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
|
/*
** Lua parser (source code -> bytecode).
** Copyright (C) 2005-2014 Mike Pall. See Copyright Notice in luajit.h
**
** Major portions taken verbatim or adapted from the Lua interpreter.
** Copyright (C) 1994-2008 Lua.org, PUC-Rio. See Copyright Notice in lua.h
*/
#define lj_parse_c
#define LUA_CORE
#include "lj_obj.h"
#include "lj_gc.h"
#include "lj_err.h"
#include "lj_debug.h"
#include "lj_str.h"
#include "lj_tab.h"
#include "lj_func.h"
#include "lj_state.h"
#include "lj_bc.h"
#if LJ_HASFFI
#include "lj_ctype.h"
#endif
#include "lj_lex.h"
#include "lj_parse.h"
#include "lj_vm.h"
#include "lj_vmevent.h"
/* -- Parser structures and definitions ----------------------------------- */
/* Expression kinds. */
typedef enum {
/* Constant expressions must be first and in this order: */
VKNIL,
VKFALSE,
VKTRUE,
VKSTR, /* sval = string value */
VKNUM, /* nval = number value */
VKLAST = VKNUM,
VKCDATA, /* nval = cdata value, not treated as a constant expression */
/* Non-constant expressions follow: */
VLOCAL, /* info = local register, aux = vstack index */
VUPVAL, /* info = upvalue index, aux = vstack index */
VGLOBAL, /* sval = string value */
VINDEXED, /* info = table register, aux = index reg/byte/string const */
VJMP, /* info = instruction PC */
VRELOCABLE, /* info = instruction PC */
VNONRELOC, /* info = result register */
VCALL, /* info = instruction PC, aux = base */
VVOID
} ExpKind;
/* Expression descriptor. */
typedef struct ExpDesc {
union {
struct {
uint32_t info; /* Primary info. */
uint32_t aux; /* Secondary info. */
} s;
TValue nval; /* Number value. */
GCstr *sval; /* String value. */
} u;
ExpKind k;
BCPos t; /* True condition jump list. */
BCPos f; /* False condition jump list. */
} ExpDesc;
/* Macros for expressions. */
#define expr_hasjump(e) ((e)->t != (e)->f)
#define expr_isk(e) ((e)->k <= VKLAST)
#define expr_isk_nojump(e) (expr_isk(e) && !expr_hasjump(e))
#define expr_isnumk(e) ((e)->k == VKNUM)
#define expr_isnumk_nojump(e) (expr_isnumk(e) && !expr_hasjump(e))
#define expr_isstrk(e) ((e)->k == VKSTR)
#define expr_numtv(e) check_exp(expr_isnumk((e)), &(e)->u.nval)
#define expr_numberV(e) numberVnum(expr_numtv((e)))
/* Initialize expression. */
static LJ_AINLINE void expr_init(ExpDesc *e, ExpKind k, uint32_t info)
{
e->k = k;
e->u.s.info = info;
e->f = e->t = NO_JMP;
}
/* Check number constant for +-0. */
static int expr_numiszero(ExpDesc *e)
{
TValue *o = expr_numtv(e);
return tvisint(o) ? (intV(o) == 0) : tviszero(o);
}
/* Per-function linked list of scope blocks. */
typedef struct FuncScope {
struct FuncScope *prev; /* Link to outer scope. */
MSize vstart; /* Start of block-local variables. */
uint8_t nactvar; /* Number of active vars outside the scope. */
uint8_t flags; /* Scope flags. */
} FuncScope;
#define FSCOPE_LOOP 0x01 /* Scope is a (breakable) loop. */
#define FSCOPE_BREAK 0x02 /* Break used in scope. */
#define FSCOPE_GOLA 0x04 /* Goto or label used in scope. */
#define FSCOPE_UPVAL 0x08 /* Upvalue in scope. */
#define FSCOPE_NOCLOSE 0x10 /* Do not close upvalues. */
#define NAME_BREAK ((GCstr *)(uintptr_t)1)
/* Index into variable stack. */
typedef uint16_t VarIndex;
#define LJ_MAX_VSTACK (65536 - LJ_MAX_UPVAL)
/* Variable/goto/label info. */
#define VSTACK_VAR_RW 0x01 /* R/W variable. */
#define VSTACK_GOTO 0x02 /* Pending goto. */
#define VSTACK_LABEL 0x04 /* Label. */
/* Per-function state. */
typedef struct FuncState {
GCtab *kt; /* Hash table for constants. */
LexState *ls; /* Lexer state. */
lua_State *L; /* Lua state. */
FuncScope *bl; /* Current scope. */
struct FuncState *prev; /* Enclosing function. */
BCPos pc; /* Next bytecode position. */
BCPos lasttarget; /* Bytecode position of last jump target. */
BCPos jpc; /* Pending jump list to next bytecode. */
BCReg freereg; /* First free register. */
BCReg nactvar; /* Number of active local variables. */
BCReg nkn, nkgc; /* Number of lua_Number/GCobj constants */
BCLine linedefined; /* First line of the function definition. */
BCInsLine *bcbase; /* Base of bytecode stack. */
BCPos bclim; /* Limit of bytecode stack. */
MSize vbase; /* Base of variable stack for this function. */
uint8_t flags; /* Prototype flags. */
uint8_t numparams; /* Number of parameters. */
uint8_t framesize; /* Fixed frame size. */
uint8_t nuv; /* Number of upvalues */
VarIndex varmap[LJ_MAX_LOCVAR]; /* Map from register to variable idx. */
VarIndex uvmap[LJ_MAX_UPVAL]; /* Map from upvalue to variable idx. */
VarIndex uvtmp[LJ_MAX_UPVAL]; /* Temporary upvalue map. */
} FuncState;
/* Binary and unary operators. ORDER OPR */
typedef enum BinOpr {
OPR_ADD, OPR_SUB, OPR_MUL, OPR_DIV, OPR_MOD, OPR_POW, /* ORDER ARITH */
OPR_CONCAT,
OPR_NE, OPR_EQ,
OPR_LT, OPR_GE, OPR_LE, OPR_GT,
OPR_AND, OPR_OR,
OPR_NOBINOPR
} BinOpr;
LJ_STATIC_ASSERT((int)BC_ISGE-(int)BC_ISLT == (int)OPR_GE-(int)OPR_LT);
LJ_STATIC_ASSERT((int)BC_ISLE-(int)BC_ISLT == (int)OPR_LE-(int)OPR_LT);
LJ_STATIC_ASSERT((int)BC_ISGT-(int)BC_ISLT == (int)OPR_GT-(int)OPR_LT);
LJ_STATIC_ASSERT((int)BC_SUBVV-(int)BC_ADDVV == (int)OPR_SUB-(int)OPR_ADD);
LJ_STATIC_ASSERT((int)BC_MULVV-(int)BC_ADDVV == (int)OPR_MUL-(int)OPR_ADD);
LJ_STATIC_ASSERT((int)BC_DIVVV-(int)BC_ADDVV == (int)OPR_DIV-(int)OPR_ADD);
LJ_STATIC_ASSERT((int)BC_MODVV-(int)BC_ADDVV == (int)OPR_MOD-(int)OPR_ADD);
/* -- Error handling ------------------------------------------------------ */
LJ_NORET LJ_NOINLINE static void err_syntax(LexState *ls, ErrMsg em)
{
lj_lex_error(ls, ls->token, em);
}
LJ_NORET LJ_NOINLINE static void err_token(LexState *ls, LexToken token)
{
lj_lex_error(ls, ls->token, LJ_ERR_XTOKEN, lj_lex_token2str(ls, token));
}
LJ_NORET static void err_limit(FuncState *fs, uint32_t limit, const char *what)
{
if (fs->linedefined == 0)
lj_lex_error(fs->ls, 0, LJ_ERR_XLIMM, limit, what);
else
lj_lex_error(fs->ls, 0, LJ_ERR_XLIMF, fs->linedefined, limit, what);
}
#define checklimit(fs, v, l, m) if ((v) >= (l)) err_limit(fs, l, m)
#define checklimitgt(fs, v, l, m) if ((v) > (l)) err_limit(fs, l, m)
#define checkcond(ls, c, em) { if (!(c)) err_syntax(ls, em); }
/* -- Management of constants --------------------------------------------- */
/* Return bytecode encoding for primitive constant. */
#define const_pri(e) check_exp((e)->k <= VKTRUE, (e)->k)
#define tvhaskslot(o) ((o)->u32.hi == 0)
#define tvkslot(o) ((o)->u32.lo)
/* Add a number constant. */
static BCReg const_num(FuncState *fs, ExpDesc *e)
{
lua_State *L = fs->L;
TValue *o;
lua_assert(expr_isnumk(e));
o = lj_tab_set(L, fs->kt, &e->u.nval);
if (tvhaskslot(o))
return tvkslot(o);
o->u64 = fs->nkn;
return fs->nkn++;
}
/* Add a GC object constant. */
static BCReg const_gc(FuncState *fs, GCobj *gc, uint32_t itype)
{
lua_State *L = fs->L;
TValue key, *o;
setgcV(L, &key, gc, itype);
/* NOBARRIER: the key is new or kept alive. */
o = lj_tab_set(L, fs->kt, &key);
if (tvhaskslot(o))
return tvkslot(o);
o->u64 = fs->nkgc;
return fs->nkgc++;
}
/* Add a string constant. */
static BCReg const_str(FuncState *fs, ExpDesc *e)
{
lua_assert(expr_isstrk(e) || e->k == VGLOBAL);
return const_gc(fs, obj2gco(e->u.sval), LJ_TSTR);
}
/* Anchor string constant to avoid GC. */
GCstr *lj_parse_keepstr(LexState *ls, const char *str, size_t len)
{
/* NOBARRIER: the key is new or kept alive. */
lua_State *L = ls->L;
GCstr *s = lj_str_new(L, str, len);
TValue *tv = lj_tab_setstr(L, ls->fs->kt, s);
if (tvisnil(tv)) setboolV(tv, 1);
lj_gc_check(L);
return s;
}
#if LJ_HASFFI
/* Anchor cdata to avoid GC. */
void lj_parse_keepcdata(LexState *ls, TValue *tv, GCcdata *cd)
{
/* NOBARRIER: the key is new or kept alive. */
lua_State *L = ls->L;
setcdataV(L, tv, cd);
setboolV(lj_tab_set(L, ls->fs->kt, tv), 1);
}
#endif
/* -- Jump list handling -------------------------------------------------- */
/* Get next element in jump list. */
static BCPos jmp_next(FuncState *fs, BCPos pc)
{
ptrdiff_t delta = bc_j(fs->bcbase[pc].ins);
if ((BCPos)delta == NO_JMP)
return NO_JMP;
else
return (BCPos)(((ptrdiff_t)pc+1)+delta);
}
/* Check if any of the instructions on the jump list produce no value. */
static int jmp_novalue(FuncState *fs, BCPos list)
{
for (; list != NO_JMP; list = jmp_next(fs, list)) {
BCIns p = fs->bcbase[list >= 1 ? list-1 : list].ins;
if (!(bc_op(p) == BC_ISTC || bc_op(p) == BC_ISFC || bc_a(p) == NO_REG))
