aboutsummaryrefslogtreecommitdiff
path: root/mesalib/src/glsl/ir.h
blob: 7859702ed015c7d2d2464048da2500d0f36030bb (plain)
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
/* -*- c++ -*- */
/*
 * Copyright © 2010 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#pragma once
#ifndef IR_H
#define IR_H

#include <stdio.h>
#include <stdlib.h>

#include "ralloc.h"
#include "glsl_types.h"
#include "list.h"
#include "ir_visitor.h"
#include "ir_hierarchical_visitor.h"
#include "main/mtypes.h"

#ifdef __cplusplus

/**
 * \defgroup IR Intermediate representation nodes
 *
 * @{
 */

/**
 * Class tags
 *
 * Each concrete class derived from \c ir_instruction has a value in this
 * enumerant.  The value for the type is stored in \c ir_instruction::ir_type
 * by the constructor.  While using type tags is not very C++, it is extremely
 * convenient.  For example, during debugging you can simply inspect
 * \c ir_instruction::ir_type to find out the actual type of the object.
 *
 * In addition, it is possible to use a switch-statement based on \c
 * \c ir_instruction::ir_type to select different behavior for different object
 * types.  For functions that have only slight differences for several object
 * types, this allows writing very straightforward, readable code.
 */
enum ir_node_type {
   /**
    * Zero is unused so that the IR validator can detect cases where
    * \c ir_instruction::ir_type has not been initialized.
    */
   ir_type_unset,
   ir_type_variable,
   ir_type_assignment,
   ir_type_call,
   ir_type_constant,
   ir_type_dereference_array,
   ir_type_dereference_record,
   ir_type_dereference_variable,
   ir_type_discard,
   ir_type_expression,
   ir_type_function,
   ir_type_function_signature,
   ir_type_if,
   ir_type_loop,
   ir_type_loop_jump,
   ir_type_return,
   ir_type_swizzle,
   ir_type_texture,
   ir_type_emit_vertex,
   ir_type_end_primitive,
   ir_type_max /**< maximum ir_type enum number, for validation */
};

/**
 * Base class of all IR instructions
 */
class ir_instruction : public exec_node {
public:
   enum ir_node_type ir_type;

   /**
    * GCC 4.7+ and clang warn when deleting an ir_instruction unless
    * there's a virtual destructor present.  Because we almost
    * universally use ralloc for our memory management of
    * ir_instructions, the destructor doesn't need to do any work.
    */
   virtual ~ir_instruction()
   {
   }

   /** ir_print_visitor helper for debugging. */
   void print(void) const;

   virtual void accept(ir_visitor *) = 0;
   virtual ir_visitor_status accept(ir_hierarchical_visitor *) = 0;
   virtual ir_instruction *clone(void *mem_ctx,
				 struct hash_table *ht) const = 0;

   /**
    * \name IR instruction downcast functions
    *
    * These functions either cast the object to a derived class or return
    * \c NULL if the object's type does not match the specified derived class.
    * Additional downcast functions will be added as needed.
    */
   /*@{*/
   virtual class ir_variable *          as_variable()         { return NULL; }
   virtual class ir_function *          as_function()         { return NULL; }
   virtual class ir_dereference *       as_dereference()      { return NULL; }
   virtual class ir_dereference_array *	as_dereference_array() { return NULL; }
   virtual class ir_dereference_variable *as_dereference_variable() { return NULL; }
   virtual class ir_dereference_record *as_dereference_record() { return NULL; }
   virtual class ir_expression *        as_expression()       { return NULL; }
   virtual class ir_rvalue *            as_rvalue()           { return NULL; }
   virtual class ir_loop *              as_loop()             { return NULL; }
   virtual class ir_assignment *        as_assignment()       { return NULL; }
   virtual class ir_call *              as_call()             { return NULL; }
   virtual class ir_return *            as_return()           { return NULL; }
   virtual class ir_if *                as_if()               { return NULL; }
   virtual class ir_swizzle *           as_swizzle()          { return NULL; }
   virtual class ir_texture *           as_texture()          { return NULL; }
   virtual class ir_constant *          as_constant()         { return NULL; }
   virtual class ir_discard *           as_discard()          { return NULL; }
   virtual class ir_jump *              as_jump()             { return NULL; }
   /*@}*/

   /**
    * IR equality method: Return true if the referenced instruction would
    * return the same value as this one.
    *
    * This intended to be used for CSE and algebraic optimizations, on rvalues
    * in particular.  No support for other instruction types (assignments,
    * jumps, calls, etc.) is planned.
    */
   virtual bool equals(ir_instruction *ir);

protected:
   ir_instruction()
   {
      ir_type = ir_type_unset;
   }
};


/**
 * The base class for all "values"/expression trees.
 */
class ir_rvalue : public ir_instruction {
public:
   const struct glsl_type *type;

   virtual ir_rvalue *clone(void *mem_ctx, struct hash_table *) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   virtual ir_rvalue * as_rvalue()
   {
      return this;
   }

   ir_rvalue *as_rvalue_to_saturate();

   virtual bool is_lvalue() const
   {
      return false;
   }

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced() const
   {
      return NULL;
   }


   /**
    * If an r-value is a reference to a whole variable, get that variable
    *
    * \return
    * Pointer to a variable that is completely dereferenced by the r-value.  If
    * the r-value is not a dereference or the dereference does not access the
    * entire variable (i.e., it's just one array element, struct field), \c NULL
    * is returned.
    */
   virtual ir_variable *whole_variable_referenced()
   {
      return NULL;
   }

   /**
    * Determine if an r-value has the value zero
    *
    * The base implementation of this function always returns \c false.  The
    * \c ir_constant class over-rides this function to return \c true \b only
    * for vector and scalar types that have all elements set to the value
    * zero (or \c false for booleans).
    *
    * \sa ir_constant::has_value, ir_rvalue::is_one, ir_rvalue::is_negative_one,
    *     ir_constant::is_basis
    */
   virtual bool is_zero() const;

   /**
    * Determine if an r-value has the value one
    *
    * The base implementation of this function always returns \c false.  The
    * \c ir_constant class over-rides this function to return \c true \b only
    * for vector and scalar types that have all elements set to the value
    * one (or \c true for booleans).
    *
    * \sa ir_constant::has_value, ir_rvalue::is_zero, ir_rvalue::is_negative_one,
    *     ir_constant::is_basis
    */
   virtual bool is_one() const;

   /**
    * Determine if an r-value has the value negative one
    *
    * The base implementation of this function always returns \c false.  The
    * \c ir_constant class over-rides this function to return \c true \b only
    * for vector and scalar types that have all elements set to the value
    * negative one.  For boolean types, the result is always \c false.
    *
    * \sa ir_constant::has_value, ir_rvalue::is_zero, ir_rvalue::is_one
    *     ir_constant::is_basis
    */
   virtual bool is_negative_one() const;

   /**
    * Determine if an r-value is a basis vector
    *
    * The base implementation of this function always returns \c false.  The
    * \c ir_constant class over-rides this function to return \c true \b only
    * for vector and scalar types that have one element set to the value one,
    * and the other elements set to the value zero.  For boolean types, the
    * result is always \c false.
    *
    * \sa ir_constant::has_value, ir_rvalue::is_zero, ir_rvalue::is_one,
    *     is_constant::is_negative_one
    */
   virtual bool is_basis() const;


