;

  /// Return the encoded type for this block declaration.
  std::string getObjCEncodingForBlock(const BlockExpr *blockExpr) const;

  /// getObjCEncodingForPropertyDecl - Return the encoded type for
  /// this method declaration. If non-NULL, Container must be either
  /// an ObjCCategoryImplDecl or ObjCImplementationDecl; it should
  /// only be NULL when getting encodings for protocol properties.
  std::string getObjCEncodingForPropertyDecl(const ObjCPropertyDecl *PD,
                                             const Decl *Container) const;

  bool ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
                                      ObjCProtocolDecl *rProto) const;

  ObjCPropertyImplDecl *getObjCPropertyImplDeclForPropertyDecl(
                                                  const ObjCPropertyDecl *PD,
                                                  const Decl *Container) const;

  /// Return the size of type \p T for Objective-C encoding purpose,
  /// in characters.
  CharUnits getObjCEncodingTypeSize(QualType T) const;

  /// Retrieve the typedef corresponding to the predefined \c id type
  /// in Objective-C.
  TypedefDecl *getObjCIdDecl() const;

  /// Represents the Objective-CC \c id type.
  ///
  /// This is set up lazily, by Sema.  \c id is always a (typedef for a)
  /// pointer type, a pointer to a struct.
  QualType getObjCIdType() const {
    return getTypeDeclType(getObjCIdDecl());
  }

  /// Retrieve the typedef corresponding to the predefined 'SEL' type
  /// in Objective-C.
  TypedefDecl *getObjCSelDecl() const;

  /// Retrieve the type that corresponds to the predefined Objective-C
  /// 'SEL' type.
  QualType getObjCSelType() const {
    return getTypeDeclType(getObjCSelDecl());
  }

  /// Retrieve the typedef declaration corresponding to the predefined
  /// Objective-C 'Class' type.
  TypedefDecl *getObjCClassDecl() const;

  /// Represents the Objective-C \c Class type.
  ///
  /// This is set up lazily, by Sema.  \c Class is always a (typedef for a)
  /// pointer type, a pointer to a struct.
  QualType getObjCClassType() const {
    return getTypeDeclType(getObjCClassDecl());
  }

  /// Retrieve the Objective-C class declaration corresponding to
  /// the predefined \c Protocol class.
  ObjCInterfaceDecl *getObjCProtocolDecl() const;

  /// Retrieve declaration of 'BOOL' typedef
  TypedefDecl *getBOOLDecl() const {
    return BOOLDecl;
  }

  /// Save declaration of 'BOOL' typedef
  void setBOOLDecl(TypedefDecl *TD) {
    BOOLDecl = TD;
  }

  /// type of 'BOOL' type.
  QualType getBOOLType() const {
    return getTypeDeclType(getBOOLDecl());
  }

  /// Retrieve the type of the Objective-C \c Protocol class.
  QualType getObjCProtoType() const {
    return getObjCInterfaceType(getObjCProtocolDecl());
  }

  /// Retrieve the C type declaration corresponding to the predefined
  /// \c __builtin_va_list type.
  TypedefDecl *getBuiltinVaListDecl() const;

  /// Retrieve the type of the \c __builtin_va_list type.
  QualType getBuiltinVaListType() const {
    return getTypeDeclType(getBuiltinVaListDecl());
  }

  /// Retrieve the C type declaration corresponding to the predefined
  /// \c __va_list_tag type used to help define the \c __builtin_va_list type
  /// for some targets.
  Decl *getVaListTagDecl() const;

  /// Retrieve the C type declaration corresponding to the predefined
  /// \c __builtin_ms_va_list type.
  TypedefDecl *getBuiltinMSVaListDecl() const;

  /// Retrieve the type of the \c __builtin_ms_va_list type.
  QualType getBuiltinMSVaListType() const {
    return getTypeDeclType(getBuiltinMSVaListDecl());
  }

  /// Return whether a declaration to a builtin is allowed to be
  /// overloaded/redeclared.
  bool canBuiltinBeRedeclared(const FunctionDecl *) const;

  /// Return a type with additional \c const, \c volatile, or
  /// \c restrict qualifiers.
  QualType getCVRQualifiedType(QualType T, unsigned CVR) const {
    return getQualifiedType(T, Qualifiers::fromCVRMask(CVR));
  }

  /// Un-split a SplitQualType.
  QualType getQualifiedType(SplitQualType split) const {
    return getQualifiedType(split.Ty, split.Quals);
  }

  /// Return a type with additional qualifiers.
  QualType getQualifiedType(QualType T, Qualifiers Qs) const {
    if (!Qs.hasNonFastQualifiers())
      return T.withFastQualifiers(Qs.getFastQualifiers());
    QualifierCollector Qc(Qs);
    const Type *Ptr = Qc.strip(T);
    return getExtQualType(Ptr, Qc);
  }

  /// Return a type with additional qualifiers.
  QualType getQualifiedType(const Type *T, Qualifiers Qs) const {
    if (!Qs.hasNonFastQualifiers())
      return QualType(T, Qs.getFastQualifiers());
    return getExtQualType(T, Qs);
  }

  /// Return a type with the given lifetime qualifier.
  ///
  /// \pre Neither type.ObjCLifetime() nor \p lifetime may be \c OCL_None.
  QualType getLifetimeQualifiedType(QualType type,
                                    Qualifiers::ObjCLifetime lifetime) {
    assert(type.getObjCLifetime() == Qualifiers::OCL_None);
    assert(lifetime != Qualifiers::OCL_None);

    Qualifiers qs;
    qs.addObjCLifetime(lifetime);
    return getQualifiedType(type, qs);
  }

  /// getUnqualifiedObjCPointerType - Returns version of
  /// Objective-C pointer type with lifetime qualifier removed.
  QualType getUnqualifiedObjCPointerType(QualType type) const {
    if (!type.getTypePtr()->isObjCObjectPointerType() ||
        !type.getQualifiers().hasObjCLifetime())
      return type;
    Qualifiers Qs = type.getQualifiers();
    Qs.removeObjCLifetime();
    return getQualifiedType(type.getUnqualifiedType(), Qs);
  }

  unsigned char getFixedPointScale(QualType Ty) const;
  unsigned char getFixedPointIBits(QualType Ty) const;
  FixedPointSemantics getFixedPointSemantics(QualType Ty) const;
  APFixedPoint getFixedPointMax(QualType Ty) const;
  APFixedPoint getFixedPointMin(QualType Ty) const;

  DeclarationNameInfo getNameForTemplate(TemplateName Name,
                                         SourceLocation NameLoc) const;

  TemplateName getOverloadedTemplateName(UnresolvedSetIterator Begin,
                                         UnresolvedSetIterator End) const;
  TemplateName getAssumedTemplateName(DeclarationName Name) const;