return 1;
}
return 0;
}
/* Patch register of test instructions. */
static int jmp_patchtestreg(FuncState *fs, BCPos pc, BCReg reg)
{
BCInsLine *ilp = &fs->bcbase[pc >= 1 ? pc-1 : pc];
BCOp op = bc_op(ilp->ins);
if (op == BC_ISTC || op == BC_ISFC) {
if (reg != NO_REG && reg != bc_d(ilp->ins)) {
setbc_a(&ilp->ins, reg);
} else { /* Nothing to store or already in the right register. */
setbc_op(&ilp->ins, op+(BC_IST-BC_ISTC));
setbc_a(&ilp->ins, 0);
}
} else if (bc_a(ilp->ins) == NO_REG) {
if (reg == NO_REG) {
ilp->ins = BCINS_AJ(BC_JMP, bc_a(fs->bcbase[pc].ins), 0);
} else {
setbc_a(&ilp->ins, reg);
if (reg >= bc_a(ilp[1].ins))
setbc_a(&ilp[1].ins, reg+1);
}
} else {
return 0; /* Cannot patch other instructions. */
}
return 1;
}
/* Drop values for all instructions on jump list. */
static void jmp_dropval(FuncState *fs, BCPos list)
{
for (; list != NO_JMP; list = jmp_next(fs, list))
jmp_patchtestreg(fs, list, NO_REG);
}
/* Patch jump instruction to target. */
static void jmp_patchins(FuncState *fs, BCPos pc, BCPos dest)
{
BCIns *jmp = &fs->bcbase[pc].ins;
BCPos offset = dest-(pc+1)+BCBIAS_J;
lua_assert(dest != NO_JMP);
if (offset > BCMAX_D)
err_syntax(fs->ls, LJ_ERR_XJUMP);
setbc_d(jmp, offset);
}
/* Append to jump list. */
static void jmp_append(FuncState *fs, BCPos *l1, BCPos l2)
{
if (l2 == NO_JMP) {
return;
} else if (*l1 == NO_JMP) {
*l1 = l2;
} else {
BCPos list = *l1;
BCPos next;
while ((next = jmp_next(fs, list)) != NO_JMP) /* Find last element. */
list = next;
jmp_patchins(fs, list, l2);
}
}
/* Patch jump list and preserve produced values. */
static void jmp_patchval(FuncState *fs, BCPos list, BCPos vtarget,
BCReg reg, BCPos dtarget)
{
while (list != NO_JMP) {
BCPos next = jmp_next(fs, list);
if (jmp_patchtestreg(fs, list, reg))
jmp_patchins(fs, list, vtarget); /* Jump to target with value. */
else
jmp_patchins(fs, list, dtarget); /* Jump to default target. */
list = next;
}
}
/* Jump to following instruction. Append to list of pending jumps. */
static void jmp_tohere(FuncState *fs, BCPos list)
{
fs->lasttarget = fs->pc;
jmp_append(fs, &fs->jpc, list);
}
/* Patch jump list to target. */
static void jmp_patch(FuncState *fs, BCPos list, BCPos target)
{
if (target == fs->pc) {
jmp_tohere(fs, list);
} else {
lua_assert(target < fs->pc);
jmp_patchval(fs, list, target, NO_REG, target);
}
}
/* -- Bytecode register allocator ----------------------------------------- */
/* Bump frame size. */
static void bcreg_bump(FuncState *fs, BCReg n)
{
BCReg sz = fs->freereg + n;
if (sz > fs->framesize) {
if (sz >= LJ_MAX_SLOTS)
err_syntax(fs->ls, LJ_ERR_XSLOTS);
fs->framesize = (uint8_t)sz;
}
}
/* Reserve registers. */
static void bcreg_reserve(FuncState *fs, BCReg n)
{
bcreg_bump(fs, n);
fs->freereg += n;
}
/* Free register. */
static void bcreg_free(FuncState *fs, BCReg reg)
{
if (reg >= fs->nactvar) {
fs->freereg--;
lua_assert(reg == fs->freereg);
}
}
/* Free register for expression. */
static void expr_free(FuncState *fs, ExpDesc *e)
{
if (e->k == VNONRELOC)
bcreg_free(fs, e->u.s.info);
}
/* -- Bytecode emitter ---------------------------------------------------- */
/* Emit bytecode instruction. */
static BCPos bcemit_INS(FuncState *fs, BCIns ins)
{
BCPos pc = fs->pc;
LexState *ls = fs->ls;
jmp_patchval(fs, fs->jpc, pc, NO_REG, pc);
fs->jpc = NO_JMP;
if (LJ_UNLIKELY(pc >= fs->bclim)) {
ptrdiff_t base = fs->bcbase - ls->bcstack;
checklimit(fs, ls->sizebcstack, LJ_MAX_BCINS, "bytecode instructions");
lj_mem_growvec(fs->L, ls->bcstack, ls->sizebcstack, LJ_MAX_BCINS,BCInsLine);
fs->bclim = (BCPos)(ls->sizebcstack - base);
fs->bcbase = ls->bcstack + base;
}
fs->bcbase[pc].ins = ins;
fs->bcbase[pc].line = ls->lastline;
fs->pc = pc+1;
return pc;
}
#define bcemit_ABC(fs, o, a, b, c) bcemit_INS(fs, BCINS_ABC(o, a, b, c))
#define bcemit_AD(fs, o, a, d) bcemit_INS(fs, BCINS_AD(o, a, d))
#define bcemit_AJ(fs, o, a, j) bcemit_INS(fs, BCINS_AJ(o, a, j))
#define bcptr(fs, e) (&(fs)->bcbase[(e)->u.s.info].ins)
/* -- Bytecode emitter for expressions ------------------------------------ */
/* Discharge non-constant expression to any register. */
static void expr_discharge(FuncState *fs, ExpDesc *e)
{
BCIns ins;
if (e->k == VUPVAL) {
ins = BCINS_AD(BC_UGET, 0, e->u.s.info);
} else if (e->k == VGLOBAL) {
ins = BCINS_AD(BC_GGET, 0, const_str(fs, e));
} else if (e->k == VINDEXED) {
BCReg rc = e->u.s.aux;
if ((int32_t)rc < 0) {
ins = BCINS_ABC(BC_TGETS, 0, e->u.s.info, ~rc);
} else if (rc > BCMAX_C) {
ins = BCINS_ABC(BC_TGETB, 0, e->u.s.info, rc-(BCMAX_C+1));
} else {
bcreg_free(fs, rc);
ins = BCINS_ABC(BC_TGETV, 0, e->u.s.info, rc);
}
bcreg_free(fs, e->u.s.info);
} else if (e->k == VCALL) {
e->u.s.info = e->u.s.aux;
e->k = VNONRELOC;
return;
} else if (e->k == VLOCAL) {
e->k = VNONRELOC;
return;
} else {
return;
}
e->u.s.info = bcemit_INS(fs, ins);
e->k = VRELOCABLE;
}
/* Emit bytecode to set a range of registers to nil. */
static void bcemit_nil(FuncState *fs, BCReg from, BCReg n)
{
if (fs->pc > fs->lasttarget) { /* No jumps to current position? */
BCIns *ip = &fs->bcbase[fs->pc-1].ins;
BCReg pto, pfrom = bc_a(*ip);
switch (bc_op(*ip)) { /* Try to merge with the previous instruction. */
case BC_KPRI:
if (bc_d(*ip) != ~LJ_TNIL) break;
if (from == pfrom) {
if (n == 1) return;
} else if (from == pfrom+1) {
from = pfrom;
n++;
} else {
break;
}
*ip = BCINS_AD(BC_KNIL, from, from+n-1); /* Replace KPRI. */
return;
case BC_KNIL:
pto = bc_d(*ip);
if (pfrom <= from && from <= pto+1) { /* Can we connect both ranges? */
if (from+n-1 > pto)
setbc_d(ip, from+n-1); /* Patch previous instruction range. */
return;
}
break;
default:
break;
}
}
/* Emit new instruction or replace old instruction. */
bcemit_INS(fs, n == 1 ? BCINS_AD(BC_KPRI, from, VKNIL) :
BCINS_AD(BC_KNIL, from, from+n-1));
}
/* Discharge an expression to a specific register. Ignore branches. */
static void expr_toreg_nobranch(FuncState *fs, ExpDesc *e, BCReg reg)
{
BCIns ins;
expr_discharge(fs, e);
if (e->k == VKSTR) {
ins = BCINS_AD(BC_KSTR, reg, const_str(fs, e));
} else if (e->k == VKNUM) {
#if LJ_DUALNUM
cTValue *tv = expr_numtv(e);
if (tvisint(tv) && checki16(intV(tv)))
ins = BCINS_AD(BC_KSHORT, reg, (BCReg)(uint16_t)intV(tv));
else
#else
lua_Number n = expr_numberV(e);
int32_t k = lj_num2int(n);
if (checki16(k) && n == (lua_Number)k)
ins = BCINS_AD(BC_KSHORT, reg, (BCReg)(uint16_t)k);
else
#endif
ins = BCINS_AD(BC_KNUM, reg, const_num(fs, e));
#if LJ_HASFFI
} else if (e->k == VKCDATA) {
fs->flags |= PROTO_FFI;
ins = BCINS_AD(BC_KCDATA, reg,
const_gc(fs, obj2gco(cdataV(&e->u.nval)), LJ_TCDATA));
#endif
} else if (e->k == VRELOCABLE) {
setbc_a(bcptr(fs, e), reg);
goto noins;
} else if (e->k == VNONRELOC) {
if (reg == e->u.s.info)
goto noins;
ins = BCINS_AD(BC_MOV, reg, e->u.s.info);
} else if (e->k == VKNIL) {
bcemit_nil(fs, reg, 1);
goto noins;
} else if (e->k <= VKTRUE) {
ins = BCINS_AD(BC_KPRI, reg, const_pri(e));
} else {
lua_assert(e->k == VVOID || e->k == VJMP);
return;
}
bcemit_INS(fs, ins);
noins:
e->u.s.info = reg;
e->k = VNONRELOC;
}
/* Forward declaration. */
static BCPos bcemit_jmp(FuncState *fs);
/* Discharge an expression to a specific register. */
static void expr_toreg(FuncState *fs, ExpDesc *e, BCReg reg)
{
expr_toreg_nobranch(fs, e, reg);
if (e->k == VJMP)
jmp_append(fs, &e->t, e->u.s.info); /* Add it to the true jump list. */
if (expr_hasjump(e)) { /* Discharge expression with branches. */
BCPos jend, jfalse = NO_JMP, jtrue = NO_JMP;
if (jmp_novalue(fs, e->t) || jmp_novalue(fs, e->f)) {
BCPos jval = (e->k == VJMP) ? NO_JMP : bcemit_jmp(fs);
jfalse = bcemit_AD(fs, BC_KPRI, reg, VKFALSE);
bcemit_AJ(fs, BC_JMP, fs->freereg, 1);
jtrue = bcemit_AD(fs, BC_KPRI, reg, VKTRUE);
jmp_tohere(fs, jval);
}
jend = fs->pc;
fs->lasttarget = jend;
jmp_patchval(fs, e->f, jend, reg, jfalse);
jmp_patchval(fs, e->t, jend, reg, jtrue);
}
e->f = e->t = NO_JMP;
e->u.s.info = reg;
e->k = VNONRELOC;
}
/* Discharge an expression to the next free register. */
static void expr_tonextreg(FuncState *fs, ExpDesc *e)
{
expr_discharge(fs, e);
expr_free(fs, e);
bcreg_reserve(fs, 1);
expr_toreg(fs, e, fs->freereg - 1);
}
/* Discharge an expression to any register. */
static BCReg expr_toanyreg(FuncState *fs, ExpDesc *e)
{
expr_discharge(fs, e);
if (e->k == VNONRELOC) {
if (!expr_hasjump(e)) return e->u.s.info; /* Already in a register. */