   /**
    * Return a generic value of error_type.
    *
    * Allocation will be performed with 'mem_ctx' as ralloc owner.
    */
   static ir_rvalue *error_value(void *mem_ctx);

protected:
   ir_rvalue();
};


/**
 * Variable storage classes
 */
enum ir_variable_mode {
   ir_var_auto = 0,     /**< Function local variables and globals. */
   ir_var_uniform,      /**< Variable declared as a uniform. */
   ir_var_shader_in,
   ir_var_shader_out,
   ir_var_function_in,
   ir_var_function_out,
   ir_var_function_inout,
   ir_var_const_in,	/**< "in" param that must be a constant expression */
   ir_var_system_value, /**< Ex: front-face, instance-id, etc. */
   ir_var_temporary,	/**< Temporary variable generated during compilation. */
   ir_var_mode_count	/**< Number of variable modes */
};

/**
 * \brief Layout qualifiers for gl_FragDepth.
 *
 * The AMD/ARB_conservative_depth extensions allow gl_FragDepth to be redeclared
 * with a layout qualifier.
 */
enum ir_depth_layout {
    ir_depth_layout_none, /**< No depth layout is specified. */
    ir_depth_layout_any,
    ir_depth_layout_greater,
    ir_depth_layout_less,
    ir_depth_layout_unchanged
};

/**
 * \brief Convert depth layout qualifier to string.
 */
const char*
depth_layout_string(ir_depth_layout layout);

/**
 * Description of built-in state associated with a uniform
 *
 * \sa ir_variable::state_slots
 */
struct ir_state_slot {
   int tokens[5];
   int swizzle;
};


/**
 * Get the string value for an interpolation qualifier
 *
 * \return The string that would be used in a shader to specify \c
 * mode will be returned.
 *
 * This function is used to generate error messages of the form "shader
 * uses %s interpolation qualifier", so in the case where there is no
 * interpolation qualifier, it returns "no".
 *
 * This function should only be used on a shader input or output variable.
 */
const char *interpolation_string(unsigned interpolation);


class ir_variable : public ir_instruction {
public:
   ir_variable(const struct glsl_type *, const char *, ir_variable_mode);

   virtual ir_variable *clone(void *mem_ctx, struct hash_table *ht) const;

   virtual ir_variable *as_variable()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);


   /**
    * Determine how this variable should be interpolated based on its
    * interpolation qualifier (if present), whether it is gl_Color or
    * gl_SecondaryColor, and whether flatshading is enabled in the current GL
    * state.
    *
    * The return value will always be either INTERP_QUALIFIER_SMOOTH,
    * INTERP_QUALIFIER_NOPERSPECTIVE, or INTERP_QUALIFIER_FLAT.
    */
   glsl_interp_qualifier determine_interpolation_mode(bool flat_shade);

   /**
    * Determine whether or not a variable is part of a uniform block.
    */
   inline bool is_in_uniform_block() const
   {
      return this->mode == ir_var_uniform && this->interface_type != NULL;
   }

   /**
    * Determine whether or not a variable is the declaration of an interface
    * block
    *
    * For the first declaration below, there will be an \c ir_variable named
    * "instance" whose type and whose instance_type will be the same
    *  \cglsl_type.  For the second declaration, there will be an \c ir_variable
    * named "f" whose type is float and whose instance_type is B2.
    *
    * "instance" is an interface instance variable, but "f" is not.
    *
    * uniform B1 {
    *     float f;
    * } instance;
    *
    * uniform B2 {
    *     float f;
    * };
    */
   inline bool is_interface_instance() const
   {
      const glsl_type *const t = this->type;

      return (t == this->interface_type)
         || (t->is_array() && t->fields.array == this->interface_type);
    }

   /**
    * Set this->interface_type on a newly created variable.
    */
   void init_interface_type(const struct glsl_type *type)
   {
      assert(this->interface_type == NULL);
      this->interface_type = type;
      if (this->is_interface_instance()) {
         this->max_ifc_array_access =
            rzalloc_array(this, unsigned, type->length);
      }
   }

   /**
    * Change this->interface_type on a variable that previously had a
    * different, but compatible, interface_type.  This is used during linking
    * to set the size of arrays in interface blocks.
    */
   void change_interface_type(const struct glsl_type *type)
   {
      if (this->max_ifc_array_access != NULL) {
         /* max_ifc_array_access has already been allocated, so make sure the
          * new interface has the same number of fields as the old one.
          */
         assert(this->interface_type->length == type->length);
      }
      this->interface_type = type;
   }

   /**
    * Change this->interface_type on a variable that previously had a
    * different, and incompatible, interface_type. This is used during
    * compilation to handle redeclaration of the built-in gl_PerVertex
    * interface block.
    */
   void reinit_interface_type(const struct glsl_type *type)
   {
      if (this->max_ifc_array_access != NULL) {
#ifndef _NDEBUG
         /* Redeclaring gl_PerVertex is only allowed if none of the built-ins
          * it defines have been accessed yet; so it's safe to throw away the
          * old max_ifc_array_access pointer, since all of its values are
          * zero.
          */
         for (unsigned i = 0; i < this->interface_type->length; i++)
            assert(this->max_ifc_array_access[i] == 0);
#endif
         ralloc_free(this->max_ifc_array_access);
         this->max_ifc_array_access = NULL;
      }
      this->interface_type = NULL;
      init_interface_type(type);
   }

   const glsl_type *get_interface_type() const
   {
      return this->interface_type;
   }

   /**
    * Declared type of the variable
    */
   const struct glsl_type *type;

   /**
    * Declared name of the variable
    */
   const char *name;

   /**
    * Highest element accessed with a constant expression array index
    *
    * Not used for non-array variables.
    */
   unsigned max_array_access;

   /**
    * For variables which satisfy the is_interface_instance() predicate, this
    * points to an array of integers such that if the ith member of the
    * interface block is an array, max_ifc_array_access[i] is the maximum
    * array element of that member that has been accessed.  If the ith member
    * of the interface block is not an array, max_ifc_array_access[i] is
    * unused.
    *
    * For variables whose type is not an interface block, this pointer is
    * NULL.
    */
   unsigned *max_ifc_array_access;

   /**
    * Is the variable read-only?
    *
    * This is set for variables declared as \c const, shader inputs,
    * and uniforms.
    */
   unsigned read_only:1;
   unsigned centroid:1;
   unsigned invariant:1;

   /**
    * Has this variable been used for reading or writing?
    *
    * Several GLSL semantic checks require knowledge of whether or not a
    * variable has been used.  For example, it is an error to redeclare a
    * variable as invariant after it has been used.
    *
    * This is only maintained in the ast_to_hir.cpp path, not in
    * Mesa's fixed function or ARB program paths.
    */
   unsigned used:1;

   /**
    * Has this variable been statically assigned?
    *
    * This answers whether the variable was assigned in any path of
    * the shader during ast_to_hir.  This doesn't answer whether it is
    * still written after dead code removal, nor is it maintained in
    * non-ast_to_hir.cpp (GLSL parsing) paths.
    */
   unsigned assigned:1;