  TemplateName getQualifiedTemplateName(NestedNameSpecifier *NNS,
                                        bool TemplateKeyword,
                                        TemplateDecl *Template) const;

  TemplateName getDependentTemplateName(NestedNameSpecifier *NNS,
                                        const IdentifierInfo *Name) const;
  TemplateName getDependentTemplateName(NestedNameSpecifier *NNS,
                                        OverloadedOperatorKind Operator) const;
  TemplateName getSubstTemplateTemplateParm(TemplateTemplateParmDecl *param,
                                            TemplateName replacement) const;
  TemplateName getSubstTemplateTemplateParmPack(TemplateTemplateParmDecl *Param,
                                        const TemplateArgument &ArgPack) const;

  enum GetBuiltinTypeError {
    /// No error
    GE_None,

    /// Missing a type
    GE_Missing_type,

    /// Missing a type from <stdio.h>
    GE_Missing_stdio,

    /// Missing a type from <setjmp.h>
    GE_Missing_setjmp,

    /// Missing a type from <ucontext.h>
    GE_Missing_ucontext
  };

  /// Return the type for the specified builtin.
  ///
  /// If \p IntegerConstantArgs is non-null, it is filled in with a bitmask of
  /// arguments to the builtin that are required to be integer constant
  /// expressions.
  QualType GetBuiltinType(unsigned ID, GetBuiltinTypeError &Error,
                          unsigned *IntegerConstantArgs = nullptr) const;

  /// Types and expressions required to build C++2a three-way comparisons
  /// using operator<=>, including the values return by builtin <=> operators.
  ComparisonCategories CompCategories;

private:
  CanQualType getFromTargetType(unsigned Type) const;
  TypeInfo getTypeInfoImpl(const Type *T) const;

  //===--------------------------------------------------------------------===//
  //                         Type Predicates.
  //===--------------------------------------------------------------------===//

public:
  /// Return one of the GCNone, Weak or Strong Objective-C garbage
  /// collection attributes.
  Qualifiers::GC getObjCGCAttrKind(QualType Ty) const;

  /// Return true if the given vector types are of the same unqualified
  /// type or if they are equivalent to the same GCC vector type.
  ///
  /// \note This ignores whether they are target-specific (AltiVec or Neon)
  /// types.
  bool areCompatibleVectorTypes(QualType FirstVec, QualType SecondVec);

  /// Return true if the type has been explicitly qualified with ObjC ownership.
  /// A type may be implicitly qualified with ownership under ObjC ARC, and in
  /// some cases the compiler treats these differently.
  bool hasDirectOwnershipQualifier(QualType Ty) const;

  /// Return true if this is an \c NSObject object with its \c NSObject
  /// attribute set.
  static bool isObjCNSObjectType(QualType Ty) {
    return Ty->isObjCNSObjectType();
  }

  //===--------------------------------------------------------------------===//
  //                         Type Sizing and Analysis
  //===--------------------------------------------------------------------===//

  /// Return the APFloat 'semantics' for the specified scalar floating
  /// point type.
  const llvm::fltSemantics &getFloatTypeSemantics(QualType T) const;

  /// Get the size and alignment of the specified complete type in bits.
  TypeInfo getTypeInfo(const Type *T) const;
  TypeInfo getTypeInfo(QualType T) const { return getTypeInfo(T.getTypePtr()); }

  /// Get default simd alignment of the specified complete type in bits.
  unsigned getOpenMPDefaultSimdAlign(QualType T) const;

  /// Return the size of the specified (complete) type \p T, in bits.
  uint64_t getTypeSize(QualType T) const { return getTypeInfo(T).Width; }
  uint64_t getTypeSize(const Type *T) const { return getTypeInfo(T).Width; }

  /// Return the size of the character type, in bits.
  uint64_t getCharWidth() const {
    return getTypeSize(CharTy);
  }

  /// Convert a size in bits to a size in characters.
  CharUnits toCharUnitsFromBits(int64_t BitSize) const;

  /// Convert a size in characters to a size in bits.
  int64_t toBits(CharUnits CharSize) const;

  /// Return the size of the specified (complete) type \p T, in
  /// characters.
  CharUnits getTypeSizeInChars(QualType T) const;
  CharUnits getTypeSizeInChars(const Type *T) const;

  Optional<CharUnits> getTypeSizeInCharsIfKnown(QualType Ty) const {
    if (Ty->isIncompleteType() || Ty->isDependentType())
      return None;
    return getTypeSizeInChars(Ty);
  }

  Optional<CharUnits> getTypeSizeInCharsIfKnown(const Type *Ty) const {
    return getTypeSizeInCharsIfKnown(QualType(Ty, 0));
  }

  /// Return the ABI-specified alignment of a (complete) type \p T, in
  /// bits.
  unsigned getTypeAlign(QualType T) const { return getTypeInfo(T).Align; }
  unsigned getTypeAlign(const Type *T) const { return getTypeInfo(T).Align; }

  /// Return the ABI-specified natural alignment of a (complete) type \p T,
  /// before alignment adjustments, in bits.
  ///
  /// This alignment is curently used only by ARM and AArch64 when passing
  /// arguments of a composite type.
  unsigned getTypeUnadjustedAlign(QualType T) const {
    return getTypeUnadjustedAlign(T.getTypePtr());
  }
  unsigned getTypeUnadjustedAlign(const Type *T) const;

  /// Return the ABI-specified alignment of a type, in bits, or 0 if
  /// the type is incomplete and we cannot determine the alignment (for
  /// example, from alignment attributes).
  unsigned getTypeAlignIfKnown(QualType T) const;

  /// Return the ABI-specified alignment of a (complete) type \p T, in
  /// characters.
  CharUnits getTypeAlignInChars(QualType T) const;
  CharUnits getTypeAlignInChars(const Type *T) const;

  /// getTypeUnadjustedAlignInChars - Return the ABI-specified alignment of a type,
  /// in characters, before alignment adjustments. This method does not work on
  /// incomplete types.
  CharUnits getTypeUnadjustedAlignInChars(QualType T) const;
  CharUnits getTypeUnadjustedAlignInChars(const Type *T) const;

  // getTypeInfoDataSizeInChars - Return the size of a type, in chars. If the
  // type is a record, its data size is returned.
  std::pair<CharUnits, CharUnits> getTypeInfoDataSizeInChars(QualType T) const;

  std::pair<CharUnits, CharUnits> getTypeInfoInChars(const Type *T) const;
  std::pair<CharUnits, CharUnits> getTypeInfoInChars(QualType T) const;

  /// Determine if the alignment the type has was required using an
  /// alignment attribute.
  bool isAlignmentRequired(const Type *T) const;
  bool isAlignmentRequired(QualType T) const;