if (e->u.s.info >= fs->nactvar) {
expr_toreg(fs, e, e->u.s.info); /* Discharge to temp. register. */
return e->u.s.info;
}
}
expr_tonextreg(fs, e); /* Discharge to next register. */
return e->u.s.info;
}
/* Partially discharge expression to a value. */
static void expr_toval(FuncState *fs, ExpDesc *e)
{
if (expr_hasjump(e))
expr_toanyreg(fs, e);
else
expr_discharge(fs, e);
}
/* Emit store for LHS expression. */
static void bcemit_store(FuncState *fs, ExpDesc *var, ExpDesc *e)
{
BCIns ins;
if (var->k == VLOCAL) {
fs->ls->vstack[var->u.s.aux].info |= VSTACK_VAR_RW;
expr_free(fs, e);
expr_toreg(fs, e, var->u.s.info);
return;
} else if (var->k == VUPVAL) {
fs->ls->vstack[var->u.s.aux].info |= VSTACK_VAR_RW;
expr_toval(fs, e);
if (e->k <= VKTRUE)
ins = BCINS_AD(BC_USETP, var->u.s.info, const_pri(e));
else if (e->k == VKSTR)
ins = BCINS_AD(BC_USETS, var->u.s.info, const_str(fs, e));
else if (e->k == VKNUM)
ins = BCINS_AD(BC_USETN, var->u.s.info, const_num(fs, e));
else
ins = BCINS_AD(BC_USETV, var->u.s.info, expr_toanyreg(fs, e));
} else if (var->k == VGLOBAL) {
BCReg ra = expr_toanyreg(fs, e);
ins = BCINS_AD(BC_GSET, ra, const_str(fs, var));
} else {
BCReg ra, rc;
lua_assert(var->k == VINDEXED);
ra = expr_toanyreg(fs, e);
rc = var->u.s.aux;
if ((int32_t)rc < 0) {
ins = BCINS_ABC(BC_TSETS, ra, var->u.s.info, ~rc);
} else if (rc > BCMAX_C) {
ins = BCINS_ABC(BC_TSETB, ra, var->u.s.info, rc-(BCMAX_C+1));
} else {
/* Free late alloced key reg to avoid assert on free of value reg. */
/* This can only happen when called from expr_table(). */
lua_assert(e->k != VNONRELOC || ra < fs->nactvar ||
rc < ra || (bcreg_free(fs, rc),1));
ins = BCINS_ABC(BC_TSETV, ra, var->u.s.info, rc);
}
}
bcemit_INS(fs, ins);
expr_free(fs, e);
}
/* Emit method lookup expression. */
static void bcemit_method(FuncState *fs, ExpDesc *e, ExpDesc *key)
{
BCReg idx, func, obj = expr_toanyreg(fs, e);
expr_free(fs, e);
func = fs->freereg;
bcemit_AD(fs, BC_MOV, func+1, obj); /* Copy object to first argument. */
lua_assert(expr_isstrk(key));
idx = const_str(fs, key);
if (idx <= BCMAX_C) {
bcreg_reserve(fs, 2);
bcemit_ABC(fs, BC_TGETS, func, obj, idx);
} else {
bcreg_reserve(fs, 3);
bcemit_AD(fs, BC_KSTR, func+2, idx);
bcemit_ABC(fs, BC_TGETV, func, obj, func+2);
fs->freereg--;
}
e->u.s.info = func;
e->k = VNONRELOC;
}
/* -- Bytecode emitter for branches --------------------------------------- */
/* Emit unconditional branch. */
static BCPos bcemit_jmp(FuncState *fs)
{
BCPos jpc = fs->jpc;
BCPos j = fs->pc - 1;
BCIns *ip = &fs->bcbase[j].ins;
fs->jpc = NO_JMP;
if ((int32_t)j >= (int32_t)fs->lasttarget && bc_op(*ip) == BC_UCLO)
setbc_j(ip, NO_JMP);
else
j = bcemit_AJ(fs, BC_JMP, fs->freereg, NO_JMP);
jmp_append(fs, &j, jpc);
return j;
}
/* Invert branch condition of bytecode instruction. */
static void invertcond(FuncState *fs, ExpDesc *e)
{
BCIns *ip = &fs->bcbase[e->u.s.info - 1].ins;
setbc_op(ip, bc_op(*ip)^1);
}
/* Emit conditional branch. */
static BCPos bcemit_branch(FuncState *fs, ExpDesc *e, int cond)
{
BCPos pc;
if (e->k == VRELOCABLE) {
BCIns *ip = bcptr(fs, e);
if (bc_op(*ip) == BC_NOT) {
*ip = BCINS_AD(cond ? BC_ISF : BC_IST, 0, bc_d(*ip));
return bcemit_jmp(fs);
}
}
if (e->k != VNONRELOC) {
bcreg_reserve(fs, 1);
expr_toreg_nobranch(fs, e, fs->freereg-1);
}
bcemit_AD(fs, cond ? BC_ISTC : BC_ISFC, NO_REG, e->u.s.info);
pc = bcemit_jmp(fs);
expr_free(fs, e);
return pc;
}
/* Emit branch on true condition. */
static void bcemit_branch_t(FuncState *fs, ExpDesc *e)
{
BCPos pc;
expr_discharge(fs, e);
if (e->k == VKSTR || e->k == VKNUM || e->k == VKTRUE)
pc = NO_JMP; /* Never jump. */
else if (e->k == VJMP)
invertcond(fs, e), pc = e->u.s.info;
else if (e->k == VKFALSE || e->k == VKNIL)
expr_toreg_nobranch(fs, e, NO_REG), pc = bcemit_jmp(fs);
else
pc = bcemit_branch(fs, e, 0);
jmp_append(fs, &e->f, pc);
jmp_tohere(fs, e->t);
e->t = NO_JMP;
}
/* Emit branch on false condition. */
static void bcemit_branch_f(FuncState *fs, ExpDesc *e)
{
BCPos pc;
expr_discharge(fs, e);
if (e->k == VKNIL || e->k == VKFALSE)
pc = NO_JMP; /* Never jump. */
else if (e->k == VJMP)
pc = e->u.s.info;
else if (e->k == VKSTR || e->k == VKNUM || e->k == VKTRUE)
expr_toreg_nobranch(fs, e, NO_REG), pc = bcemit_jmp(fs);
else
pc = bcemit_branch(fs, e, 1);
jmp_append(fs, &e->t, pc);
jmp_tohere(fs, e->f);
e->f = NO_JMP;
}
/* -- Bytecode emitter for operators -------------------------------------- */
/* Try constant-folding of arithmetic operators. */
static int foldarith(BinOpr opr, ExpDesc *e1, ExpDesc *e2)
{
TValue o;
lua_Number n;
if (!expr_isnumk_nojump(e1) || !expr_isnumk_nojump(e2)) return 0;
n = lj_vm_foldarith(expr_numberV(e1), expr_numberV(e2), (int)opr-OPR_ADD);
setnumV(&o, n);
if (tvisnan(&o) || tvismzero(&o)) return 0; /* Avoid NaN and -0 as consts. */
if (LJ_DUALNUM) {
int32_t k = lj_num2int(n);
if ((lua_Number)k == n) {
setintV(&e1->u.nval, k);
return 1;
}
}
setnumV(&e1->u.nval, n);
return 1;
}
/* Emit arithmetic operator. */
static void bcemit_arith(FuncState *fs, BinOpr opr, ExpDesc *e1, ExpDesc *e2)
{
BCReg rb, rc, t;
uint32_t op;
if (foldarith(opr, e1, e2))
return;
if (opr == OPR_POW) {
op = BC_POW;
rc = expr_toanyreg(fs, e2);
rb = expr_toanyreg(fs, e1);
} else {
op = opr-OPR_ADD+BC_ADDVV;
/* Must discharge 2nd operand first since VINDEXED might free regs. */
expr_toval(fs, e2);
if (expr_isnumk(e2) && (rc = const_num(fs, e2)) <= BCMAX_C)
op -= BC_ADDVV-BC_ADDVN;
else
rc = expr_toanyreg(fs, e2);
/* 1st operand discharged by bcemit_binop_left, but need KNUM/KSHORT. */
lua_assert(expr_isnumk(e1) || e1->k == VNONRELOC);
expr_toval(fs, e1);
/* Avoid two consts to satisfy bytecode constraints. */
if (expr_isnumk(e1) && !expr_isnumk(e2) &&
(t = const_num(fs, e1)) <= BCMAX_B) {
rb = rc; rc = t; op -= BC_ADDVV-BC_ADDNV;
} else {
rb = expr_toanyreg(fs, e1);
}
}
/* Using expr_free might cause asserts if the order is wrong. */
if (e1->k == VNONRELOC && e1->u.s.info >= fs->nactvar) fs->freereg--;
if (e2->k == VNONRELOC && e2->u.s.info >= fs->nactvar) fs->freereg--;
e1->u.s.info = bcemit_ABC(fs, op, 0, rb, rc);
e1->k = VRELOCABLE;
}
/* Emit comparison operator. */
static void bcemit_comp(FuncState *fs, BinOpr opr, ExpDesc *e1, ExpDesc *e2)
{
ExpDesc *eret = e1;
BCIns ins;
expr_toval(fs, e1);
if (opr == OPR_EQ || opr == OPR_NE) {
BCOp op = opr == OPR_EQ ? BC_ISEQV : BC_ISNEV;
BCReg ra;
if (expr_isk(e1)) { e1 = e2; e2 = eret; } /* Need constant in 2nd arg. */
ra = expr_toanyreg(fs, e1); /* First arg must be in a reg. */
expr_toval(fs, e2);
switch (e2->k) {
case VKNIL: case VKFALSE: case VKTRUE:
ins = BCINS_AD(op+(BC_ISEQP-BC_ISEQV), ra, const_pri(e2));
break;
case VKSTR:
ins = BCINS_AD(op+(BC_ISEQS-BC_ISEQV), ra, const_str(fs, e2));
break;
case VKNUM:
ins = BCINS_AD(op+(BC_ISEQN-BC_ISEQV), ra, const_num(fs, e2));
break;
default:
ins = BCINS_AD(op, ra, expr_toanyreg(fs, e2));
break;
}
} else {
uint32_t op = opr-OPR_LT+BC_ISLT;
BCReg ra, rd;
if ((op-BC_ISLT) & 1) { /* GT -> LT, GE -> LE */
e1 = e2; e2 = eret; /* Swap operands. */
op = ((op-BC_ISLT)^3)+BC_ISLT;
expr_toval(fs, e1);
}
rd = expr_toanyreg(fs, e2);
ra = expr_toanyreg(fs, e1);
ins = BCINS_AD(op, ra, rd);
}
/* Using expr_free might cause asserts if the order is wrong. */
if (e1->k == VNONRELOC && e1->u.s.info >= fs->nactvar) fs->freereg--;
if (e2->k == VNONRELOC && e2->u.s.info >= fs->nactvar) fs->freereg--;
bcemit_INS(fs, ins);
eret->u.s.info = bcemit_jmp(fs);
eret->k = VJMP;
}
/* Fixup left side of binary operator. */
static void bcemit_binop_left(FuncState *fs, BinOpr op, ExpDesc *e)
{
if (op == OPR_AND) {
bcemit_branch_t(fs, e);
} else if (op == OPR_OR) {
bcemit_branch_f(fs, e);
} else if (op == OPR_CONCAT) {
expr_tonextreg(fs, e);
} else if (op == OPR_EQ || op == OPR_NE) {
if (!expr_isk_nojump(e)) expr_toanyreg(fs, e);
} else {
if (!expr_isnumk_nojump(e)) expr_toanyreg(fs, e);
}
}
/* Emit binary operator. */
static void bcemit_binop(FuncState *fs, BinOpr op, ExpDesc *e1, ExpDesc *e2)
{
if (op <= OPR_POW) {
bcemit_arith(fs, op, e1, e2);
} else if (op == OPR_AND) {
lua_assert(e1->t == NO_JMP); /* List must be closed. */
expr_discharge(fs, e2);
jmp_append(fs, &e2->f, e1->f);
*e1 = *e2;
} else if (op == OPR_OR) {
lua_assert(e1->f == NO_JMP); /* List must be closed. */
expr_discharge(fs, e2);
jmp_append(fs, &e2->t, e1->t);