   /**
    * Storage class of the variable.
    *
    * \sa ir_variable_mode
    */
   unsigned mode:4;

   /**
    * Interpolation mode for shader inputs / outputs
    *
    * \sa ir_variable_interpolation
    */
   unsigned interpolation:2;

   /**
    * \name ARB_fragment_coord_conventions
    * @{
    */
   unsigned origin_upper_left:1;
   unsigned pixel_center_integer:1;
   /*@}*/

   /**
    * Was the location explicitly set in the shader?
    *
    * If the location is explicitly set in the shader, it \b cannot be changed
    * by the linker or by the API (e.g., calls to \c glBindAttribLocation have
    * no effect).
    */
   unsigned explicit_location:1;
   unsigned explicit_index:1;

   /**
    * Was an initial binding explicitly set in the shader?
    *
    * If so, constant_value contains an integer ir_constant representing the
    * initial binding point.
    */
   unsigned explicit_binding:1;

   /**
    * Does this variable have an initializer?
    *
    * This is used by the linker to cross-validiate initializers of global
    * variables.
    */
   unsigned has_initializer:1;

   /**
    * Is this variable a generic output or input that has not yet been matched
    * up to a variable in another stage of the pipeline?
    *
    * This is used by the linker as scratch storage while assigning locations
    * to generic inputs and outputs.
    */
   unsigned is_unmatched_generic_inout:1;

   /**
    * If non-zero, then this variable may be packed along with other variables
    * into a single varying slot, so this offset should be applied when
    * accessing components.  For example, an offset of 1 means that the x
    * component of this variable is actually stored in component y of the
    * location specified by \c location.
    */
   unsigned location_frac:2;

   /**
    * Non-zero if this variable was created by lowering a named interface
    * block which was not an array.
    *
    * Note that this variable and \c from_named_ifc_block_array will never
    * both be non-zero.
    */
   unsigned from_named_ifc_block_nonarray:1;

   /**
    * Non-zero if this variable was created by lowering a named interface
    * block which was an array.
    *
    * Note that this variable and \c from_named_ifc_block_nonarray will never
    * both be non-zero.
    */
   unsigned from_named_ifc_block_array:1;

   /**
    * \brief Layout qualifier for gl_FragDepth.
    *
    * This is not equal to \c ir_depth_layout_none if and only if this
    * variable is \c gl_FragDepth and a layout qualifier is specified.
    */
   ir_depth_layout depth_layout;

   /**
    * Storage location of the base of this variable
    *
    * The precise meaning of this field depends on the nature of the variable.
    *
    *   - Vertex shader input: one of the values from \c gl_vert_attrib.
    *   - Vertex shader output: one of the values from \c gl_varying_slot.
    *   - Geometry shader input: one of the values from \c gl_varying_slot.
    *   - Geometry shader output: one of the values from \c gl_varying_slot.
    *   - Fragment shader input: one of the values from \c gl_varying_slot.
    *   - Fragment shader output: one of the values from \c gl_frag_result.
    *   - Uniforms: Per-stage uniform slot number for default uniform block.
    *   - Uniforms: Index within the uniform block definition for UBO members.
    *   - Other: This field is not currently used.
    *
    * If the variable is a uniform, shader input, or shader output, and the
    * slot has not been assigned, the value will be -1.
    */
   int location;

   /**
    * output index for dual source blending.
    */
   int index;

   /**
    * Initial binding point for a sampler or UBO.
    *
    * For array types, this represents the binding point for the first element.
    */
   int binding;

   /**
    * Location an atomic counter is stored at.
    */
   struct {
      unsigned buffer_index;
      unsigned offset;
   } atomic;

   /**
    * Built-in state that backs this uniform
    *
    * Once set at variable creation, \c state_slots must remain invariant.
    * This is because, ideally, this array would be shared by all clones of
    * this variable in the IR tree.  In other words, we'd really like for it
    * to be a fly-weight.
    *
    * If the variable is not a uniform, \c num_state_slots will be zero and
    * \c state_slots will be \c NULL.
    */
   /*@{*/
   unsigned num_state_slots;    /**< Number of state slots used */
   ir_state_slot *state_slots;  /**< State descriptors. */
   /*@}*/

   /**
    * Emit a warning if this variable is accessed.
    */
   const char *warn_extension;

   /**
    * Value assigned in the initializer of a variable declared "const"
    */
   ir_constant *constant_value;

   /**
    * Constant expression assigned in the initializer of the variable
    *
    * \warning
    * This field and \c ::constant_value are distinct.  Even if the two fields
    * refer to constants with the same value, they must point to separate
    * objects.
    */
   ir_constant *constant_initializer;

private:
   /**
    * For variables that are in an interface block or are an instance of an
    * interface block, this is the \c GLSL_TYPE_INTERFACE type for that block.
    *
    * \sa ir_variable::location
    */
   const glsl_type *interface_type;
};

/**
 * A function that returns whether a built-in function is available in the
 * current shading language (based on version, ES or desktop, and extensions).
 */
typedef bool (*builtin_available_predicate)(const _mesa_glsl_parse_state *);

/*@{*/
/**
 * The representation of a function instance; may be the full definition or
 * simply a prototype.
 */
class ir_function_signature : public ir_instruction {
   /* An ir_function_signature will be part of the list of signatures in
    * an ir_function.
    */
public:
   ir_function_signature(const glsl_type *return_type,
                         builtin_available_predicate builtin_avail = NULL);

   virtual ir_function_signature *clone(void *mem_ctx,
					struct hash_table *ht) const;
   ir_function_signature *clone_prototype(void *mem_ctx,
					  struct hash_table *ht) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   /**
    * Attempt to evaluate this function as a constant expression,
    * given a list of the actual parameters and the variable context.
    * Returns NULL for non-built-ins.
    */
   ir_constant *constant_expression_value(exec_list *actual_parameters, struct hash_table *variable_context);

   /**
    * Get the name of the function for which this is a signature
    */
   const char *function_name() const;

   /**
    * Get a handle to the function for which this is a signature
    *
    * There is no setter function, this function returns a \c const pointer,
    * and \c ir_function_signature::_function is private for a reason.  The
    * only way to make a connection between a function and function signature
    * is via \c ir_function::add_signature.  This helps ensure that certain
    * invariants (i.e., a function signature is in the list of signatures for
    * its \c _function) are met.
    *
    * \sa ir_function::add_signature
    */
   inline const class ir_function *function() const
   {
      return this->_function;
   }

   /**
    * Check whether the qualifiers match between this signature's parameters
    * and the supplied parameter list.  If not, returns the name of the first
    * parameter with mismatched qualifiers (for use in error messages).
    */
   const char *qualifiers_match(exec_list *params);

   /**
    * Replace the current parameter list with the given one.  This is useful
    * if the current information came from a prototype, and either has invalid
    * or missing parameter names.
    */
   void replace_parameters(exec_list *new_params);

   /**
    * Function return type.
    *
    * \note This discards the optional precision qualifier.
    */
   const struct glsl_type *return_type;

   /**
    * List of ir_variable of function parameters.
    *
    * This represents the storage.  The paramaters passed in a particular
    * call will be in ir_call::actual_paramaters.
    */
   struct exec_list parameters;