  /// Return the "preferred" alignment of the specified type \p T for
  /// the current target, in bits.
  ///
  /// This can be different than the ABI alignment in cases where it is
  /// beneficial for performance to overalign a data type.
  unsigned getPreferredTypeAlign(const Type *T) const;

  /// Return the default alignment for __attribute__((aligned)) on
  /// this target, to be used if no alignment value is specified.
  unsigned getTargetDefaultAlignForAttributeAligned() const;

  /// Return the alignment in bits that should be given to a
  /// global variable with type \p T.
  unsigned getAlignOfGlobalVar(QualType T) const;

  /// Return the alignment in characters that should be given to a
  /// global variable with type \p T.
  CharUnits getAlignOfGlobalVarInChars(QualType T) const;

  /// Return a conservative estimate of the alignment of the specified
  /// decl \p D.
  ///
  /// \pre \p D must not be a bitfield type, as bitfields do not have a valid
  /// alignment.
  ///
  /// If \p ForAlignof, references are treated like their underlying type
  /// and  large arrays don't get any special treatment. If not \p ForAlignof
  /// it computes the value expected by CodeGen: references are treated like
  /// pointers and large arrays get extra alignment.
  CharUnits getDeclAlign(const Decl *D, bool ForAlignof = false) const;

  /// Return the alignment (in bytes) of the thrown exception object. This is
  /// only meaningful for targets that allocate C++ exceptions in a system
  /// runtime, such as those using the Itanium C++ ABI.
  CharUnits getExnObjectAlignment() const {
    return toCharUnitsFromBits(Target->getExnObjectAlignment());
  }

  /// Get or compute information about the layout of the specified
  /// record (struct/union/class) \p D, which indicates its size and field
  /// position information.
  const ASTRecordLayout &getASTRecordLayout(const RecordDecl *D) const;

  /// Get or compute information about the layout of the specified
  /// Objective-C interface.
  const ASTRecordLayout &getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D)
    const;

  void DumpRecordLayout(const RecordDecl *RD, raw_ostream &OS,
                        bool Simple = false) const;

  /// Get or compute information about the layout of the specified
  /// Objective-C implementation.
  ///
  /// This may differ from the interface if synthesized ivars are present.
  const ASTRecordLayout &
  getASTObjCImplementationLayout(const ObjCImplementationDecl *D) const;

  /// Get our current best idea for the key function of the
  /// given record decl, or nullptr if there isn't one.
  ///
  /// The key function is, according to the Itanium C++ ABI section 5.2.3:
  ///   ...the first non-pure virtual function that is not inline at the
  ///   point of class definition.
  ///
  /// Other ABIs use the same idea.  However, the ARM C++ ABI ignores
  /// virtual functions that are defined 'inline', which means that
  /// the result of this computation can change.
  const CXXMethodDecl *getCurrentKeyFunction(const CXXRecordDecl *RD);

  /// Observe that the given method cannot be a key function.
  /// Checks the key-function cache for the method's class and clears it
  /// if matches the given declaration.
  ///
  /// This is used in ABIs where out-of-line definitions marked
  /// inline are not considered to be key functions.
  ///
  /// \param method should be the declaration from the class definition
  void setNonKeyFunction(const CXXMethodDecl *method);

  /// Loading virtual member pointers using the virtual inheritance model
  /// always results in an adjustment using the vbtable even if the index is
  /// zero.
  ///
  /// This is usually OK because the first slot in the vbtable points
  /// backwards to the top of the MDC.  However, the MDC might be reusing a
  /// vbptr from an nv-base.  In this case, the first slot in the vbtable
  /// points to the start of the nv-base which introduced the vbptr and *not*
  /// the MDC.  Modify the NonVirtualBaseAdjustment to account for this.
  CharUnits getOffsetOfBaseWithVBPtr(const CXXRecordDecl *RD) const;

  /// Get the offset of a FieldDecl or IndirectFieldDecl, in bits.
  uint64_t getFieldOffset(const ValueDecl *FD) const;

  /// Get the offset of an ObjCIvarDecl in bits.
  uint64_t lookupFieldBitOffset(const ObjCInterfaceDecl *OID,
                                const ObjCImplementationDecl *ID,
                                const ObjCIvarDecl *Ivar) const;

  bool isNearlyEmpty(const CXXRecordDecl *RD) const;

  VTableContextBase *getVTableContext();

  /// If \p T is null pointer, assume the target in ASTContext.
  MangleContext *createMangleContext(const TargetInfo *T = nullptr);

  void DeepCollectObjCIvars(const ObjCInterfaceDecl *OI, bool leafClass,
                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const;

  unsigned CountNonClassIvars(const ObjCInterfaceDecl *OI) const;
  void CollectInheritedProtocols(const Decl *CDecl,
                          llvm::SmallPtrSet<ObjCProtocolDecl*, 8> &Protocols);

  /// Return true if the specified type has unique object representations
  /// according to (C++17 [meta.unary.prop]p9)
  bool hasUniqueObjectRepresentations(QualType Ty) const;

  //===--------------------------------------------------------------------===//
  //                            Type Operators
  //===--------------------------------------------------------------------===//

  /// Return the canonical (structural) type corresponding to the
  /// specified potentially non-canonical type \p T.
  ///
  /// The non-canonical version of a type may have many "decorated" versions of
  /// types.  Decorators can include typedefs, 'typeof' operators, etc. The
  /// returned type is guaranteed to be free of any of these, allowing two
  /// canonical types to be compared for exact equality with a simple pointer
  /// comparison.
  CanQualType getCanonicalType(QualType T) const {
    return CanQualType::CreateUnsafe(T.getCanonicalType());
  }

  const Type *getCanonicalType(const Type *T) const {
    return T->getCanonicalTypeInternal().getTypePtr();
  }

  /// Return the canonical parameter type corresponding to the specific
  /// potentially non-canonical one.
  ///
  /// Qualifiers are stripped off, functions are turned into function
  /// pointers, and arrays decay one level into pointers.
  CanQualType getCanonicalParamType(QualType T) const;

  /// Determine whether the given types \p T1 and \p T2 are equivalent.
  bool hasSameType(QualType T1, QualType T2) const {
    return getCanonicalType(T1) == getCanonicalType(T2);
  }
  bool hasSameType(const Type *T1, const Type *T2) const {
    return getCanonicalType(T1) == getCanonicalType(T2);
  }

  /// Return this type as a completely-unqualified array type,
  /// capturing the qualifiers in \p Quals.
  ///
  /// This will remove the minimal amount of sugaring from the types, similar
  /// to the behavior of QualType::getUnqualifiedType().
  ///
  /// \param T is the qualified type, which may be an ArrayType
  ///
  /// \param Quals will receive the full set of qualifiers that were
  /// applied to the array.
  ///
  /// \returns if this is an array type, the completely unqualified array type
  /// that corresponds to it. Otherwise, returns T.getUnqualifiedType().
  QualType getUnqualifiedArrayType(QualType T, Qualifiers &Quals);