*e1 = *e2;
} else if (op == OPR_CONCAT) {
expr_toval(fs, e2);
if (e2->k == VRELOCABLE && bc_op(*bcptr(fs, e2)) == BC_CAT) {
lua_assert(e1->u.s.info == bc_b(*bcptr(fs, e2))-1);
expr_free(fs, e1);
setbc_b(bcptr(fs, e2), e1->u.s.info);
e1->u.s.info = e2->u.s.info;
} else {
expr_tonextreg(fs, e2);
expr_free(fs, e2);
expr_free(fs, e1);
e1->u.s.info = bcemit_ABC(fs, BC_CAT, 0, e1->u.s.info, e2->u.s.info);
}
e1->k = VRELOCABLE;
} else {
lua_assert(op == OPR_NE || op == OPR_EQ ||
op == OPR_LT || op == OPR_GE || op == OPR_LE || op == OPR_GT);
bcemit_comp(fs, op, e1, e2);
}
}
/* Emit unary operator. */
static void bcemit_unop(FuncState *fs, BCOp op, ExpDesc *e)
{
if (op == BC_NOT) {
/* Swap true and false lists. */
{ BCPos temp = e->f; e->f = e->t; e->t = temp; }
jmp_dropval(fs, e->f);
jmp_dropval(fs, e->t);
expr_discharge(fs, e);
if (e->k == VKNIL || e->k == VKFALSE) {
e->k = VKTRUE;
return;
} else if (expr_isk(e) || (LJ_HASFFI && e->k == VKCDATA)) {
e->k = VKFALSE;
return;
} else if (e->k == VJMP) {
invertcond(fs, e);
return;
} else if (e->k == VRELOCABLE) {
bcreg_reserve(fs, 1);
setbc_a(bcptr(fs, e), fs->freereg-1);
e->u.s.info = fs->freereg-1;
e->k = VNONRELOC;
} else {
lua_assert(e->k == VNONRELOC);
}
} else {
lua_assert(op == BC_UNM || op == BC_LEN);
if (op == BC_UNM && !expr_hasjump(e)) { /* Constant-fold negations. */
#if LJ_HASFFI
if (e->k == VKCDATA) { /* Fold in-place since cdata is not interned. */
GCcdata *cd = cdataV(&e->u.nval);
int64_t *p = (int64_t *)cdataptr(cd);
if (cd->ctypeid == CTID_COMPLEX_DOUBLE)
p[1] ^= (int64_t)U64x(80000000,00000000);
else
*p = -*p;
return;
} else
#endif
if (expr_isnumk(e) && !expr_numiszero(e)) { /* Avoid folding to -0. */
TValue *o = expr_numtv(e);
if (tvisint(o)) {
int32_t k = intV(o);
if (k == -k)
setnumV(o, -(lua_Number)k);
else
setintV(o, -k);
return;
} else {
o->u64 ^= U64x(80000000,00000000);
return;
}
}
}
expr_toanyreg(fs, e);
}
expr_free(fs, e);
e->u.s.info = bcemit_AD(fs, op, 0, e->u.s.info);
e->k = VRELOCABLE;
}
/* -- Lexer support ------------------------------------------------------- */
/* Check and consume optional token. */
static int lex_opt(LexState *ls, LexToken tok)
{
if (ls->token == tok) {
lj_lex_next(ls);
return 1;
}
return 0;
}
/* Check and consume token. */
static void lex_check(LexState *ls, LexToken tok)
{
if (ls->token != tok)
err_token(ls, tok);
lj_lex_next(ls);
}
/* Check for matching token. */
static void lex_match(LexState *ls, LexToken what, LexToken who, BCLine line)
{
if (!lex_opt(ls, what)) {
if (line == ls->linenumber) {
err_token(ls, what);
} else {
const char *swhat = lj_lex_token2str(ls, what);
const char *swho = lj_lex_token2str(ls, who);
lj_lex_error(ls, ls->token, LJ_ERR_XMATCH, swhat, swho, line);
}
}
}
/* Check for string token. */
static GCstr *lex_str(LexState *ls)
{
GCstr *s;
if (ls->token != TK_name && (LJ_52 || ls->token != TK_goto))
err_token(ls, TK_name);
s = strV(&ls->tokenval);
lj_lex_next(ls);
return s;
}
/* -- Variable handling --------------------------------------------------- */
#define var_get(ls, fs, i) ((ls)->vstack[(fs)->varmap[(i)]])
/* Define a new local variable. */
static void var_new(LexState *ls, BCReg n, GCstr *name)
{
FuncState *fs = ls->fs;
MSize vtop = ls->vtop;
checklimit(fs, fs->nactvar+n, LJ_MAX_LOCVAR, "local variables");
if (LJ_UNLIKELY(vtop >= ls->sizevstack)) {
if (ls->sizevstack >= LJ_MAX_VSTACK)
lj_lex_error(ls, 0, LJ_ERR_XLIMC, LJ_MAX_VSTACK);
lj_mem_growvec(ls->L, ls->vstack, ls->sizevstack, LJ_MAX_VSTACK, VarInfo);
}
lua_assert((uintptr_t)name < VARNAME__MAX ||
lj_tab_getstr(fs->kt, name) != NULL);
/* NOBARRIER: name is anchored in fs->kt and ls->vstack is not a GCobj. */
setgcref(ls->vstack[vtop].name, obj2gco(name));
fs->varmap[fs->nactvar+n] = (uint16_t)vtop;
ls->vtop = vtop+1;
}
#define var_new_lit(ls, n, v) \
var_new(ls, (n), lj_parse_keepstr(ls, "" v, sizeof(v)-1))
#define var_new_fixed(ls, n, vn) \
var_new(ls, (n), (GCstr *)(uintptr_t)(vn))
/* Add local variables. */
static void var_add(LexState *ls, BCReg nvars)
{
FuncState *fs = ls->fs;
BCReg nactvar = fs->nactvar;
while (nvars--) {
VarInfo *v = &var_get(ls, fs, nactvar);
v->startpc = fs->pc;
v->slot = nactvar++;
v->info = 0;
}
fs->nactvar = nactvar;
}
/* Remove local variables. */
static void var_remove(LexState *ls, BCReg tolevel)
{
FuncState *fs = ls->fs;
while (fs->nactvar > tolevel)
var_get(ls, fs, --fs->nactvar).endpc = fs->pc;
}
/* Lookup local variable name. */
static BCReg var_lookup_local(FuncState *fs, GCstr *n)
{
int i;
for (i = fs->nactvar-1; i >= 0; i--) {
if (n == strref(var_get(fs->ls, fs, i).name))
return (BCReg)i;
}
return (BCReg)-1; /* Not found. */
}
/* Lookup or add upvalue index. */
static MSize var_lookup_uv(FuncState *fs, MSize vidx, ExpDesc *e)
{
MSize i, n = fs->nuv;
for (i = 0; i < n; i++)
if (fs->uvmap[i] == vidx)
return i; /* Already exists. */
/* Otherwise create a new one. */
checklimit(fs, fs->nuv, LJ_MAX_UPVAL, "upvalues");
lua_assert(e->k == VLOCAL || e->k == VUPVAL);
fs->uvmap[n] = (uint16_t)vidx;
fs->uvtmp[n] = (uint16_t)(e->k == VLOCAL ? vidx : LJ_MAX_VSTACK+e->u.s.info);
fs->nuv = n+1;
return n;
}
/* Forward declaration. */
static void fscope_uvmark(FuncState *fs, BCReg level);
/* Recursively lookup variables in enclosing functions. */
static MSize var_lookup_(FuncState *fs, GCstr *name, ExpDesc *e, int first)
{
if (fs) {
BCReg reg = var_lookup_local(fs, name);
if ((int32_t)reg >= 0) { /* Local in this function? */
expr_init(e, VLOCAL, reg);
if (!first)
fscope_uvmark(fs, reg); /* Scope now has an upvalue. */
return (MSize)(e->u.s.aux = (uint32_t)fs->varmap[reg]);
} else {
MSize vidx = var_lookup_(fs->prev, name, e, 0); /* Var in outer func? */
if ((int32_t)vidx >= 0) { /* Yes, make it an upvalue here. */
e->u.s.info = (uint8_t)var_lookup_uv(fs, vidx, e);
e->k = VUPVAL;
return vidx;
}
}
} else { /* Not found in any function, must be a global. */
expr_init(e, VGLOBAL, 0);
e->u.sval = name;
}
return (MSize)-1; /* Global. */
}
/* Lookup variable name. */
#define var_lookup(ls, e) \
var_lookup_((ls)->fs, lex_str(ls), (e), 1)
/* -- Goto an label handling ---------------------------------------------- */
/* Add a new goto or label. */
static MSize gola_new(LexState *ls, GCstr *name, uint8_t info, BCPos pc)
{
FuncState *fs = ls->fs;
MSize vtop = ls->vtop;
if (LJ_UNLIKELY(vtop >= ls->sizevstack)) {
if (ls->sizevstack >= LJ_MAX_VSTACK)
lj_lex_error(ls, 0, LJ_ERR_XLIMC, LJ_MAX_VSTACK);
lj_mem_growvec(ls->L, ls->vstack, ls->sizevstack, LJ_MAX_VSTACK, VarInfo);
}
lua_assert(name == NAME_BREAK || lj_tab_getstr(fs->kt, name) != NULL);
/* NOBARRIER: name is anchored in fs->kt and ls->vstack is not a GCobj. */
setgcref(ls->vstack[vtop].name, obj2gco(name));
ls->vstack[vtop].startpc = pc;
ls->vstack[vtop].slot = (uint8_t)fs->nactvar;
ls->vstack[vtop].info = info;
ls->vtop = vtop+1;
return vtop;
}
#define gola_isgoto(v) ((v)->info & VSTACK_GOTO)
#define gola_islabel(v) ((v)->info & VSTACK_LABEL)
#define gola_isgotolabel(v) ((v)->info & (VSTACK_GOTO|VSTACK_LABEL))
/* Patch goto to jump to label. */
static void gola_patch(LexState *ls, VarInfo *vg, VarInfo *vl)
{
FuncState *fs = ls->fs;
BCPos pc = vg->startpc;
setgcrefnull(vg->name); /* Invalidate pending goto. */
setbc_a(&fs->bcbase[pc].ins, vl->slot);
jmp_patch(fs, pc, vl->startpc);
}
/* Patch goto to close upvalues. */
static void gola_close(LexState *ls, VarInfo *vg)
{
FuncState *fs = ls->fs;
BCPos pc = vg->startpc;
BCIns *ip = &fs->bcbase[pc].ins;
lua_assert(gola_isgoto(vg));
lua_assert(bc_op(*ip) == BC_JMP || bc_op(*ip) == BC_UCLO);
setbc_a(ip, vg->slot);
if (bc_op(*ip) == BC_JMP) {
BCPos next = jmp_next(fs, pc);
if (next != NO_JMP) jmp_patch(fs, next, pc); /* Jump to UCLO. */
setbc_op(ip, BC_UCLO); /* Turn into UCLO. */
setbc_j(ip, NO_JMP);
}
}
/* Resolve pending forward gotos for label. */
static void gola_resolve(LexState *ls, FuncScope *bl, MSize idx)
{
VarInfo *vg = ls->vstack + bl->vstart;
VarInfo *vl = ls->vstack + idx;
for (; vg < vl; vg++)
if (gcrefeq(vg->name, vl->name) && gola_isgoto(vg)) {
if (vg->slot < vl->slot) {
GCstr *name = strref(var_get(ls, ls->fs, vg->slot).name);
lua_assert((uintptr_t)name >= VARNAME__MAX);
ls->linenumber = ls->fs->bcbase[vg->startpc].line;
lua_assert(strref(vg->name) != NAME_BREAK);
lj_lex_error(ls, 0, LJ_ERR_XGSCOPE,
strdata(strref(vg->name)), strdata(name));