   /** Whether or not this function has a body (which may be empty). */
   unsigned is_defined:1;

   /** Whether or not this function signature is a built-in. */
   bool is_builtin() const;

   /**
    * Whether or not this function is an intrinsic to be implemented
    * by the driver.
    */
   bool is_intrinsic;

   /** Whether or not a built-in is available for this shader. */
   bool is_builtin_available(const _mesa_glsl_parse_state *state) const;

   /** Body of instructions in the function. */
   struct exec_list body;

private:
   /**
    * A function pointer to a predicate that answers whether a built-in
    * function is available in the current shader.  NULL if not a built-in.
    */
   builtin_available_predicate builtin_avail;

   /** Function of which this signature is one overload. */
   class ir_function *_function;

   /** Function signature of which this one is a prototype clone */
   const ir_function_signature *origin;

   friend class ir_function;

   /**
    * Helper function to run a list of instructions for constant
    * expression evaluation.
    *
    * The hash table represents the values of the visible variables.
    * There are no scoping issues because the table is indexed on
    * ir_variable pointers, not variable names.
    *
    * Returns false if the expression is not constant, true otherwise,
    * and the value in *result if result is non-NULL.
    */
   bool constant_expression_evaluate_expression_list(const struct exec_list &body,
						     struct hash_table *variable_context,
						     ir_constant **result);
};


/**
 * Header for tracking multiple overloaded functions with the same name.
 * Contains a list of ir_function_signatures representing each of the
 * actual functions.
 */
class ir_function : public ir_instruction {
public:
   ir_function(const char *name);

   virtual ir_function *clone(void *mem_ctx, struct hash_table *ht) const;

   virtual ir_function *as_function()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   void add_signature(ir_function_signature *sig)
   {
      sig->_function = this;
      this->signatures.push_tail(sig);
   }

   /**
    * Get an iterator for the set of function signatures
    */
   exec_list_iterator iterator()
   {
      return signatures.iterator();
   }

   /**
    * Find a signature that matches a set of actual parameters, taking implicit
    * conversions into account.  Also flags whether the match was exact.
    */
   ir_function_signature *matching_signature(_mesa_glsl_parse_state *state,
                                             const exec_list *actual_param,
					     bool *match_is_exact);

   /**
    * Find a signature that matches a set of actual parameters, taking implicit
    * conversions into account.
    */
   ir_function_signature *matching_signature(_mesa_glsl_parse_state *state,
                                             const exec_list *actual_param);

   /**
    * Find a signature that exactly matches a set of actual parameters without
    * any implicit type conversions.
    */
   ir_function_signature *exact_matching_signature(_mesa_glsl_parse_state *state,
                                                   const exec_list *actual_ps);

   /**
    * Name of the function.
    */
   const char *name;

   /** Whether or not this function has a signature that isn't a built-in. */
   bool has_user_signature();

   /**
    * List of ir_function_signature for each overloaded function with this name.
    */
   struct exec_list signatures;
};

inline const char *ir_function_signature::function_name() const
{
   return this->_function->name;
}
/*@}*/


/**
 * IR instruction representing high-level if-statements
 */
class ir_if : public ir_instruction {
public:
   ir_if(ir_rvalue *condition)
      : condition(condition)
   {
      ir_type = ir_type_if;
   }

   virtual ir_if *clone(void *mem_ctx, struct hash_table *ht) const;

   virtual ir_if *as_if()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_rvalue *condition;
   /** List of ir_instruction for the body of the then branch */
   exec_list  then_instructions;
   /** List of ir_instruction for the body of the else branch */
   exec_list  else_instructions;
};


/**
 * IR instruction representing a high-level loop structure.
 */
class ir_loop : public ir_instruction {
public:
   ir_loop();

   virtual ir_loop *clone(void *mem_ctx, struct hash_table *ht) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   virtual ir_loop *as_loop()
   {
      return this;
   }

   /**
    * Get an iterator for the instructions of the loop body
    */
   exec_list_iterator iterator()
   {
      return body_instructions.iterator();
   }

   /** List of ir_instruction that make up the body of the loop. */
   exec_list body_instructions;

   /**
    * \name Loop counter and controls
    *
    * Represents a loop like a FORTRAN \c do-loop.
    *
    * \note
    * If \c from and \c to are the same value, the loop will execute once.
    */
   /*@{*/
   ir_rvalue *from;             /** Value of the loop counter on the first
				 * iteration of the loop.
				 */
   ir_rvalue *to;               /** Value of the loop counter on the last
				 * iteration of the loop.
				 */
   ir_rvalue *increment;
   ir_variable *counter;

   /**
    * Comparison operation in the loop terminator.
    *
    * If any of the loop control fields are non-\c NULL, this field must be
    * one of \c ir_binop_less, \c ir_binop_greater, \c ir_binop_lequal,
    * \c ir_binop_gequal, \c ir_binop_equal, or \c ir_binop_nequal.
    */
   int cmp;
   /*@}*/
};


class ir_assignment : public ir_instruction {
public:
   ir_assignment(ir_rvalue *lhs, ir_rvalue *rhs, ir_rvalue *condition = NULL);

   /**
    * Construct an assignment with an explicit write mask
    *
    * \note
    * Since a write mask is supplied, the LHS must already be a bare
    * \c ir_dereference.  The cannot be any swizzles in the LHS.
    */
   ir_assignment(ir_dereference *lhs, ir_rvalue *rhs, ir_rvalue *condition,
		 unsigned write_mask);

   virtual ir_assignment *clone(void *mem_ctx, struct hash_table *ht) const;

   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   virtual ir_assignment * as_assignment()
   {
      return this;
   }

   /**
    * Get a whole variable written by an assignment
    *
    * If the LHS of the assignment writes a whole variable, the variable is
    * returned.  Otherwise \c NULL is returned.  Examples of whole-variable
    * assignment are:
    *
    *  - Assigning to a scalar
    *  - Assigning to all components of a vector
    *  - Whole array (or matrix) assignment
    *  - Whole structure assignment
    */
   ir_variable *whole_variable_written();

   /**
    * Set the LHS of an assignment
    */
   void set_lhs(ir_rvalue *lhs);

   /**
    * Left-hand side of the assignment.
    *
    * This should be treated as read only.  If you need to set the LHS of an
    * assignment, use \c ir_assignment::set_lhs.
    */
   ir_dereference *lhs;

   /**
    * Value being assigned
    */
   ir_rvalue *rhs;

   /**
    * Optional condition for the assignment.
    */
   ir_rvalue *condition;


   /**
    * Component mask written
    *
    * For non-vector types in the LHS, this field will be zero.  For vector
    * types, a bit will be set for each component that is written.  Note that
    * for \c vec2 and \c vec3 types only the lower bits will ever be set.
    *
    * A partially-set write mask means that each enabled channel gets
    * the value from a consecutive channel of the rhs.  For example,
    * to write just .xyw of gl_FrontColor with color:
    *
    * (assign (constant bool (1)) (xyw)
    *     (var_ref gl_FragColor)
    *     (swiz xyw (var_ref color)))
    */
   unsigned write_mask:4;
};