  /// Determine whether the given types are equivalent after
  /// cvr-qualifiers have been removed.
  bool hasSameUnqualifiedType(QualType T1, QualType T2) const {
    return getCanonicalType(T1).getTypePtr() ==
           getCanonicalType(T2).getTypePtr();
  }

  bool hasSameNullabilityTypeQualifier(QualType SubT, QualType SuperT,
                                       bool IsParam) const {
    auto SubTnullability = SubT->getNullability(*this);
    auto SuperTnullability = SuperT->getNullability(*this);
    if (SubTnullability.hasValue() == SuperTnullability.hasValue()) {
      // Neither has nullability; return true
      if (!SubTnullability)
        return true;
      // Both have nullability qualifier.
      if (*SubTnullability == *SuperTnullability ||
          *SubTnullability == NullabilityKind::Unspecified ||
          *SuperTnullability == NullabilityKind::Unspecified)
        return true;

      if (IsParam) {
        // Ok for the superclass method parameter to be "nonnull" and the subclass
        // method parameter to be "nullable"
        return (*SuperTnullability == NullabilityKind::NonNull &&
                *SubTnullability == NullabilityKind::Nullable);
      }
      else {
        // For the return type, it's okay for the superclass method to specify
        // "nullable" and the subclass method specify "nonnull"
        return (*SuperTnullability == NullabilityKind::Nullable &&
                *SubTnullability == NullabilityKind::NonNull);
      }
    }
    return true;
  }

  bool ObjCMethodsAreEqual(const ObjCMethodDecl *MethodDecl,
                           const ObjCMethodDecl *MethodImp);

  bool UnwrapSimilarTypes(QualType &T1, QualType &T2);
  bool UnwrapSimilarArrayTypes(QualType &T1, QualType &T2);

  /// Determine if two types are similar, according to the C++ rules. That is,
  /// determine if they are the same other than qualifiers on the initial
  /// sequence of pointer / pointer-to-member / array (and in Clang, object
  /// pointer) types and their element types.
  ///
  /// Clang offers a number of qualifiers in addition to the C++ qualifiers;
  /// those qualifiers are also ignored in the 'similarity' check.
  bool hasSimilarType(QualType T1, QualType T2);

  /// Determine if two types are similar, ignoring only CVR qualifiers.
  bool hasCvrSimilarType(QualType T1, QualType T2);

  /// Retrieves the "canonical" nested name specifier for a
  /// given nested name specifier.
  ///
  /// The canonical nested name specifier is a nested name specifier
  /// that uniquely identifies a type or namespace within the type
  /// system. For example, given:
  ///
  /// \code
  /// namespace N {
  ///   struct S {
  ///     template<typename T> struct X { typename T* type; };
  ///   };
  /// }
  ///
  /// template<typename T> struct Y {
  ///   typename N::S::X<T>::type member;
  /// };
  /// \endcode
  ///
  /// Here, the nested-name-specifier for N::S::X<T>:: will be
  /// S::X<template-param-0-0>, since 'S' and 'X' are uniquely defined
  /// by declarations in the type system and the canonical type for
  /// the template type parameter 'T' is template-param-0-0.
  NestedNameSpecifier *
  getCanonicalNestedNameSpecifier(NestedNameSpecifier *NNS) const;

  /// Retrieves the default calling convention for the current target.
  CallingConv getDefaultCallingConvention(bool IsVariadic,
                                          bool IsCXXMethod,
                                          bool IsBuiltin = false) const;

  /// Retrieves the "canonical" template name that refers to a
  /// given template.
  ///
  /// The canonical template name is the simplest expression that can
  /// be used to refer to a given template. For most templates, this
  /// expression is just the template declaration itself. For example,
  /// the template std::vector can be referred to via a variety of
  /// names---std::vector, \::std::vector, vector (if vector is in
  /// scope), etc.---but all of these names map down to the same
  /// TemplateDecl, which is used to form the canonical template name.
  ///
  /// Dependent template names are more interesting. Here, the
  /// template name could be something like T::template apply or
  /// std::allocator<T>::template rebind, where the nested name
  /// specifier itself is dependent. In this case, the canonical
  /// template name uses the shortest form of the dependent
  /// nested-name-specifier, which itself contains all canonical
  /// types, values, and templates.
  TemplateName getCanonicalTemplateName(TemplateName Name) const;

  /// Determine whether the given template names refer to the same
  /// template.
  bool hasSameTemplateName(TemplateName X, TemplateName Y);

  /// Retrieve the "canonical" template argument.
  ///
  /// The canonical template argument is the simplest template argument
  /// (which may be a type, value, expression, or declaration) that
  /// expresses the value of the argument.
  TemplateArgument getCanonicalTemplateArgument(const TemplateArgument &Arg)
    const;

  /// Type Query functions.  If the type is an instance of the specified class,
  /// return the Type pointer for the underlying maximally pretty type.  This
  /// is a member of ASTContext because this may need to do some amount of
  /// canonicalization, e.g. to move type qualifiers into the element type.
  const ArrayType *getAsArrayType(QualType T) const;
  const ConstantArrayType *getAsConstantArrayType(QualType T) const {
    return dyn_cast_or_null<ConstantArrayType>(getAsArrayType(T));
  }
  const VariableArrayType *getAsVariableArrayType(QualType T) const {
    return dyn_cast_or_null<VariableArrayType>(getAsArrayType(T));
  }
  const IncompleteArrayType *getAsIncompleteArrayType(QualType T) const {
    return dyn_cast_or_null<IncompleteArrayType>(getAsArrayType(T));
  }
  const DependentSizedArrayType *getAsDependentSizedArrayType(QualType T)
    const {
    return dyn_cast_or_null<DependentSizedArrayType>(getAsArrayType(T));
  }

  /// Return the innermost element type of an array type.
  ///
  /// For example, will return "int" for int[m][n]
  QualType getBaseElementType(const ArrayType *VAT) const;

  /// Return the innermost element type of a type (which needn't
  /// actually be an array type).
  QualType getBaseElementType(QualType QT) const;

  /// Return number of constant array elements.
  uint64_t getConstantArrayElementCount(const ConstantArrayType *CA) const;

  /// Perform adjustment on the parameter type of a function.
  ///
  /// This routine adjusts the given parameter type @p T to the actual
  /// parameter type used by semantic analysis (C99 6.7.5.3p[7,8],
  /// C++ [dcl.fct]p3). The adjusted parameter type is returned.
  QualType getAdjustedParameterType(QualType T) const;