}
gola_patch(ls, vg, vl);
}
}
/* Fixup remaining gotos and labels for scope. */
static void gola_fixup(LexState *ls, FuncScope *bl)
{
VarInfo *v = ls->vstack + bl->vstart;
VarInfo *ve = ls->vstack + ls->vtop;
for (; v < ve; v++) {
GCstr *name = strref(v->name);
if (name != NULL) { /* Only consider remaining valid gotos/labels. */
if (gola_islabel(v)) {
VarInfo *vg;
setgcrefnull(v->name); /* Invalidate label that goes out of scope. */
for (vg = v+1; vg < ve; vg++) /* Resolve pending backward gotos. */
if (strref(vg->name) == name && gola_isgoto(vg)) {
if ((bl->flags&FSCOPE_UPVAL) && vg->slot > v->slot)
gola_close(ls, vg);
gola_patch(ls, vg, v);
}
} else if (gola_isgoto(v)) {
if (bl->prev) { /* Propagate goto or break to outer scope. */
bl->prev->flags |= name == NAME_BREAK ? FSCOPE_BREAK : FSCOPE_GOLA;
v->slot = bl->nactvar;
if ((bl->flags & FSCOPE_UPVAL))
gola_close(ls, v);
} else { /* No outer scope: undefined goto label or no loop. */
ls->linenumber = ls->fs->bcbase[v->startpc].line;
if (name == NAME_BREAK)
lj_lex_error(ls, 0, LJ_ERR_XBREAK);
else
lj_lex_error(ls, 0, LJ_ERR_XLUNDEF, strdata(name));
}
}
}
}
}
/* Find existing label. */
static VarInfo *gola_findlabel(LexState *ls, GCstr *name)
{
VarInfo *v = ls->vstack + ls->fs->bl->vstart;
VarInfo *ve = ls->vstack + ls->vtop;
for (; v < ve; v++)
if (strref(v->name) == name && gola_islabel(v))
return v;
return NULL;
}
/* -- Scope handling ------------------------------------------------------ */
/* Begin a scope. */
static void fscope_begin(FuncState *fs, FuncScope *bl, int flags)
{
bl->nactvar = (uint8_t)fs->nactvar;
bl->flags = flags;
bl->vstart = fs->ls->vtop;
bl->prev = fs->bl;
fs->bl = bl;
lua_assert(fs->freereg == fs->nactvar);
}
/* End a scope. */
static void fscope_end(FuncState *fs)
{
FuncScope *bl = fs->bl;
LexState *ls = fs->ls;
fs->bl = bl->prev;
var_remove(ls, bl->nactvar);
fs->freereg = fs->nactvar;
lua_assert(bl->nactvar == fs->nactvar);
if ((bl->flags & (FSCOPE_UPVAL|FSCOPE_NOCLOSE)) == FSCOPE_UPVAL)
bcemit_AJ(fs, BC_UCLO, bl->nactvar, 0);
if ((bl->flags & FSCOPE_BREAK)) {
if ((bl->flags & FSCOPE_LOOP)) {
MSize idx = gola_new(ls, NAME_BREAK, VSTACK_LABEL, fs->pc);
ls->vtop = idx; /* Drop break label immediately. */
gola_resolve(ls, bl, idx);
return;
} /* else: need the fixup step to propagate the breaks. */
} else if (!(bl->flags & FSCOPE_GOLA)) {
return;
}
gola_fixup(ls, bl);
}
/* Mark scope as having an upvalue. */
static void fscope_uvmark(FuncState *fs, BCReg level)
{
FuncScope *bl;
for (bl = fs->bl; bl && bl->nactvar > level; bl = bl->prev)
;
if (bl)
bl->flags |= FSCOPE_UPVAL;
}
/* -- Function state management ------------------------------------------- */
/* Fixup bytecode for prototype. */
static void fs_fixup_bc(FuncState *fs, GCproto *pt, BCIns *bc, MSize n)
{
BCInsLine *base = fs->bcbase;
MSize i;
pt->sizebc = n;
bc[0] = BCINS_AD((fs->flags & PROTO_VARARG) ? BC_FUNCV : BC_FUNCF,
fs->framesize, 0);
for (i = 1; i < n; i++)
bc[i] = base[i].ins;
}
/* Fixup upvalues for child prototype, step #2. */
static void fs_fixup_uv2(FuncState *fs, GCproto *pt)
{
VarInfo *vstack = fs->ls->vstack;
uint16_t *uv = proto_uv(pt);
MSize i, n = pt->sizeuv;
for (i = 0; i < n; i++) {
VarIndex vidx = uv[i];
if (vidx >= LJ_MAX_VSTACK)
uv[i] = vidx - LJ_MAX_VSTACK;
else if ((vstack[vidx].info & VSTACK_VAR_RW))
uv[i] = vstack[vidx].slot | PROTO_UV_LOCAL;
else
uv[i] = vstack[vidx].slot | PROTO_UV_LOCAL | PROTO_UV_IMMUTABLE;
}
}
/* Fixup constants for prototype. */
static void fs_fixup_k(FuncState *fs, GCproto *pt, void *kptr)
{
GCtab *kt;
TValue *array;
Node *node;
MSize i, hmask;
checklimitgt(fs, fs->nkn, BCMAX_D+1, "constants");
checklimitgt(fs, fs->nkgc, BCMAX_D+1, "constants");
setmref(pt->k, kptr);
pt->sizekn = fs->nkn;
pt->sizekgc = fs->nkgc;
kt = fs->kt;
array = tvref(kt->array);
for (i = 0; i < kt->asize; i++)
if (tvhaskslot(&array[i])) {
TValue *tv = &((TValue *)kptr)[tvkslot(&array[i])];
if (LJ_DUALNUM)
setintV(tv, (int32_t)i);
else
setnumV(tv, (lua_Number)i);
}
node = noderef(kt->node);
hmask = kt->hmask;
for (i = 0; i <= hmask; i++) {
Node *n = &node[i];
if (tvhaskslot(&n->val)) {
ptrdiff_t kidx = (ptrdiff_t)tvkslot(&n->val);
lua_assert(!tvisint(&n->key));
if (tvisnum(&n->key)) {
TValue *tv = &((TValue *)kptr)[kidx];
if (LJ_DUALNUM) {
lua_Number nn = numV(&n->key);
int32_t k = lj_num2int(nn);
lua_assert(!tvismzero(&n->key));
if ((lua_Number)k == nn)
setintV(tv, k);
else
*tv = n->key;
} else {
*tv = n->key;
}
} else {
GCobj *o = gcV(&n->key);
setgcref(((GCRef *)kptr)[~kidx], o);
lj_gc_objbarrier(fs->L, pt, o);
if (tvisproto(&n->key))
fs_fixup_uv2(fs, gco2pt(o));
}
}
}
}
/* Fixup upvalues for prototype, step #1. */
static void fs_fixup_uv1(FuncState *fs, GCproto *pt, uint16_t *uv)
{
setmref(pt->uv, uv);
pt->sizeuv = fs->nuv;
memcpy(uv, fs->uvtmp, fs->nuv*sizeof(VarIndex));
}
#ifndef LUAJIT_DISABLE_DEBUGINFO
/* Prepare lineinfo for prototype. */
static size_t fs_prep_line(FuncState *fs, BCLine numline)
{
return (fs->pc-1) << (numline < 256 ? 0 : numline < 65536 ? 1 : 2);
}
/* Fixup lineinfo for prototype. */
static void fs_fixup_line(FuncState *fs, GCproto *pt,
void *lineinfo, BCLine numline)
{
BCInsLine *base = fs->bcbase + 1;
BCLine first = fs->linedefined;
MSize i = 0, n = fs->pc-1;
pt->firstline = fs->linedefined;
pt->numline = numline;
setmref(pt->lineinfo, lineinfo);
if (LJ_LIKELY(numline < 256)) {
uint8_t *li = (uint8_t *)lineinfo;
do {
BCLine delta = base[i].line - first;
lua_assert(delta >= 0 && delta < 256);
li[i] = (uint8_t)delta;
} while (++i < n);
} else if (LJ_LIKELY(numline < 65536)) {
uint16_t *li = (uint16_t *)lineinfo;
do {
BCLine delta = base[i].line - first;
lua_assert(delta >= 0 && delta < 65536);
li[i] = (uint16_t)delta;
} while (++i < n);
} else {
uint32_t *li = (uint32_t *)lineinfo;
do {
BCLine delta = base[i].line - first;
lua_assert(delta >= 0);
li[i] = (uint32_t)delta;
} while (++i < n);
}
}
/* Resize buffer if needed. */
static LJ_NOINLINE void fs_buf_resize(LexState *ls, MSize len)
{
MSize sz = ls->sb.sz * 2;
while (ls->sb.n + len > sz) sz = sz * 2;
lj_str_resizebuf(ls->L, &ls->sb, sz);
}
static LJ_AINLINE void fs_buf_need(LexState *ls, MSize len)
{
if (LJ_UNLIKELY(ls->sb.n + len > ls->sb.sz))
fs_buf_resize(ls, len);
}
/* Add string to buffer. */
static void fs_buf_str(LexState *ls, const char *str, MSize len)
{
char *p = ls->sb.buf + ls->sb.n;
MSize i;
ls->sb.n += len;
for (i = 0; i < len; i++) p[i] = str[i];
}
/* Add ULEB128 value to buffer. */
static void fs_buf_uleb128(LexState *ls, uint32_t v)
{
MSize n = ls->sb.n;
uint8_t *p = (uint8_t *)ls->sb.buf;
for (; v >= 0x80; v >>= 7)
p[n++] = (uint8_t)((v & 0x7f) | 0x80);
p[n++] = (uint8_t)v;
ls->sb.n = n;
}
/* Prepare variable info for prototype. */
static size_t fs_prep_var(LexState *ls, FuncState *fs, size_t *ofsvar)
{
VarInfo *vs =ls->vstack, *ve;
MSize i, n;
BCPos lastpc;
lj_str_resetbuf(&ls->sb); /* Copy to temp. string buffer. */
/* Store upvalue names. */
for (i = 0, n = fs->nuv; i < n; i++) {
GCstr *s = strref(vs[fs->uvmap[i]].name);
MSize len = s->len+1;
fs_buf_need(ls, len);
fs_buf_str(ls, strdata(s), len);
}
*ofsvar = ls->sb.n;
lastpc = 0;
/* Store local variable names and compressed ranges. */
for (ve = vs + ls->vtop, vs += fs->vbase; vs < ve; vs++) {
if (!gola_isgotolabel(vs)) {
GCstr *s = strref(vs->name);
BCPos startpc;
if ((uintptr_t)s < VARNAME__MAX) {
fs_buf_need(ls, 1 + 2*5);
ls->sb.buf[ls->sb.n++] = (uint8_t)(uintptr_t)s;
} else {
MSize len = s->len+1;
fs_buf_need(ls, len + 2*5);
fs_buf_str(ls, strdata(s), len);
}
startpc = vs->startpc;
fs_buf_uleb128(ls, startpc-lastpc);
fs_buf_uleb128(ls, vs->endpc-startpc);
lastpc = startpc;
}
}
fs_buf_need(ls, 1);
ls->sb.buf[ls->sb.n++] = '\0'; /* Terminator for varinfo. */
return ls->sb.n;
}
/* Fixup variable info for prototype. */
static void fs_fixup_var(LexState *ls, GCproto *pt, uint8_t *p, size_t ofsvar)
{
setmref(pt->uvinfo, p);
setmref(pt->varinfo, (char *)p + ofsvar);
memcpy(p, ls->sb.buf, ls->sb.n); /* Copy from temp. string buffer. */
}
#else
/* Initialize with empty debug info, if disabled. */
#define fs_prep_line(fs, numline) (UNUSED(numline), 0)
#define fs_fixup_line(fs, pt, li, numline) \
pt->firstline = pt->numline = 0, setmref((pt)->lineinfo, NULL)
#define fs_prep_var(ls, fs, ofsvar) (UNUSED(ofsvar), 0)