/* Update ir_expression::get_num_operands() and operator_strs when
 * updating this list.
 */
enum ir_expression_operation {
   ir_unop_bit_not,
   ir_unop_logic_not,
   ir_unop_neg,
   ir_unop_abs,
   ir_unop_sign,
   ir_unop_rcp,
   ir_unop_rsq,
   ir_unop_sqrt,
   ir_unop_exp,         /**< Log base e on gentype */
   ir_unop_log,	        /**< Natural log on gentype */
   ir_unop_exp2,
   ir_unop_log2,
   ir_unop_f2i,         /**< Float-to-integer conversion. */
   ir_unop_f2u,         /**< Float-to-unsigned conversion. */
   ir_unop_i2f,         /**< Integer-to-float conversion. */
   ir_unop_f2b,         /**< Float-to-boolean conversion */
   ir_unop_b2f,         /**< Boolean-to-float conversion */
   ir_unop_i2b,         /**< int-to-boolean conversion */
   ir_unop_b2i,         /**< Boolean-to-int conversion */
   ir_unop_u2f,         /**< Unsigned-to-float conversion. */
   ir_unop_i2u,         /**< Integer-to-unsigned conversion. */
   ir_unop_u2i,         /**< Unsigned-to-integer conversion. */
   ir_unop_bitcast_i2f, /**< Bit-identical int-to-float "conversion" */
   ir_unop_bitcast_f2i, /**< Bit-identical float-to-int "conversion" */
   ir_unop_bitcast_u2f, /**< Bit-identical uint-to-float "conversion" */
   ir_unop_bitcast_f2u, /**< Bit-identical float-to-uint "conversion" */
   ir_unop_any,

   /**
    * \name Unary floating-point rounding operations.
    */
   /*@{*/
   ir_unop_trunc,
   ir_unop_ceil,
   ir_unop_floor,
   ir_unop_fract,
   ir_unop_round_even,
   /*@}*/

   /**
    * \name Trigonometric operations.
    */
   /*@{*/
   ir_unop_sin,
   ir_unop_cos,
   ir_unop_sin_reduced,    /**< Reduced range sin. [-pi, pi] */
   ir_unop_cos_reduced,    /**< Reduced range cos. [-pi, pi] */
   /*@}*/

   /**
    * \name Partial derivatives.
    */
   /*@{*/
   ir_unop_dFdx,
   ir_unop_dFdy,
   /*@}*/

   /**
    * \name Floating point pack and unpack operations.
    */
   /*@{*/
   ir_unop_pack_snorm_2x16,
   ir_unop_pack_snorm_4x8,
   ir_unop_pack_unorm_2x16,
   ir_unop_pack_unorm_4x8,
   ir_unop_pack_half_2x16,
   ir_unop_unpack_snorm_2x16,
   ir_unop_unpack_snorm_4x8,
   ir_unop_unpack_unorm_2x16,
   ir_unop_unpack_unorm_4x8,
   ir_unop_unpack_half_2x16,
   /*@}*/

   /**
    * \name Lowered floating point unpacking operations.
    *
    * \see lower_packing_builtins_visitor::split_unpack_half_2x16
    */
   /*@{*/
   ir_unop_unpack_half_2x16_split_x,
   ir_unop_unpack_half_2x16_split_y,
   /*@}*/

   /**
    * \name Bit operations, part of ARB_gpu_shader5.
    */
   /*@{*/
   ir_unop_bitfield_reverse,
   ir_unop_bit_count,
   ir_unop_find_msb,
   ir_unop_find_lsb,
   /*@}*/

   ir_unop_noise,

   /**
    * A sentinel marking the last of the unary operations.
    */
   ir_last_unop = ir_unop_noise,

   ir_binop_add,
   ir_binop_sub,
   ir_binop_mul,       /**< Floating-point or low 32-bit integer multiply. */
   ir_binop_imul_high, /**< Calculates the high 32-bits of a 64-bit multiply. */
   ir_binop_div,

   /**
    * Returns the carry resulting from the addition of the two arguments.
    */
   /*@{*/
   ir_binop_carry,
   /*@}*/

   /**
    * Returns the borrow resulting from the subtraction of the second argument
    * from the first argument.
    */
   /*@{*/
   ir_binop_borrow,
   /*@}*/

   /**
    * Takes one of two combinations of arguments:
    *
    * - mod(vecN, vecN)
    * - mod(vecN, float)
    *
    * Does not take integer types.
    */
   ir_binop_mod,

   /**
    * \name Binary comparison operators which return a boolean vector.
    * The type of both operands must be equal.
    */
   /*@{*/
   ir_binop_less,
   ir_binop_greater,
   ir_binop_lequal,
   ir_binop_gequal,
   ir_binop_equal,
   ir_binop_nequal,
   /**
    * Returns single boolean for whether all components of operands[0]
    * equal the components of operands[1].
    */
   ir_binop_all_equal,
   /**
    * Returns single boolean for whether any component of operands[0]
    * is not equal to the corresponding component of operands[1].
    */
   ir_binop_any_nequal,
   /*@}*/

   /**
    * \name Bit-wise binary operations.
    */
   /*@{*/
   ir_binop_lshift,
   ir_binop_rshift,
   ir_binop_bit_and,
   ir_binop_bit_xor,
   ir_binop_bit_or,
   /*@}*/

   ir_binop_logic_and,
   ir_binop_logic_xor,
   ir_binop_logic_or,

   ir_binop_dot,
   ir_binop_min,
   ir_binop_max,

   ir_binop_pow,

   /**
    * \name Lowered floating point packing operations.
    *
    * \see lower_packing_builtins_visitor::split_pack_half_2x16
    */
   /*@{*/
   ir_binop_pack_half_2x16_split,
   /*@}*/

   /**
    * \name First half of a lowered bitfieldInsert() operation.
    *
    * \see lower_instructions::bitfield_insert_to_bfm_bfi
    */
   /*@{*/
   ir_binop_bfm,
   /*@}*/

   /**
    * Load a value the size of a given GLSL type from a uniform block.
    *
    * operand0 is the ir_constant uniform block index in the linked shader.
    * operand1 is a byte offset within the uniform block.
    */
   ir_binop_ubo_load,

   /**
    * \name Multiplies a number by two to a power, part of ARB_gpu_shader5.
    */
   /*@{*/
   ir_binop_ldexp,
   /*@}*/

   /**
    * Extract a scalar from a vector
    *
    * operand0 is the vector
    * operand1 is the index of the field to read from operand0
    */
   ir_binop_vector_extract,

   /**
    * A sentinel marking the last of the binary operations.
    */
   ir_last_binop = ir_binop_vector_extract,

   /**
    * \name Fused floating-point multiply-add, part of ARB_gpu_shader5.
    */
   /*@{*/
   ir_triop_fma,
   /*@}*/

   ir_triop_lrp,

   /**
    * \name Conditional Select
    *
    * A vector conditional select instruction (like ?:, but operating per-
    * component on vectors).
    *
    * \see lower_instructions_visitor::ldexp_to_arith
    */
   /*@{*/
   ir_triop_csel,
   /*@}*/

   /**
    * \name Second half of a lowered bitfieldInsert() operation.
    *
    * \see lower_instructions::bitfield_insert_to_bfm_bfi
    */
   /*@{*/
   ir_triop_bfi,
   /*@}*/

   ir_triop_bitfield_extract,

   /**
    * Generate a value with one field of a vector changed
    *
    * operand0 is the vector
    * operand1 is the value to write into the vector result
    * operand2 is the index in operand0 to be modified
    */
   ir_triop_vector_insert,