  /// Retrieve the parameter type as adjusted for use in the signature
  /// of a function, decaying array and function types and removing top-level
  /// cv-qualifiers.
  QualType getSignatureParameterType(QualType T) const;

  QualType getExceptionObjectType(QualType T) const;

  /// Return the properly qualified result of decaying the specified
  /// array type to a pointer.
  ///
  /// This operation is non-trivial when handling typedefs etc.  The canonical
  /// type of \p T must be an array type, this returns a pointer to a properly
  /// qualified element of the array.
  ///
  /// See C99 6.7.5.3p7 and C99 6.3.2.1p3.
  QualType getArrayDecayedType(QualType T) const;

  /// Return the type that \p PromotableType will promote to: C99
  /// 6.3.1.1p2, assuming that \p PromotableType is a promotable integer type.
  QualType getPromotedIntegerType(QualType PromotableType) const;

  /// Recurses in pointer/array types until it finds an Objective-C
  /// retainable type and returns its ownership.
  Qualifiers::ObjCLifetime getInnerObjCOwnership(QualType T) const;

  /// Whether this is a promotable bitfield reference according
  /// to C99 6.3.1.1p2, bullet 2 (and GCC extensions).
  ///
  /// \returns the type this bit-field will promote to, or NULL if no
  /// promotion occurs.
  QualType isPromotableBitField(Expr *E) const;

  /// Return the highest ranked integer type, see C99 6.3.1.8p1.
  ///
  /// If \p LHS > \p RHS, returns 1.  If \p LHS == \p RHS, returns 0.  If
  /// \p LHS < \p RHS, return -1.
  int getIntegerTypeOrder(QualType LHS, QualType RHS) const;

  /// Compare the rank of the two specified floating point types,
  /// ignoring the domain of the type (i.e. 'double' == '_Complex double').
  ///
  /// If \p LHS > \p RHS, returns 1.  If \p LHS == \p RHS, returns 0.  If
  /// \p LHS < \p RHS, return -1.
  int getFloatingTypeOrder(QualType LHS, QualType RHS) const;

  /// Compare the rank of two floating point types as above, but compare equal
  /// if both types have the same floating-point semantics on the target (i.e.
  /// long double and double on AArch64 will return 0).
  int getFloatingTypeSemanticOrder(QualType LHS, QualType RHS) const;

  /// Return a real floating point or a complex type (based on
  /// \p typeDomain/\p typeSize).
  ///
  /// \param typeDomain a real floating point or complex type.
  /// \param typeSize a real floating point or complex type.
  QualType getFloatingTypeOfSizeWithinDomain(QualType typeSize,
                                             QualType typeDomain) const;

  unsigned getTargetAddressSpace(QualType T) const {
    return getTargetAddressSpace(T.getQualifiers());
  }

  unsigned getTargetAddressSpace(Qualifiers Q) const {
    return getTargetAddressSpace(Q.getAddressSpace());
  }

  unsigned getTargetAddressSpace(LangAS AS) const;

  LangAS getLangASForBuiltinAddressSpace(unsigned AS) const;

  /// Get target-dependent integer value for null pointer which is used for
  /// constant folding.
  uint64_t getTargetNullPointerValue(QualType QT) const;

  bool addressSpaceMapManglingFor(LangAS AS) const {
    return AddrSpaceMapMangling || isTargetAddressSpace(AS);
  }

private:
  // Helper for integer ordering
  unsigned getIntegerRank(const Type *T) const;

public:
  //===--------------------------------------------------------------------===//
  //                    Type Compatibility Predicates
  //===--------------------------------------------------------------------===//

  /// Compatibility predicates used to check assignment expressions.
  bool typesAreCompatible(QualType T1, QualType T2,
                          bool CompareUnqualified = false); // C99 6.2.7p1

  bool propertyTypesAreCompatible(QualType, QualType);
  bool typesAreBlockPointerCompatible(QualType, QualType);

  bool isObjCIdType(QualType T) const {
    return T == getObjCIdType();
  }

  bool isObjCClassType(QualType T) const {
    return T == getObjCClassType();
  }

  bool isObjCSelType(QualType T) const {
    return T == getObjCSelType();
  }

  bool ObjCQualifiedIdTypesAreCompatible(const ObjCObjectPointerType *LHS,
                                         const ObjCObjectPointerType *RHS,
                                         bool ForCompare);

  bool ObjCQualifiedClassTypesAreCompatible(const ObjCObjectPointerType *LHS,
                                            const ObjCObjectPointerType *RHS);

  // Check the safety of assignment from LHS to RHS
  bool canAssignObjCInterfaces(const ObjCObjectPointerType *LHSOPT,
                               const ObjCObjectPointerType *RHSOPT);
  bool canAssignObjCInterfaces(const ObjCObjectType *LHS,
                               const ObjCObjectType *RHS);
  bool canAssignObjCInterfacesInBlockPointer(
                                          const ObjCObjectPointerType *LHSOPT,
                                          const ObjCObjectPointerType *RHSOPT,
                                          bool BlockReturnType);
  bool areComparableObjCPointerTypes(QualType LHS, QualType RHS);
  QualType areCommonBaseCompatible(const ObjCObjectPointerType *LHSOPT,
                                   const ObjCObjectPointerType *RHSOPT);
  bool canBindObjCObjectType(QualType To, QualType From);

  // Functions for calculating composite types
  QualType mergeTypes(QualType, QualType, bool OfBlockPointer=false,
                      bool Unqualified = false, bool BlockReturnType = false);
  QualType mergeFunctionTypes(QualType, QualType, bool OfBlockPointer=false,
                              bool Unqualified = false);
  QualType mergeFunctionParameterTypes(QualType, QualType,
                                       bool OfBlockPointer = false,
                                       bool Unqualified = false);
  QualType mergeTransparentUnionType(QualType, QualType,
                                     bool OfBlockPointer=false,
                                     bool Unqualified = false);

  QualType mergeObjCGCQualifiers(QualType, QualType);

  /// This function merges the ExtParameterInfo lists of two functions. It
  /// returns true if the lists are compatible. The merged list is returned in
  /// NewParamInfos.
  ///
  /// \param FirstFnType The type of the first function.
  ///
  /// \param SecondFnType The type of the second function.
  ///
  /// \param CanUseFirst This flag is set to true if the first function's
  /// ExtParameterInfo list can be used as the composite list of
  /// ExtParameterInfo.
  ///
  /// \param CanUseSecond This flag is set to true if the second function's
  /// ExtParameterInfo list can be used as the composite list of
  /// ExtParameterInfo.
  ///
  /// \param NewParamInfos The composite list of ExtParameterInfo. The list is
  /// empty if none of the flags are set.
  ///
  bool mergeExtParameterInfo(
      const FunctionProtoType *FirstFnType,
      const FunctionProtoType *SecondFnType,
      bool &CanUseFirst, bool &CanUseSecond,
      SmallVectorImpl<FunctionProtoType::ExtParameterInfo> &NewParamInfos);

  void ResetObjCLayout(const ObjCContainerDecl *CD);