#define fs_fixup_var(ls, pt, p, ofsvar) \
setmref((pt)->uvinfo, NULL), setmref((pt)->varinfo, NULL)
#endif
/* Check if bytecode op returns. */
static int bcopisret(BCOp op)
{
switch (op) {
case BC_CALLMT: case BC_CALLT:
case BC_RETM: case BC_RET: case BC_RET0: case BC_RET1:
return 1;
default:
return 0;
}
}
/* Fixup return instruction for prototype. */
static void fs_fixup_ret(FuncState *fs)
{
BCPos lastpc = fs->pc;
if (lastpc <= fs->lasttarget || !bcopisret(bc_op(fs->bcbase[lastpc-1].ins))) {
if ((fs->bl->flags & FSCOPE_UPVAL))
bcemit_AJ(fs, BC_UCLO, 0, 0);
bcemit_AD(fs, BC_RET0, 0, 1); /* Need final return. */
}
fs->bl->flags |= FSCOPE_NOCLOSE; /* Handled above. */
fscope_end(fs);
lua_assert(fs->bl == NULL);
/* May need to fixup returns encoded before first function was created. */
if (fs->flags & PROTO_FIXUP_RETURN) {
BCPos pc;
for (pc = 1; pc < lastpc; pc++) {
BCIns ins = fs->bcbase[pc].ins;
BCPos offset;
switch (bc_op(ins)) {
case BC_CALLMT: case BC_CALLT:
case BC_RETM: case BC_RET: case BC_RET0: case BC_RET1:
offset = bcemit_INS(fs, ins); /* Copy original instruction. */
fs->bcbase[offset].line = fs->bcbase[pc].line;
offset = offset-(pc+1)+BCBIAS_J;
if (offset > BCMAX_D)
err_syntax(fs->ls, LJ_ERR_XFIXUP);
/* Replace with UCLO plus branch. */
fs->bcbase[pc].ins = BCINS_AD(BC_UCLO, 0, offset);
break;
case BC_UCLO:
return; /* We're done. */
default:
break;
}
}
}
}
/* Finish a FuncState and return the new prototype. */
static GCproto *fs_finish(LexState *ls, BCLine line)
{
lua_State *L = ls->L;
FuncState *fs = ls->fs;
BCLine numline = line - fs->linedefined;
size_t sizept, ofsk, ofsuv, ofsli, ofsdbg, ofsvar;
GCproto *pt;
/* Apply final fixups. */
fs_fixup_ret(fs);
/* Calculate total size of prototype including all colocated arrays. */
sizept = sizeof(GCproto) + fs->pc*sizeof(BCIns) + fs->nkgc*sizeof(GCRef);
sizept = (sizept + sizeof(TValue)-1) & ~(sizeof(TValue)-1);
ofsk = sizept; sizept += fs->nkn*sizeof(TValue);
ofsuv = sizept; sizept += ((fs->nuv+1)&~1)*2;
ofsli = sizept; sizept += fs_prep_line(fs, numline);
ofsdbg = sizept; sizept += fs_prep_var(ls, fs, &ofsvar);
/* Allocate prototype and initialize its fields. */
pt = (GCproto *)lj_mem_newgco(L, (MSize)sizept);
pt->gct = ~LJ_TPROTO;
pt->sizept = (MSize)sizept;
pt->trace = 0;
pt->flags = (uint8_t)(fs->flags & ~(PROTO_HAS_RETURN|PROTO_FIXUP_RETURN));
pt->numparams = fs->numparams;
pt->framesize = fs->framesize;
setgcref(pt->chunkname, obj2gco(ls->chunkname));
/* Close potentially uninitialized gap between bc and kgc. */
*(uint32_t *)((char *)pt + ofsk - sizeof(GCRef)*(fs->nkgc+1)) = 0;
fs_fixup_bc(fs, pt, (BCIns *)((char *)pt + sizeof(GCproto)), fs->pc);
fs_fixup_k(fs, pt, (void *)((char *)pt + ofsk));
fs_fixup_uv1(fs, pt, (uint16_t *)((char *)pt + ofsuv));
fs_fixup_line(fs, pt, (void *)((char *)pt + ofsli), numline);
fs_fixup_var(ls, pt, (uint8_t *)((char *)pt + ofsdbg), ofsvar);
lj_vmevent_send(L, BC,
setprotoV(L, L->top++, pt);
);
L->top--; /* Pop table of constants. */
ls->vtop = fs->vbase; /* Reset variable stack. */
ls->fs = fs->prev;
lua_assert(ls->fs != NULL || ls->token == TK_eof);
return pt;
}
/* Initialize a new FuncState. */
static void fs_init(LexState *ls, FuncState *fs)
{
lua_State *L = ls->L;
fs->prev = ls->fs; ls->fs = fs; /* Append to list. */
fs->ls = ls;
fs->vbase = ls->vtop;
fs->L = L;
fs->pc = 0;
fs->lasttarget = 0;
fs->jpc = NO_JMP;
fs->freereg = 0;
fs->nkgc = 0;
fs->nkn = 0;
fs->nactvar = 0;
fs->nuv = 0;
fs->bl = NULL;
fs->flags = 0;
fs->framesize = 1; /* Minimum frame size. */
fs->kt = lj_tab_new(L, 0, 0);
/* Anchor table of constants in stack to avoid being collected. */
settabV(L, L->top, fs->kt);
incr_top(L);
}
/* -- Expressions --------------------------------------------------------- */
/* Forward declaration. */
static void expr(LexState *ls, ExpDesc *v);
/* Return string expression. */
static void expr_str(LexState *ls, ExpDesc *e)
{
expr_init(e, VKSTR, 0);
e->u.sval = lex_str(ls);
}
/* Return index expression. */
static void expr_index(FuncState *fs, ExpDesc *t, ExpDesc *e)
{
/* Already called: expr_toval(fs, e). */
t->k = VINDEXED;
if (expr_isnumk(e)) {
#if LJ_DUALNUM
if (tvisint(expr_numtv(e))) {
int32_t k = intV(expr_numtv(e));
if (checku8(k)) {
t->u.s.aux = BCMAX_C+1+(uint32_t)k; /* 256..511: const byte key */
return;
}
}
#else
lua_Number n = expr_numberV(e);
int32_t k = lj_num2int(n);
if (checku8(k) && n == (lua_Number)k) {
t->u.s.aux = BCMAX_C+1+(uint32_t)k; /* 256..511: const byte key */
return;
}
#endif
} else if (expr_isstrk(e)) {
BCReg idx = const_str(fs, e);
if (idx <= BCMAX_C) {
t->u.s.aux = ~idx; /* -256..-1: const string key */
return;
}
}
t->u.s.aux = expr_toanyreg(fs, e); /* 0..255: register */
}
/* Parse index expression with named field. */
static void expr_field(LexState *ls, ExpDesc *v)
{
FuncState *fs = ls->fs;
ExpDesc key;
expr_toanyreg(fs, v);
lj_lex_next(ls); /* Skip dot or colon. */
expr_str(ls, &key);
expr_index(fs, v, &key);
}
/* Parse index expression with brackets. */
static void expr_bracket(LexState *ls, ExpDesc *v)
{
lj_lex_next(ls); /* Skip '['. */
expr(ls, v);
expr_toval(ls->fs, v);
lex_check(ls, ']');
}
/* Get value of constant expression. */
static void expr_kvalue(TValue *v, ExpDesc *e)
{
if (e->k <= VKTRUE) {
setitype(v, ~(uint32_t)e->k);
} else if (e->k == VKSTR) {
setgcref(v->gcr, obj2gco(e->u.sval));
setitype(v, LJ_TSTR);
} else {
lua_assert(tvisnumber(expr_numtv(e)));
*v = *expr_numtv(e);
}
}
/* Parse table constructor expression. */
static void expr_table(LexState *ls, ExpDesc *e)
{
FuncState *fs = ls->fs;
BCLine line = ls->linenumber;
GCtab *t = NULL;
int vcall = 0, needarr = 0, fixt = 0;
uint32_t narr = 1; /* First array index. */
uint32_t nhash = 0; /* Number of hash entries. */
BCReg freg = fs->freereg;
BCPos pc = bcemit_AD(fs, BC_TNEW, freg, 0);
expr_init(e, VNONRELOC, freg);
bcreg_reserve(fs, 1);
freg++;
lex_check(ls, '{');
while (ls->token != '}') {
ExpDesc key, val;
vcall = 0;
if (ls->token == '[') {
expr_bracket(ls, &key); /* Already calls expr_toval. */
if (!expr_isk(&key)) expr_index(fs, e, &key);
if (expr_isnumk(&key) && expr_numiszero(&key)) needarr = 1; else nhash++;
lex_check(ls, '=');
} else if ((ls->token == TK_name || (!LJ_52 && ls->token == TK_goto)) &&
lj_lex_lookahead(ls) == '=') {
expr_str(ls, &key);
lex_check(ls, '=');
nhash++;
} else {
expr_init(&key, VKNUM, 0);
setintV(&key.u.nval, (int)narr);
narr++;
needarr = vcall = 1;
}
expr(ls, &val);
if (expr_isk(&key) && key.k != VKNIL &&
(key.k == VKSTR || expr_isk_nojump(&val))) {
TValue k, *v;
if (!t) { /* Create template table on demand. */
BCReg kidx;
t = lj_tab_new(fs->L, needarr ? narr : 0, hsize2hbits(nhash));
kidx = const_gc(fs, obj2gco(t), LJ_TTAB);
fs->bcbase[pc].ins = BCINS_AD(BC_TDUP, freg-1, kidx);
}
vcall = 0;
expr_kvalue(&k, &key);
v = lj_tab_set(fs->L, t, &k);
lj_gc_anybarriert(fs->L, t);
if (expr_isk_nojump(&val)) { /* Add const key/value to template table. */
expr_kvalue(v, &val);
} else { /* Otherwise create dummy string key (avoids lj_tab_newkey). */
settabV(fs->L, v, t); /* Preserve key with table itself as value. */
fixt = 1; /* Fix this later, after all resizes. */
goto nonconst;
}
} else {
nonconst:
if (val.k != VCALL) { expr_toanyreg(fs, &val); vcall = 0; }
if (expr_isk(&key)) expr_index(fs, e, &key);
bcemit_store(fs, e, &val);
}
fs->freereg = freg;
if (!lex_opt(ls, ',') && !lex_opt(ls, ';')) break;
}
lex_match(ls, '}', '{', line);
if (vcall) {
BCInsLine *ilp = &fs->bcbase[fs->pc-1];
ExpDesc en;
lua_assert(bc_a(ilp->ins) == freg &&
bc_op(ilp->ins) == (narr > 256 ? BC_TSETV : BC_TSETB));
expr_init(&en, VKNUM, 0);
en.u.nval.u32.lo = narr-1;
en.u.nval.u32.hi = 0x43300000; /* Biased integer to avoid denormals. */
if (narr > 256) { fs->pc--; ilp--; }
ilp->ins = BCINS_AD(BC_TSETM, freg, const_num(fs, &en));
setbc_b(&ilp[-1].ins, 0);
}
if (pc == fs->pc-1) { /* Make expr relocable if possible. */
e->u.s.info = pc;
fs->freereg--;
e->k = VRELOCABLE;
} else {
e->k = VNONRELOC; /* May have been changed by expr_index. */
}
if (!t) { /* Construct TNEW RD: hhhhhaaaaaaaaaaa. */
BCIns *ip = &fs->bcbase[pc].ins;
if (!needarr) narr = 0;
else if (narr < 3) narr = 3;
else if (narr > 0x7ff) narr = 0x7ff;
setbc_d(ip, narr|(hsize2hbits(nhash)<<11));
} else {
if (needarr && t->asize < narr)
lj_tab_reasize(fs->L, t, narr-1);