   /**
    * A sentinel marking the last of the ternary operations.
    */
   ir_last_triop = ir_triop_vector_insert,

   ir_quadop_bitfield_insert,

   ir_quadop_vector,

   /**
    * A sentinel marking the last of the ternary operations.
    */
   ir_last_quadop = ir_quadop_vector,

   /**
    * A sentinel marking the last of all operations.
    */
   ir_last_opcode = ir_quadop_vector
};

class ir_expression : public ir_rvalue {
public:
   ir_expression(int op, const struct glsl_type *type,
                 ir_rvalue *op0, ir_rvalue *op1 = NULL,
                 ir_rvalue *op2 = NULL, ir_rvalue *op3 = NULL);

   /**
    * Constructor for unary operation expressions
    */
   ir_expression(int op, ir_rvalue *);

   /**
    * Constructor for binary operation expressions
    */
   ir_expression(int op, ir_rvalue *op0, ir_rvalue *op1);

   /**
    * Constructor for ternary operation expressions
    */
   ir_expression(int op, ir_rvalue *op0, ir_rvalue *op1, ir_rvalue *op2);

   virtual ir_expression *as_expression()
   {
      return this;
   }

   virtual bool equals(ir_instruction *ir);

   virtual ir_expression *clone(void *mem_ctx, struct hash_table *ht) const;

   /**
    * Attempt to constant-fold the expression
    *
    * The "variable_context" hash table links ir_variable * to ir_constant *
    * that represent the variables' values.  \c NULL represents an empty
    * context.
    *
    * If the expression cannot be constant folded, this method will return
    * \c NULL.
    */
   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   /**
    * Determine the number of operands used by an expression
    */
   static unsigned int get_num_operands(ir_expression_operation);

   /**
    * Determine the number of operands used by an expression
    */
   unsigned int get_num_operands() const
   {
      return (this->operation == ir_quadop_vector)
	 ? this->type->vector_elements : get_num_operands(operation);
   }

   /**
    * Return a string representing this expression's operator.
    */
   const char *operator_string();

   /**
    * Return a string representing this expression's operator.
    */
   static const char *operator_string(ir_expression_operation);


   /**
    * Do a reverse-lookup to translate the given string into an operator.
    */
   static ir_expression_operation get_operator(const char *);

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_expression_operation operation;
   ir_rvalue *operands[4];
};


/**
 * HIR instruction representing a high-level function call, containing a list
 * of parameters and returning a value in the supplied temporary.
 */
class ir_call : public ir_instruction {
public:
   ir_call(ir_function_signature *callee,
	   ir_dereference_variable *return_deref,
	   exec_list *actual_parameters)
      : return_deref(return_deref), callee(callee)
   {
      ir_type = ir_type_call;
      assert(callee->return_type != NULL);
      actual_parameters->move_nodes_to(& this->actual_parameters);
      this->use_builtin = callee->is_builtin();
   }

   virtual ir_call *clone(void *mem_ctx, struct hash_table *ht) const;

   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   virtual ir_call *as_call()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   /**
    * Get an iterator for the set of acutal parameters
    */
   exec_list_iterator iterator()
   {
      return actual_parameters.iterator();
   }

   /**
    * Get the name of the function being called.
    */
   const char *callee_name() const
   {
      return callee->function_name();
   }

   /**
    * Generates an inline version of the function before @ir,
    * storing the return value in return_deref.
    */
   void generate_inline(ir_instruction *ir);

   /**
    * Storage for the function's return value.
    * This must be NULL if the return type is void.
    */
   ir_dereference_variable *return_deref;

   /**
    * The specific function signature being called.
    */
   ir_function_signature *callee;

   /* List of ir_rvalue of paramaters passed in this call. */
   exec_list actual_parameters;

   /** Should this call only bind to a built-in function? */
   bool use_builtin;
};


/**
 * \name Jump-like IR instructions.
 *
 * These include \c break, \c continue, \c return, and \c discard.
 */
/*@{*/
class ir_jump : public ir_instruction {
protected:
   ir_jump()
   {
      ir_type = ir_type_unset;
   }

public:
   virtual ir_jump *as_jump()
   {
      return this;
   }
};

class ir_return : public ir_jump {
public:
   ir_return()
      : value(NULL)
   {
      this->ir_type = ir_type_return;
   }

   ir_return(ir_rvalue *value)
      : value(value)
   {
      this->ir_type = ir_type_return;
   }

   virtual ir_return *clone(void *mem_ctx, struct hash_table *) const;

   virtual ir_return *as_return()
   {
      return this;
   }

   ir_rvalue *get_value() const
   {
      return value;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_rvalue *value;
};


/**
 * Jump instructions used inside loops
 *
 * These include \c break and \c continue.  The \c break within a loop is
 * different from the \c break within a switch-statement.
 *
 * \sa ir_switch_jump
 */
class ir_loop_jump : public ir_jump {
public:
   enum jump_mode {
      jump_break,
      jump_continue
   };

   ir_loop_jump(jump_mode mode)
   {
      this->ir_type = ir_type_loop_jump;
      this->mode = mode;
   }

   virtual ir_loop_jump *clone(void *mem_ctx, struct hash_table *) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   bool is_break() const
   {
      return mode == jump_break;
   }

   bool is_continue() const
   {
      return mode == jump_continue;
   }

   /** Mode selector for the jump instruction. */
   enum jump_mode mode;
};

/**
 * IR instruction representing discard statements.
 */
class ir_discard : public ir_jump {
public:
   ir_discard()
   {
      this->ir_type = ir_type_discard;
      this->condition = NULL;
   }

   ir_discard(ir_rvalue *cond)
   {
      this->ir_type = ir_type_discard;
      this->condition = cond;
   }

   virtual ir_discard *clone(void *mem_ctx, struct hash_table *ht) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   virtual ir_discard *as_discard()
   {
      return this;
   }

   ir_rvalue *condition;
};
/*@}*/


/**
 * Texture sampling opcodes used in ir_texture
 */
enum ir_texture_opcode {
   ir_tex,		/**< Regular texture look-up */
   ir_txb,		/**< Texture look-up with LOD bias */
   ir_txl,		/**< Texture look-up with explicit LOD */
   ir_txd,		/**< Texture look-up with partial derivatvies */
   ir_txf,		/**< Texel fetch with explicit LOD */
   ir_txf_ms,           /**< Multisample texture fetch */
   ir_txs,		/**< Texture size */
   ir_lod,		/**< Texture lod query */
   ir_tg4,		/**< Texture gather */
   ir_query_levels      /**< Texture levels query */
};