  //===--------------------------------------------------------------------===//
  //                    Integer Predicates
  //===--------------------------------------------------------------------===//

  // The width of an integer, as defined in C99 6.2.6.2. This is the number
  // of bits in an integer type excluding any padding bits.
  unsigned getIntWidth(QualType T) const;

  // Per C99 6.2.5p6, for every signed integer type, there is a corresponding
  // unsigned integer type.  This method takes a signed type, and returns the
  // corresponding unsigned integer type.
  // With the introduction of fixed point types in ISO N1169, this method also
  // accepts fixed point types and returns the corresponding unsigned type for
  // a given fixed point type.
  QualType getCorrespondingUnsignedType(QualType T) const;

  // Per ISO N1169, this method accepts fixed point types and returns the
  // corresponding saturated type for a given fixed point type.
  QualType getCorrespondingSaturatedType(QualType Ty) const;

  // This method accepts fixed point types and returns the corresponding signed
  // type. Unlike getCorrespondingUnsignedType(), this only accepts unsigned
  // fixed point types because there are unsigned integer types like bool and
  // char8_t that don't have signed equivalents.
  QualType getCorrespondingSignedFixedPointType(QualType Ty) const;

  //===--------------------------------------------------------------------===//
  //                    Integer Values
  //===--------------------------------------------------------------------===//

  /// Make an APSInt of the appropriate width and signedness for the
  /// given \p Value and integer \p Type.
  llvm::APSInt MakeIntValue(uint64_t Value, QualType Type) const {
    // If Type is a signed integer type larger than 64 bits, we need to be sure
    // to sign extend Res appropriately.
    llvm::APSInt Res(64, !Type->isSignedIntegerOrEnumerationType());
    Res = Value;
    unsigned Width = getIntWidth(Type);
    if (Width != Res.getBitWidth())
      return Res.extOrTrunc(Width);
    return Res;
  }

  bool isSentinelNullExpr(const Expr *E);

  /// Get the implementation of the ObjCInterfaceDecl \p D, or nullptr if
  /// none exists.
  ObjCImplementationDecl *getObjCImplementation(ObjCInterfaceDecl *D);

  /// Get the implementation of the ObjCCategoryDecl \p D, or nullptr if
  /// none exists.
  ObjCCategoryImplDecl *getObjCImplementation(ObjCCategoryDecl *D);

  /// Return true if there is at least one \@implementation in the TU.
  bool AnyObjCImplementation() {
    return !ObjCImpls.empty();
  }

  /// Set the implementation of ObjCInterfaceDecl.
  void setObjCImplementation(ObjCInterfaceDecl *IFaceD,
                             ObjCImplementationDecl *ImplD);

  /// Set the implementation of ObjCCategoryDecl.
  void setObjCImplementation(ObjCCategoryDecl *CatD,
                             ObjCCategoryImplDecl *ImplD);

  /// Get the duplicate declaration of a ObjCMethod in the same
  /// interface, or null if none exists.
  const ObjCMethodDecl *
  getObjCMethodRedeclaration(const ObjCMethodDecl *MD) const;

  void setObjCMethodRedeclaration(const ObjCMethodDecl *MD,
                                  const ObjCMethodDecl *Redecl);

  /// Returns the Objective-C interface that \p ND belongs to if it is
  /// an Objective-C method/property/ivar etc. that is part of an interface,
  /// otherwise returns null.
  const ObjCInterfaceDecl *getObjContainingInterface(const NamedDecl *ND) const;

  /// Set the copy initialization expression of a block var decl. \p CanThrow
  /// indicates whether the copy expression can throw or not.
  void setBlockVarCopyInit(const VarDecl* VD, Expr *CopyExpr, bool CanThrow);

  /// Get the copy initialization expression of the VarDecl \p VD, or
  /// nullptr if none exists.
  BlockVarCopyInit getBlockVarCopyInit(const VarDecl* VD) const;

  /// Allocate an uninitialized TypeSourceInfo.
  ///
  /// The caller should initialize the memory held by TypeSourceInfo using
  /// the TypeLoc wrappers.
  ///
  /// \param T the type that will be the basis for type source info. This type
  /// should refer to how the declarator was written in source code, not to
  /// what type semantic analysis resolved the declarator to.
  ///
  /// \param Size the size of the type info to create, or 0 if the size
  /// should be calculated based on the type.
  TypeSourceInfo *CreateTypeSourceInfo(QualType T, unsigned Size = 0) const;

  /// Allocate a TypeSourceInfo where all locations have been
  /// initialized to a given location, which defaults to the empty
  /// location.
  TypeSourceInfo *
  getTrivialTypeSourceInfo(QualType T,
                           SourceLocation Loc = SourceLocation()) const;

  /// Add a deallocation callback that will be invoked when the
  /// ASTContext is destroyed.
  ///
  /// \param Callback A callback function that will be invoked on destruction.
  ///
  /// \param Data Pointer data that will be provided to the callback function
  /// when it is called.
  void AddDeallocation(void (*Callback)(void *), void *Data) const;

  /// If T isn't trivially destructible, calls AddDeallocation to register it
  /// for destruction.
  template <typename T> void addDestruction(T *Ptr) const {
    if (!std::is_trivially_destructible<T>::value) {
      auto DestroyPtr = [](void *V) { static_cast<T *>(V)->~T(); };
      AddDeallocation(DestroyPtr, Ptr);
    }
  }

  GVALinkage GetGVALinkageForFunction(const FunctionDecl *FD) const;
  GVALinkage GetGVALinkageForVariable(const VarDecl *VD);

  /// Determines if the decl can be CodeGen'ed or deserialized from PCH
  /// lazily, only when used; this is only relevant for function or file scoped
  /// var definitions.
  ///
  /// \returns true if the function/var must be CodeGen'ed/deserialized even if
  /// it is not used.
  bool DeclMustBeEmitted(const Decl *D);

  /// Visits all versions of a multiversioned function with the passed
  /// predicate.
  void forEachMultiversionedFunctionVersion(
      const FunctionDecl *FD,
      llvm::function_ref<void(FunctionDecl *)> Pred) const;

  const CXXConstructorDecl *
  getCopyConstructorForExceptionObject(CXXRecordDecl *RD);

  void addCopyConstructorForExceptionObject(CXXRecordDecl *RD,
                                            CXXConstructorDecl *CD);

  void addTypedefNameForUnnamedTagDecl(TagDecl *TD, TypedefNameDecl *TND);