if (fixt) { /* Fix value for dummy keys in template table. */
Node *node = noderef(t->node);
uint32_t i, hmask = t->hmask;
for (i = 0; i <= hmask; i++) {
Node *n = &node[i];
if (tvistab(&n->val)) {
lua_assert(tabV(&n->val) == t);
setnilV(&n->val); /* Turn value into nil. */
}
}
}
lj_gc_check(fs->L);
}
}
/* Parse function parameters. */
static BCReg parse_params(LexState *ls, int needself)
{
FuncState *fs = ls->fs;
BCReg nparams = 0;
lex_check(ls, '(');
if (needself)
var_new_lit(ls, nparams++, "self");
if (ls->token != ')') {
do {
if (ls->token == TK_name || (!LJ_52 && ls->token == TK_goto)) {
var_new(ls, nparams++, lex_str(ls));
} else if (ls->token == TK_dots) {
lj_lex_next(ls);
fs->flags |= PROTO_VARARG;
break;
} else {
err_syntax(ls, LJ_ERR_XPARAM);
}
} while (lex_opt(ls, ','));
}
var_add(ls, nparams);
lua_assert(fs->nactvar == nparams);
bcreg_reserve(fs, nparams);
lex_check(ls, ')');
return nparams;
}
/* Forward declaration. */
static void parse_chunk(LexState *ls);
/* Parse body of a function. */
static void parse_body(LexState *ls, ExpDesc *e, int needself, BCLine line)
{
FuncState fs, *pfs = ls->fs;
FuncScope bl;
GCproto *pt;
ptrdiff_t oldbase = pfs->bcbase - ls->bcstack;
fs_init(ls, &fs);
fscope_begin(&fs, &bl, 0);
fs.linedefined = line;
fs.numparams = (uint8_t)parse_params(ls, needself);
fs.bcbase = pfs->bcbase + pfs->pc;
fs.bclim = pfs->bclim - pfs->pc;
bcemit_AD(&fs, BC_FUNCF, 0, 0); /* Placeholder. */
parse_chunk(ls);
if (ls->token != TK_end) lex_match(ls, TK_end, TK_function, line);
pt = fs_finish(ls, (ls->lastline = ls->linenumber));
pfs->bcbase = ls->bcstack + oldbase; /* May have been reallocated. */
pfs->bclim = (BCPos)(ls->sizebcstack - oldbase);
/* Store new prototype in the constant array of the parent. */
expr_init(e, VRELOCABLE,
bcemit_AD(pfs, BC_FNEW, 0, const_gc(pfs, obj2gco(pt), LJ_TPROTO)));
#if LJ_HASFFI
pfs->flags |= (fs.flags & PROTO_FFI);
#endif
if (!(pfs->flags & PROTO_CHILD)) {
if (pfs->flags & PROTO_HAS_RETURN)
pfs->flags |= PROTO_FIXUP_RETURN;
pfs->flags |= PROTO_CHILD;
}
lj_lex_next(ls);
}
/* Parse expression list. Last expression is left open. */
static BCReg expr_list(LexState *ls, ExpDesc *v)
{
BCReg n = 1;
expr(ls, v);
while (lex_opt(ls, ',')) {
expr_tonextreg(ls->fs, v);
expr(ls, v);
n++;
}
return n;
}
/* Parse function argument list. */
static void parse_args(LexState *ls, ExpDesc *e)
{
FuncState *fs = ls->fs;
ExpDesc args;
BCIns ins;
BCReg base;
BCLine line = ls->linenumber;
if (ls->token == '(') {
#if !LJ_52
if (line != ls->lastline)
err_syntax(ls, LJ_ERR_XAMBIG);
#endif
lj_lex_next(ls);
if (ls->token == ')') { /* f(). */
args.k = VVOID;
} else {
expr_list(ls, &args);
if (args.k == VCALL) /* f(a, b, g()) or f(a, b, ...). */
setbc_b(bcptr(fs, &args), 0); /* Pass on multiple results. */
}
lex_match(ls, ')', '(', line);
} else if (ls->token == '{') {
expr_table(ls, &args);
} else if (ls->token == TK_string) {
expr_init(&args, VKSTR, 0);
args.u.sval = strV(&ls->tokenval);
lj_lex_next(ls);
} else {
err_syntax(ls, LJ_ERR_XFUNARG);
return; /* Silence compiler. */
}
lua_assert(e->k == VNONRELOC);
base = e->u.s.info; /* Base register for call. */
if (args.k == VCALL) {
ins = BCINS_ABC(BC_CALLM, base, 2, args.u.s.aux - base - 1);
} else {
if (args.k != VVOID)
expr_tonextreg(fs, &args);
ins = BCINS_ABC(BC_CALL, base, 2, fs->freereg - base);
}
expr_init(e, VCALL, bcemit_INS(fs, ins));
e->u.s.aux = base;
fs->bcbase[fs->pc - 1].line = line;
fs->freereg = base+1; /* Leave one result by default. */
}
/* Parse primary expression. */
static void expr_primary(LexState *ls, ExpDesc *v)
{
FuncState *fs = ls->fs;
/* Parse prefix expression. */
if (ls->token == '(') {
BCLine line = ls->linenumber;
lj_lex_next(ls);
expr(ls, v);
lex_match(ls, ')', '(', line);
expr_discharge(ls->fs, v);
} else if (ls->token == TK_name || (!LJ_52 && ls->token == TK_goto)) {
var_lookup(ls, v);
} else {
err_syntax(ls, LJ_ERR_XSYMBOL);
}
for (;;) { /* Parse multiple expression suffixes. */
if (ls->token == '.') {
expr_field(ls, v);
} else if (ls->token == '[') {
ExpDesc key;
expr_toanyreg(fs, v);
expr_bracket(ls, &key);
expr_index(fs, v, &key);
} else if (ls->token == ':') {
ExpDesc key;
lj_lex_next(ls);
expr_str(ls, &key);
bcemit_method(fs, v, &key);
parse_args(ls, v);
} else if (ls->token == '(' || ls->token == TK_string || ls->token == '{') {
expr_tonextreg(fs, v);
parse_args(ls, v);
} else {
break;
}
}
}
/* Parse simple expression. */
static void expr_simple(LexState *ls, ExpDesc *v)
{
switch (ls->token) {
case TK_number:
expr_init(v, (LJ_HASFFI && tviscdata(&ls->tokenval)) ? VKCDATA : VKNUM, 0);
copyTV(ls->L, &v->u.nval, &ls->tokenval);
break;
case TK_string:
expr_init(v, VKSTR, 0);
v->u.sval = strV(&ls->tokenval);
break;
case TK_nil:
expr_init(v, VKNIL, 0);
break;
case TK_true:
expr_init(v, VKTRUE, 0);
break;
case TK_false:
expr_init(v, VKFALSE, 0);
break;
case TK_dots: { /* Vararg. */
FuncState *fs = ls->fs;
BCReg base;
checkcond(ls, fs->flags & PROTO_VARARG, LJ_ERR_XDOTS);
bcreg_reserve(fs, 1);
base = fs->freereg-1;
expr_init(v, VCALL, bcemit_ABC(fs, BC_VARG, base, 2, fs->numparams));
v->u.s.aux = base;
break;
}
case '{': /* Table constructor. */
expr_table(ls, v);
return;
case TK_function:
lj_lex_next(ls);
parse_body(ls, v, 0, ls->linenumber);
return;
default:
expr_primary(ls, v);
return;
}
lj_lex_next(ls);
}
/* Manage syntactic levels to avoid blowing up the stack. */
static void synlevel_begin(LexState *ls)
{
if (++ls->level >= LJ_MAX_XLEVEL)
lj_lex_error(ls, 0, LJ_ERR_XLEVELS);
}
#define synlevel_end(ls) ((ls)->level--)
/* Convert token to binary operator. */
static BinOpr token2binop(LexToken tok)
{
switch (tok) {
case '+': return OPR_ADD;
case '-': return OPR_SUB;
case '*': return OPR_MUL;
case '/': return OPR_DIV;
case '%': return OPR_MOD;
case '^': return OPR_POW;
case TK_concat: return OPR_CONCAT;
case TK_ne: return OPR_NE;
case TK_eq: return OPR_EQ;
case '<': return OPR_LT;
case TK_le: return OPR_LE;
case '>': return OPR_GT;
case TK_ge: return OPR_GE;
case TK_and: return OPR_AND;
case TK_or: return OPR_OR;
default: return OPR_NOBINOPR;
}
}
/* Priorities for each binary operator. ORDER OPR. */
static const struct {
uint8_t left; /* Left priority. */
uint8_t right; /* Right priority. */
} priority[] = {
{6,6}, {6,6}, {7,7}, {7,7}, {7,7}, /* ADD SUB MUL DIV MOD */
{10,9}, {5,4}, /* POW CONCAT (right associative) */
{3,3}, {3,3}, /* EQ NE */
{3,3}, {3,3}, {3,3}, {3,3}, /* LT GE GT LE */
{2,2}, {1,1} /* AND OR */
};
#define UNARY_PRIORITY 8 /* Priority for unary operators. */
/* Forward declaration. */
static BinOpr expr_binop(LexState *ls, ExpDesc *v, uint32_t limit);
/* Parse unary expression. */
static void expr_unop(LexState *ls, ExpDesc *v)
{
BCOp op;
if (ls->token == TK_not) {
op = BC_NOT;
} else if (ls->token == '-') {
op = BC_UNM;
} else if (ls->token == '#') {
op = BC_LEN;
} else {
expr_simple(ls, v);
return;
}
lj_lex_next(ls);
expr_binop(ls, v, UNARY_PRIORITY);
bcemit_unop(ls->fs, op, v);
}
/* Parse binary expressions with priority higher than the limit. */
static BinOpr expr_binop(LexState *ls, ExpDesc *v, uint32_t limit)
{
BinOpr op;
synlevel_begin(ls);
expr_unop(ls, v);
op = token2binop(ls->token);
while (op != OPR_NOBINOPR && priority[op].left > limit) {
ExpDesc v2;
BinOpr nextop;
lj_lex_next(ls);
bcemit_binop_left(ls->fs, op, v);
/* Parse binary expression with higher priority. */
nextop = expr_binop(ls, &v2, priority[op].right);
bcemit_binop(ls->fs, op, v, &v2);
op = nextop;
}
synlevel_end(ls);
return op; /* Return unconsumed binary operator (if any). */
}
/* Parse expression. */
static void expr(LexState *ls, ExpDesc *v)
{
expr_binop(ls, v, 0); /* Priority 0: parse whole expression. */
}
/* Assign expression to the next register. */
static void expr_next(LexState *ls)
{
ExpDesc e;
expr(ls, &e);
expr_tonextreg(ls->fs, &e);
}
/* Parse conditional expression. */
static BCPos expr_cond(LexState *ls)
{
ExpDesc v;
expr(ls, &v);
if (v.k == VKNIL) v.k = VKFALSE;
bcemit_branch_t(ls->fs, &v);
return v.f;
}
/* -- Assignments --------------------------------------------------------- */
/* List of LHS variables. */
typedef struct LHSVarList {
ExpDesc v; /* LHS variable. */
struct LHSVarList *prev; /* Link to previous LHS variable. */
} LHSVarList;
/* Eliminate write-after-read hazards for local variable assignment. */