/**
 * IR instruction to sample a texture
 *
 * The specific form of the IR instruction depends on the \c mode value
 * selected from \c ir_texture_opcodes.  In the printed IR, these will
 * appear as:
 *
 *                                    Texel offset (0 or an expression)
 *                                    | Projection divisor
 *                                    | |  Shadow comparitor
 *                                    | |  |
 *                                    v v  v
 * (tex <type> <sampler> <coordinate> 0 1 ( ))
 * (txb <type> <sampler> <coordinate> 0 1 ( ) <bias>)
 * (txl <type> <sampler> <coordinate> 0 1 ( ) <lod>)
 * (txd <type> <sampler> <coordinate> 0 1 ( ) (dPdx dPdy))
 * (txf <type> <sampler> <coordinate> 0       <lod>)
 * (txf_ms
 *      <type> <sampler> <coordinate>         <sample_index>)
 * (txs <type> <sampler> <lod>)
 * (lod <type> <sampler> <coordinate>)
 * (tg4 <type> <sampler> <coordinate> <offset> <component>)
 * (query_levels <type> <sampler>)
 */
class ir_texture : public ir_rvalue {
public:
   ir_texture(enum ir_texture_opcode op)
      : op(op), sampler(NULL), coordinate(NULL), projector(NULL),
        shadow_comparitor(NULL), offset(NULL)
   {
      this->ir_type = ir_type_texture;
      memset(&lod_info, 0, sizeof(lod_info));
   }

   virtual ir_texture *clone(void *mem_ctx, struct hash_table *) const;

   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_texture *as_texture()
   {
      return this;
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   virtual bool equals(ir_instruction *ir);

   /**
    * Return a string representing the ir_texture_opcode.
    */
   const char *opcode_string();

   /** Set the sampler and type. */
   void set_sampler(ir_dereference *sampler, const glsl_type *type);

   /**
    * Do a reverse-lookup to translate a string into an ir_texture_opcode.
    */
   static ir_texture_opcode get_opcode(const char *);

   enum ir_texture_opcode op;

   /** Sampler to use for the texture access. */
   ir_dereference *sampler;

   /** Texture coordinate to sample */
   ir_rvalue *coordinate;

   /**
    * Value used for projective divide.
    *
    * If there is no projective divide (the common case), this will be
    * \c NULL.  Optimization passes should check for this to point to a constant
    * of 1.0 and replace that with \c NULL.
    */
   ir_rvalue *projector;

   /**
    * Coordinate used for comparison on shadow look-ups.
    *
    * If there is no shadow comparison, this will be \c NULL.  For the
    * \c ir_txf opcode, this *must* be \c NULL.
    */
   ir_rvalue *shadow_comparitor;

   /** Texel offset. */
   ir_rvalue *offset;

   union {
      ir_rvalue *lod;		/**< Floating point LOD */
      ir_rvalue *bias;		/**< Floating point LOD bias */
      ir_rvalue *sample_index;  /**< MSAA sample index */
      ir_rvalue *component;     /**< Gather component selector */
      struct {
	 ir_rvalue *dPdx;	/**< Partial derivative of coordinate wrt X */
	 ir_rvalue *dPdy;	/**< Partial derivative of coordinate wrt Y */
      } grad;
   } lod_info;
};


struct ir_swizzle_mask {
   unsigned x:2;
   unsigned y:2;
   unsigned z:2;
   unsigned w:2;

   /**
    * Number of components in the swizzle.
    */
   unsigned num_components:3;

   /**
    * Does the swizzle contain duplicate components?
    *
    * L-value swizzles cannot contain duplicate components.
    */
   unsigned has_duplicates:1;
};


class ir_swizzle : public ir_rvalue {
public:
   ir_swizzle(ir_rvalue *, unsigned x, unsigned y, unsigned z, unsigned w,
              unsigned count);

   ir_swizzle(ir_rvalue *val, const unsigned *components, unsigned count);

   ir_swizzle(ir_rvalue *val, ir_swizzle_mask mask);

   virtual ir_swizzle *clone(void *mem_ctx, struct hash_table *) const;

   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   virtual ir_swizzle *as_swizzle()
   {
      return this;
   }

   /**
    * Construct an ir_swizzle from the textual representation.  Can fail.
    */
   static ir_swizzle *create(ir_rvalue *, const char *, unsigned vector_length);

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   virtual bool equals(ir_instruction *ir);

   bool is_lvalue() const
   {
      return val->is_lvalue() && !mask.has_duplicates;
   }

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced() const;

   ir_rvalue *val;
   ir_swizzle_mask mask;

private:
   /**
    * Initialize the mask component of a swizzle
    *
    * This is used by the \c ir_swizzle constructors.
    */
   void init_mask(const unsigned *components, unsigned count);
};


class ir_dereference : public ir_rvalue {
public:
   virtual ir_dereference *clone(void *mem_ctx, struct hash_table *) const = 0;

   virtual ir_dereference *as_dereference()
   {
      return this;
   }

   bool is_lvalue() const;

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced() const = 0;

   /**
    * Get the constant that is ultimately referenced by an r-value,
    * in a constant expression evaluation context.
    *
    * The offset is used when the reference is to a specific column of
    * a matrix.
    */
  virtual void constant_referenced(struct hash_table *variable_context, ir_constant *&store, int &offset) const = 0;
};


class ir_dereference_variable : public ir_dereference {
public:
   ir_dereference_variable(ir_variable *var);

   virtual ir_dereference_variable *clone(void *mem_ctx,
					  struct hash_table *) const;

   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   virtual ir_dereference_variable *as_dereference_variable()
   {
      return this;
   }

   virtual bool equals(ir_instruction *ir);

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced() const
   {
      return this->var;
   }

   /**
    * Get the constant that is ultimately referenced by an r-value,
    * in a constant expression evaluation context.
    *
    * The offset is used when the reference is to a specific column of
    * a matrix.
    */
   virtual void constant_referenced(struct hash_table *variable_context, ir_constant *&store, int &offset) const;

   virtual ir_variable *whole_variable_referenced()
   {
      /* ir_dereference_variable objects always dereference the entire
       * variable.  However, if this dereference is dereferenced by anything
       * else, the complete deferefernce chain is not a whole-variable
       * dereference.  This method should only be called on the top most
       * ir_rvalue in a dereference chain.
       */
      return this->var;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   /**
    * Object being dereferenced.
    */
   ir_variable *var;
};


class ir_dereference_array : public ir_dereference {
public:
   ir_dereference_array(ir_rvalue *value, ir_rvalue *array_index);

   ir_dereference_array(ir_variable *var, ir_rvalue *array_index);

   virtual ir_dereference_array *clone(void *mem_ctx,
				       struct hash_table *) const;

   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   virtual ir_dereference_array *as_dereference_array()
   {
      return this;
   }

   virtual bool equals(ir_instruction *ir);

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced() const
   {
      return this->array->variable_referenced();
   }

   /**
    * Get the constant that is ultimately referenced by an r-value,
    * in a constant expression evaluation context.
    *
    * The offset is used when the reference is to a specific column of
    * a matrix.
    */
   virtual void constant_referenced(struct hash_table *variable_context, ir_constant *&store, int &offset) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_rvalue *array;
   ir_rvalue *array_index;

private:
   void set_array(ir_rvalue *value);
};


class ir_dereference_record : public ir_dereference {
public:
   ir_dereference_record(ir_rvalue *value, const char *field);

   ir_dereference_record(ir_variable *var, const char *field);

   virtual ir_dereference_record *clone(void *mem_ctx,
					struct hash_table *) const;

   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   virtual ir_dereference_record *as_dereference_record()
   {
      return this;
   }