  TypedefNameDecl *getTypedefNameForUnnamedTagDecl(const TagDecl *TD);

  void addDeclaratorForUnnamedTagDecl(TagDecl *TD, DeclaratorDecl *DD);

  DeclaratorDecl *getDeclaratorForUnnamedTagDecl(const TagDecl *TD);

  void setManglingNumber(const NamedDecl *ND, unsigned Number);
  unsigned getManglingNumber(const NamedDecl *ND) const;

  void setStaticLocalNumber(const VarDecl *VD, unsigned Number);
  unsigned getStaticLocalNumber(const VarDecl *VD) const;

  /// Retrieve the context for computing mangling numbers in the given
  /// DeclContext.
  MangleNumberingContext &getManglingNumberContext(const DeclContext *DC);

  std::unique_ptr<MangleNumberingContext> createMangleNumberingContext() const;

  /// Used by ParmVarDecl to store on the side the
  /// index of the parameter when it exceeds the size of the normal bitfield.
  void setParameterIndex(const ParmVarDecl *D, unsigned index);

  /// Used by ParmVarDecl to retrieve on the side the
  /// index of the parameter when it exceeds the size of the normal bitfield.
  unsigned getParameterIndex(const ParmVarDecl *D) const;

  /// Get the storage for the constant value of a materialized temporary
  /// of static storage duration.
  APValue *getMaterializedTemporaryValue(const MaterializeTemporaryExpr *E,
                                         bool MayCreate);

  /// Return a string representing the human readable name for the specified
  /// function declaration or file name. Used by SourceLocExpr and
  /// PredefinedExpr to cache evaluated results.
  StringLiteral *getPredefinedStringLiteralFromCache(StringRef Key) const;

  //===--------------------------------------------------------------------===//
  //                    Statistics
  //===--------------------------------------------------------------------===//

  /// The number of implicitly-declared default constructors.
  unsigned NumImplicitDefaultConstructors = 0;

  /// The number of implicitly-declared default constructors for
  /// which declarations were built.
  unsigned NumImplicitDefaultConstructorsDeclared = 0;

  /// The number of implicitly-declared copy constructors.
  unsigned NumImplicitCopyConstructors = 0;

  /// The number of implicitly-declared copy constructors for
  /// which declarations were built.
  unsigned NumImplicitCopyConstructorsDeclared = 0;

  /// The number of implicitly-declared move constructors.
  unsigned NumImplicitMoveConstructors = 0;

  /// The number of implicitly-declared move constructors for
  /// which declarations were built.
  unsigned NumImplicitMoveConstructorsDeclared = 0;

  /// The number of implicitly-declared copy assignment operators.
  unsigned NumImplicitCopyAssignmentOperators = 0;

  /// The number of implicitly-declared copy assignment operators for
  /// which declarations were built.
  unsigned NumImplicitCopyAssignmentOperatorsDeclared = 0;

  /// The number of implicitly-declared move assignment operators.
  unsigned NumImplicitMoveAssignmentOperators = 0;

  /// The number of implicitly-declared move assignment operators for
  /// which declarations were built.
  unsigned NumImplicitMoveAssignmentOperatorsDeclared = 0;

  /// The number of implicitly-declared destructors.
  unsigned NumImplicitDestructors = 0;

  /// The number of implicitly-declared destructors for which
  /// declarations were built.
  unsigned NumImplicitDestructorsDeclared = 0;

public:
  /// Initialize built-in types.
  ///
  /// This routine may only be invoked once for a given ASTContext object.
  /// It is normally invoked after ASTContext construction.
  ///
  /// \param Target The target
  void InitBuiltinTypes(const TargetInfo &Target,
                        const TargetInfo *AuxTarget = nullptr);

private:
  void InitBuiltinType(CanQualType &R, BuiltinType::Kind K);

  class ObjCEncOptions {
    unsigned Bits;

    ObjCEncOptions(unsigned Bits) : Bits(Bits) {}

  public:
    ObjCEncOptions() : Bits(0) {}
    ObjCEncOptions(const ObjCEncOptions &RHS) : Bits(RHS.Bits) {}

#define OPT_LIST(V)                                                            \
  V(ExpandPointedToStructures, 0)                                              \
  V(ExpandStructures, 1)                                                       \
  V(IsOutermostType, 2)                                                        \
  V(EncodingProperty, 3)                                                       \
  V(IsStructField, 4)                                                          \
  V(EncodeBlockParameters, 5)                                                  \
  V(EncodeClassNames, 6)                                                       \

#define V(N,I) ObjCEncOptions& set##N() { Bits |= 1 << I; return *this; }
OPT_LIST(V)
#undef V

#define V(N,I) bool N() const { return Bits & 1 << I; }
OPT_LIST(V)
#undef V

#undef OPT_LIST

    LLVM_NODISCARD ObjCEncOptions keepingOnly(ObjCEncOptions Mask) const {
      return Bits & Mask.Bits;
    }

    LLVM_NODISCARD ObjCEncOptions forComponentType() const {
      ObjCEncOptions Mask = ObjCEncOptions()
                                .setIsOutermostType()
                                .setIsStructField();
      return Bits & ~Mask.Bits;
    }
  };

  // Return the Objective-C type encoding for a given type.
  void getObjCEncodingForTypeImpl(QualType t, std::string &S,
                                  ObjCEncOptions Options,
                                  const FieldDecl *Field,
                                  QualType *NotEncodedT = nullptr) const;

  // Adds the encoding of the structure's members.
  void getObjCEncodingForStructureImpl(RecordDecl *RD, std::string &S,
                                       const FieldDecl *Field,
                                       bool includeVBases = true,
                                       QualType *NotEncodedT=nullptr) const;

public:
  // Adds the encoding of a method parameter or return type.
  void getObjCEncodingForMethodParameter(Decl::ObjCDeclQualifier QT,
                                         QualType T, std::string& S,
                                         bool Extended) const;

  /// Returns true if this is an inline-initialized static data member
  /// which is treated as a definition for MSVC compatibility.
  bool isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const;

  enum class InlineVariableDefinitionKind {
    /// Not an inline variable.
    None,

    /// Weak definition of inline variable.
    Weak,

    /// Weak for now, might become strong later in this TU.
    WeakUnknown,

    /// Strong definition.
    Strong
  };

  /// Determine whether a definition of this inline variable should
  /// be treated as a weak or strong definition. For compatibility with
  /// C++14 and before, for a constexpr static data member, if there is an
  /// out-of-line declaration of the member, we may promote it from weak to
  /// strong.
  InlineVariableDefinitionKind
  getInlineVariableDefinitionKind(const VarDecl *VD) const;

private:
  friend class DeclarationNameTable;
  friend class DeclContext;

  const ASTRecordLayout &
  getObjCLayout(const ObjCInterfaceDecl *D,
                const ObjCImplementationDecl *Impl) const;