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced() const
   {
      return this->record->variable_referenced();
   }

   /**
    * Get the constant that is ultimately referenced by an r-value,
    * in a constant expression evaluation context.
    *
    * The offset is used when the reference is to a specific column of
    * a matrix.
    */
   virtual void constant_referenced(struct hash_table *variable_context, ir_constant *&store, int &offset) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_rvalue *record;
   const char *field;
};


/**
 * Data stored in an ir_constant
 */
union ir_constant_data {
      unsigned u[16];
      int i[16];
      float f[16];
      bool b[16];
};


class ir_constant : public ir_rvalue {
public:
   ir_constant(const struct glsl_type *type, const ir_constant_data *data);
   ir_constant(bool b, unsigned vector_elements=1);
   ir_constant(unsigned int u, unsigned vector_elements=1);
   ir_constant(int i, unsigned vector_elements=1);
   ir_constant(float f, unsigned vector_elements=1);

   /**
    * Construct an ir_constant from a list of ir_constant values
    */
   ir_constant(const struct glsl_type *type, exec_list *values);

   /**
    * Construct an ir_constant from a scalar component of another ir_constant
    *
    * The new \c ir_constant inherits the type of the component from the
    * source constant.
    *
    * \note
    * In the case of a matrix constant, the new constant is a scalar, \b not
    * a vector.
    */
   ir_constant(const ir_constant *c, unsigned i);

   /**
    * Return a new ir_constant of the specified type containing all zeros.
    */
   static ir_constant *zero(void *mem_ctx, const glsl_type *type);

   virtual ir_constant *clone(void *mem_ctx, struct hash_table *) const;

   virtual ir_constant *constant_expression_value(struct hash_table *variable_context = NULL);

   virtual ir_constant *as_constant()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   virtual bool equals(ir_instruction *ir);

   /**
    * Get a particular component of a constant as a specific type
    *
    * This is useful, for example, to get a value from an integer constant
    * as a float or bool.  This appears frequently when constructors are
    * called with all constant parameters.
    */
   /*@{*/
   bool get_bool_component(unsigned i) const;
   float get_float_component(unsigned i) const;
   int get_int_component(unsigned i) const;
   unsigned get_uint_component(unsigned i) const;
   /*@}*/

   ir_constant *get_array_element(unsigned i) const;

   ir_constant *get_record_field(const char *name);

   /**
    * Copy the values on another constant at a given offset.
    *
    * The offset is ignored for array or struct copies, it's only for
    * scalars or vectors into vectors or matrices.
    *
    * With identical types on both sides and zero offset it's clone()
    * without creating a new object.
    */

   void copy_offset(ir_constant *src, int offset);

   /**
    * Copy the values on another constant at a given offset and
    * following an assign-like mask.
    *
    * The mask is ignored for scalars.
    *
    * Note that this function only handles what assign can handle,
    * i.e. at most a vector as source and a column of a matrix as
    * destination.
    */

   void copy_masked_offset(ir_constant *src, int offset, unsigned int mask);

   /**
    * Determine whether a constant has the same value as another constant
    *
    * \sa ir_constant::is_zero, ir_constant::is_one,
    * ir_constant::is_negative_one, ir_constant::is_basis
    */
   bool has_value(const ir_constant *) const;

   virtual bool is_zero() const;
   virtual bool is_one() const;
   virtual bool is_negative_one() const;
   virtual bool is_basis() const;

   /**
    * Value of the constant.
    *
    * The field used to back the values supplied by the constant is determined
    * by the type associated with the \c ir_instruction.  Constants may be
    * scalars, vectors, or matrices.
    */
   union ir_constant_data value;

   /* Array elements */
   ir_constant **array_elements;

   /* Structure fields */
   exec_list components;

private:
   /**
    * Parameterless constructor only used by the clone method
    */
   ir_constant(void);
};

/*@}*/

/**
 * IR instruction to emit a vertex in a geometry shader.
 */
class ir_emit_vertex : public ir_instruction {
public:
   ir_emit_vertex()
   {
      ir_type = ir_type_emit_vertex;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_emit_vertex *clone(void *mem_ctx, struct hash_table *) const
   {
      return new(mem_ctx) ir_emit_vertex();
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
};

/**
 * IR instruction to complete the current primitive and start a new one in a
 * geometry shader.
 */
class ir_end_primitive : public ir_instruction {
public:
   ir_end_primitive()
   {
      ir_type = ir_type_end_primitive;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_end_primitive *clone(void *mem_ctx, struct hash_table *) const
   {
      return new(mem_ctx) ir_end_primitive();
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
};

/**
 * Apply a visitor to each IR node in a list
 */
void
visit_exec_list(exec_list *list, ir_visitor *visitor);

/**
 * Validate invariants on each IR node in a list
 */
void validate_ir_tree(exec_list *instructions);

struct _mesa_glsl_parse_state;
struct gl_shader_program;

/**
 * Detect whether an unlinked shader contains static recursion
 *
 * If the list of instructions is determined to contain static recursion,
 * \c _mesa_glsl_error will be called to emit error messages for each function
 * that is in the recursion cycle.
 */
void
detect_recursion_unlinked(struct _mesa_glsl_parse_state *state,
			  exec_list *instructions);

/**
 * Detect whether a linked shader contains static recursion
 *
 * If the list of instructions is determined to contain static recursion,
 * \c link_error_printf will be called to emit error messages for each function
 * that is in the recursion cycle.  In addition,
 * \c gl_shader_program::LinkStatus will be set to false.
 */
void
detect_recursion_linked(struct gl_shader_program *prog,
			exec_list *instructions);

/**
 * Make a clone of each IR instruction in a list
 *
 * \param in   List of IR instructions that are to be cloned
 * \param out  List to hold the cloned instructions
 */
void
clone_ir_list(void *mem_ctx, exec_list *out, const exec_list *in);

extern void
_mesa_glsl_initialize_variables(exec_list *instructions,
				struct _mesa_glsl_parse_state *state);

extern void
_mesa_glsl_initialize_functions(_mesa_glsl_parse_state *state);

extern void
_mesa_glsl_initialize_builtin_functions();

extern ir_function_signature *
_mesa_glsl_find_builtin_function(_mesa_glsl_parse_state *state,
                                 const char *name, exec_list *actual_parameters);

extern void
_mesa_glsl_release_functions(void);

extern void
_mesa_glsl_release_builtin_functions(void);

extern void
reparent_ir(exec_list *list, void *mem_ctx);

struct glsl_symbol_table;

extern void
import_prototypes(const exec_list *source, exec_list *dest,
		  struct glsl_symbol_table *symbols, void *mem_ctx);

extern bool
ir_has_call(ir_instruction *ir);

extern void
do_set_program_inouts(exec_list *instructions, struct gl_program *prog,
                      GLenum shader_type);

extern char *
prototype_string(const glsl_type *return_type, const char *name,
		 exec_list *parameters);

const char *
mode_string(const ir_variable *var);

extern "C" {
#endif /* __cplusplus */

extern void _mesa_print_ir(struct exec_list *instructions,
                           struct _mesa_glsl_parse_state *state);

#ifdef __cplusplus
} /* extern "C" */
#endif

unsigned
vertices_per_prim(GLenum prim);

#endif /* IR_H */