  /// A set of deallocations that should be performed when the
  /// ASTContext is destroyed.
  // FIXME: We really should have a better mechanism in the ASTContext to
  // manage running destructors for types which do variable sized allocation
  // within the AST. In some places we thread the AST bump pointer allocator
  // into the datastructures which avoids this mess during deallocation but is
  // wasteful of memory, and here we require a lot of error prone book keeping
  // in order to track and run destructors while we're tearing things down.
  using DeallocationFunctionsAndArguments =
      llvm::SmallVector<std::pair<void (*)(void *), void *>, 16>;
  mutable DeallocationFunctionsAndArguments Deallocations;

  // FIXME: This currently contains the set of StoredDeclMaps used
  // by DeclContext objects.  This probably should not be in ASTContext,
  // but we include it here so that ASTContext can quickly deallocate them.
  llvm::PointerIntPair<StoredDeclsMap *, 1> LastSDM;

  std::vector<Decl *> TraversalScope;
  class ParentMap;
  std::unique_ptr<ParentMap> Parents;

  std::unique_ptr<VTableContextBase> VTContext;

  void ReleaseDeclContextMaps();

public:
  enum PragmaSectionFlag : unsigned {
    PSF_None = 0,
    PSF_Read = 0x1,
    PSF_Write = 0x2,
    PSF_Execute = 0x4,
    PSF_Implicit = 0x8,
    PSF_Invalid = 0x80000000U,
  };

  struct SectionInfo {
    DeclaratorDecl *Decl;
    SourceLocation PragmaSectionLocation;
    int SectionFlags;

    SectionInfo() = default;
    SectionInfo(DeclaratorDecl *Decl,
                SourceLocation PragmaSectionLocation,
                int SectionFlags)
        : Decl(Decl), PragmaSectionLocation(PragmaSectionLocation),
          SectionFlags(SectionFlags) {}
  };

  llvm::StringMap<SectionInfo> SectionInfos;
};

/// Utility function for constructing a nullary selector.
inline Selector GetNullarySelector(StringRef name, ASTContext &Ctx) {
  IdentifierInfo* II = &Ctx.Idents.get(name);
  return Ctx.Selectors.getSelector(0, &II);
}

/// Utility function for constructing an unary selector.
inline Selector GetUnarySelector(StringRef name, ASTContext &Ctx) {
  IdentifierInfo* II = &Ctx.Idents.get(name);
  return Ctx.Selectors.getSelector(1, &II);
}

} // namespace clang

// operator new and delete aren't allowed inside namespaces.

/// Placement new for using the ASTContext's allocator.
///
/// This placement form of operator new uses the ASTContext's allocator for
/// obtaining memory.
///
/// IMPORTANT: These are also declared in clang/AST/ASTContextAllocate.h!
/// Any changes here need to also be made there.
///
/// We intentionally avoid using a nothrow specification here so that the calls
/// to this operator will not perform a null check on the result -- the
/// underlying allocator never returns null pointers.
///
/// Usage looks like this (assuming there's an ASTContext 'Context' in scope):
/// @code
/// // Default alignment (8)
/// IntegerLiteral *Ex = new (Context) IntegerLiteral(arguments);
/// // Specific alignment
/// IntegerLiteral *Ex2 = new (Context, 4) IntegerLiteral(arguments);
/// @endcode
/// Memory allocated through this placement new operator does not need to be
/// explicitly freed, as ASTContext will free all of this memory when it gets
/// destroyed. Please note that you cannot use delete on the pointer.
///
/// @param Bytes The number of bytes to allocate. Calculated by the compiler.
/// @param C The ASTContext that provides the allocator.
/// @param Alignment The alignment of the allocated memory (if the underlying
///                  allocator supports it).
/// @return The allocated memory. Could be nullptr.
inline void *operator new(size_t Bytes, const clang::ASTContext &C,
                          size_t Alignment /* = 8 */) {
  return C.Allocate(Bytes, Alignment);
}

/// Placement delete companion to the new above.
///
/// This operator is just a companion to the new above. There is no way of
/// invoking it directly; see the new operator for more details. This operator
/// is called implicitly by the compiler if a placement new expression using
/// the ASTContext throws in the object constructor.
inline void operator delete(void *Ptr, const clang::ASTContext &C, size_t) {
  C.Deallocate(Ptr);
}

/// This placement form of operator new[] uses the ASTContext's allocator for
/// obtaining memory.
///
/// We intentionally avoid using a nothrow specification here so that the calls
/// to this operator will not perform a null check on the result -- the
/// underlying allocator never returns null pointers.
///
/// Usage looks like this (assuming there's an ASTContext 'Context' in scope):
/// @code
/// // Default alignment (8)
/// char *data = new (Context) char[10];
/// // Specific alignment
/// char *data = new (Context, 4) char[10];
/// @endcode
/// Memory allocated through this placement new[] operator does not need to be
/// explicitly freed, as ASTContext will free all of this memory when it gets
/// destroyed. Please note that you cannot use delete on the pointer.
///
/// @param Bytes The number of bytes to allocate. Calculated by the compiler.
/// @param C The ASTContext that provides the allocator.
/// @param Alignment The alignment of the allocated memory (if the underlying
///                  allocator supports it).
/// @return The allocated memory. Could be nullptr.
inline void *operator new[](size_t Bytes, const clang::ASTContext& C,
                            size_t Alignment /* = 8 */) {
  return C.Allocate(Bytes, Alignment);
}

/// Placement delete[] companion to the new[] above.
///
/// This operator is just a companion to the new[] above. There is no way of
/// invoking it directly; see the new[] operator for more details. This operator
/// is called implicitly by the compiler if a placement new[] expression using
/// the ASTContext throws in the object constructor.
inline void operator delete[](void *Ptr, const clang::ASTContext &C, size_t) {
  C.Deallocate(Ptr);
}

/// Create the representation of a LazyGenerationalUpdatePtr.
template <typename Owner, typename T,
          void (clang::ExternalASTSource::*Update)(Owner)>
typename clang::LazyGenerationalUpdatePtr<Owner, T, Update>::ValueType
    clang::LazyGenerationalUpdatePtr<Owner, T, Update>::makeValue(
        const clang::ASTContext &Ctx, T Value) {
  // Note, this is implemented here so that ExternalASTSource.h doesn't need to
  // include ASTContext.h. We explicitly instantiate it for all relevant types
  // in ASTContext.cpp.
  if (auto *Source = Ctx.getExternalSource())
    return new (Ctx) LazyData(Source, Value);
  return Value;
}

#endif // LLVM_CLANG_AST_ASTCONTEXT_H