static void assign_hazard(LexState *ls, LHSVarList *lh, const ExpDesc *v)
{
FuncState *fs = ls->fs;
BCReg reg = v->u.s.info; /* Check against this variable. */
BCReg tmp = fs->freereg; /* Rename to this temp. register (if needed). */
int hazard = 0;
for (; lh; lh = lh->prev) {
if (lh->v.k == VINDEXED) {
if (lh->v.u.s.info == reg) { /* t[i], t = 1, 2 */
hazard = 1;
lh->v.u.s.info = tmp;
}
if (lh->v.u.s.aux == reg) { /* t[i], i = 1, 2 */
hazard = 1;
lh->v.u.s.aux = tmp;
}
}
}
if (hazard) {
bcemit_AD(fs, BC_MOV, tmp, reg); /* Rename conflicting variable. */
bcreg_reserve(fs, 1);
}
}
/* Adjust LHS/RHS of an assignment. */
static void assign_adjust(LexState *ls, BCReg nvars, BCReg nexps, ExpDesc *e)
{
FuncState *fs = ls->fs;
int32_t extra = (int32_t)nvars - (int32_t)nexps;
if (e->k == VCALL) {
extra++; /* Compensate for the VCALL itself. */
if (extra < 0) extra = 0;
setbc_b(bcptr(fs, e), extra+1); /* Fixup call results. */
if (extra > 1) bcreg_reserve(fs, (BCReg)extra-1);
} else {
if (e->k != VVOID)
expr_tonextreg(fs, e); /* Close last expression. */
if (extra > 0) { /* Leftover LHS are set to nil. */
BCReg reg = fs->freereg;
bcreg_reserve(fs, (BCReg)extra);
bcemit_nil(fs, reg, (BCReg)extra);
}
}
}
/* Recursively parse assignment statement. */
static void parse_assignment(LexState *ls, LHSVarList *lh, BCReg nvars)
{
ExpDesc e;
checkcond(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED, LJ_ERR_XSYNTAX);
if (lex_opt(ls, ',')) { /* Collect LHS list and recurse upwards. */
LHSVarList vl;
vl.prev = lh;
expr_primary(ls, &vl.v);
if (vl.v.k == VLOCAL)
assign_hazard(ls, lh, &vl.v);
checklimit(ls->fs, ls->level + nvars, LJ_MAX_XLEVEL, "variable names");
parse_assignment(ls, &vl, nvars+1);
} else { /* Parse RHS. */
BCReg nexps;
lex_check(ls, '=');
nexps = expr_list(ls, &e);
if (nexps == nvars) {
if (e.k == VCALL) {
if (bc_op(*bcptr(ls->fs, &e)) == BC_VARG) { /* Vararg assignment. */
ls->fs->freereg--;
e.k = VRELOCABLE;
} else { /* Multiple call results. */
e.u.s.info = e.u.s.aux; /* Base of call is not relocatable. */
e.k = VNONRELOC;
}
}
bcemit_store(ls->fs, &lh->v, &e);
return;
}
assign_adjust(ls, nvars, nexps, &e);
if (nexps > nvars)
ls->fs->freereg -= nexps - nvars; /* Drop leftover regs. */
}
/* Assign RHS to LHS and recurse downwards. */
expr_init(&e, VNONRELOC, ls->fs->freereg-1);
bcemit_store(ls->fs, &lh->v, &e);
}
/* Parse call statement or assignment. */
static void parse_call_assign(LexState *ls)
{
FuncState *fs = ls->fs;
LHSVarList vl;
expr_primary(ls, &vl.v);
if (vl.v.k == VCALL) { /* Function call statement. */
setbc_b(bcptr(fs, &vl.v), 1); /* No results. */
} else { /* Start of an assignment. */
vl.prev = NULL;
parse_assignment(ls, &vl, 1);
}
}
/* Parse 'local' statement. */
static void parse_local(LexState *ls)
{
if (lex_opt(ls, TK_function)) { /* Local function declaration. */
ExpDesc v, b;
FuncState *fs = ls->fs;
var_new(ls, 0, lex_str(ls));
expr_init(&v, VLOCAL, fs->freereg);
v.u.s.aux = fs->varmap[fs->freereg];
bcreg_reserve(fs, 1);
var_add(ls, 1);
parse_body(ls, &b, 0, ls->linenumber);
/* bcemit_store(fs, &v, &b) without setting VSTACK_VAR_RW. */
expr_free(fs, &b);
expr_toreg(fs, &b, v.u.s.info);
/* The upvalue is in scope, but the local is only valid after the store. */
var_get(ls, fs, fs->nactvar - 1).startpc = fs->pc;
} else { /* Local variable declaration. */
ExpDesc e;
BCReg nexps, nvars = 0;
do { /* Collect LHS. */
var_new(ls, nvars++, lex_str(ls));
} while (lex_opt(ls, ','));
if (lex_opt(ls, '=')) { /* Optional RHS. */
nexps = expr_list(ls, &e);
} else { /* Or implicitly set to nil. */
e.k = VVOID;
nexps = 0;
}
assign_adjust(ls, nvars, nexps, &e);
var_add(ls, nvars);
}
}
/* Parse 'function' statement. */
static void parse_func(LexState *ls, BCLine line)
{
FuncState *fs;
ExpDesc v, b;
int needself = 0;
lj_lex_next(ls); /* Skip 'function'. */
/* Parse function name. */
var_lookup(ls, &v);
while (ls->token == '.') /* Multiple dot-separated fields. */
expr_field(ls, &v);
if (ls->token == ':') { /* Optional colon to signify method call. */
needself = 1;
expr_field(ls, &v);
}
parse_body(ls, &b, needself, line);
fs = ls->fs;
bcemit_store(fs, &v, &b);
fs->bcbase[fs->pc - 1].line = line; /* Set line for the store. */
}
/* -- Control transfer statements ----------------------------------------- */
/* Check for end of block. */
static int endofblock(LexToken token)
{
switch (token) {
case TK_else: case TK_elseif: case TK_end: case TK_until: case TK_eof:
return 1;
default:
return 0;
}
}
/* Parse 'return' statement. */
static void parse_return(LexState *ls)
{
BCIns ins;
FuncState *fs = ls->fs;
lj_lex_next(ls); /* Skip 'return'. */
fs->flags |= PROTO_HAS_RETURN;
if (endofblock(ls->token) || ls->token == ';') { /* Bare return. */
ins = BCINS_AD(BC_RET0, 0, 1);
} else { /* Return with one or more values. */
ExpDesc e; /* Receives the _last_ expression in the list. */
BCReg nret = expr_list(ls, &e);
if (nret == 1) { /* Return one result. */
if (e.k == VCALL) { /* Check for tail call. */
BCIns *ip = bcptr(fs, &e);
/* It doesn't pay off to add BC_VARGT just for 'return ...'. */
if (bc_op(*ip) == BC_VARG) goto notailcall;
fs->pc--;
ins = BCINS_AD(bc_op(*ip)-BC_CALL+BC_CALLT, bc_a(*ip), bc_c(*ip));
} else { /* Can return the result from any register. */
ins = BCINS_AD(BC_RET1, expr_toanyreg(fs, &e), 2);
}
} else {
if (e.k == VCALL) { /* Append all results from a call. */
notailcall:
setbc_b(bcptr(fs, &e), 0);
ins = BCINS_AD(BC_RETM, fs->nactvar, e.u.s.aux - fs->nactvar);
} else {
expr_tonextreg(fs, &e); /* Force contiguous registers. */
ins = BCINS_AD(BC_RET, fs->nactvar, nret+1);
}
}
}
if (fs->flags & PROTO_CHILD)
bcemit_AJ(fs, BC_UCLO, 0, 0); /* May need to close upvalues first. */
bcemit_INS(fs, ins);
}
/* Parse 'break' statement. */
static void parse_break(LexState *ls)
{
ls->fs->bl->flags |= FSCOPE_BREAK;
gola_new(ls, NAME_BREAK, VSTACK_GOTO, bcemit_jmp(ls->fs));
}
/* Parse 'goto' statement. */
static void parse_goto(LexState *ls)
{
FuncState *fs = ls->fs;
GCstr *name = lex_str(ls);
VarInfo *vl = gola_findlabel(ls, name);
if (vl) /* Treat backwards goto within same scope like a loop. */
bcemit_AJ(fs, BC_LOOP, vl->slot, -1); /* No BC range check. */
fs->bl->flags |= FSCOPE_GOLA;
gola_new(ls, name, VSTACK_GOTO, bcemit_jmp(fs));
}
/* Parse label. */
static void parse_label(LexState *ls)
{
FuncState *fs = ls->fs;
GCstr *name;
MSize idx;
fs->lasttarget = fs->pc;
fs->bl->flags |= FSCOPE_GOLA;
lj_lex_next(ls); /* Skip '::'. */
name = lex_str(ls);
if (gola_findlabel(ls, name))
lj_lex_error(ls, 0, LJ_ERR_XLDUP, strdata(name));
idx = gola_new(ls, name, VSTACK_LABEL, fs->pc);
lex_check(ls, TK_label);
/* Recursively parse trailing statements: labels and ';' (Lua 5.2 only). */
for (;;) {
if (ls->token == TK_label) {
synlevel_begin(ls);
parse_label(ls);
synlevel_end(ls);
} else if (LJ_52 && ls->token == ';') {
lj_lex_next(ls);
} else {
break;
}
}
/* Trailing label is considered to be outside of scope. */
if (endofblock(ls->token) && ls->token != TK_until)
ls->vstack[idx].slot = fs->bl->nactvar;
gola_resolve(ls, fs->bl, idx);
}
/* -- Blocks, loops and conditional statements ---------------------------- */
/* Parse a block. */
static void parse_block(LexState *ls)
{
FuncState *fs = ls->fs;
FuncScope bl;
fscope_begin(fs, &bl, 0);
parse_chunk(ls);
fscope_end(fs);
}
/* Parse 'while' statement. */
static void parse_while(LexState *ls, BCLine line)
{
FuncState *fs = ls->fs;
BCPos start, loop, condexit;
FuncScope bl;
lj_lex_next(ls); /* Skip 'while'. */
start = fs->lasttarget = fs->pc;
condexit = expr_cond(ls);
fscope_begin(fs, &bl, FSCOPE_LOOP);
lex_check(ls, TK_do);
loop = bcemit_AD(fs, BC_LOOP, fs->nactvar, 0);
parse_block(ls);
jmp_patch(fs, bcemit_jmp(fs), start);
lex_match(ls, TK_end, TK_while, line);
fscope_end(fs);
jmp_tohere(fs, condexit);
jmp_patchins(fs, loop, fs->pc);
}
/* Parse 'repeat' statement. */
static void parse_repeat(LexState *ls, BCLine line)
{
FuncState *fs = ls->fs;
BCPos loop = fs->lasttarget = fs->pc;
BCPos condexit;
FuncScope bl1, bl2;
fscope_begin(fs, &bl1, FSCOPE_LOOP); /* Breakable loop scope. */
fscope_begin(fs, &bl2, 0); /* Inner scope. */
lj_lex_next(ls); /* Skip 'repeat'. */
bcemit_AD(fs, BC_LOOP, fs->nactvar, 0);
parse_chunk(ls);
lex_match(ls, TK_until, TK_repeat, line);
condexit = expr_cond(ls); /* Parse condition (still inside inner scope). */
if (!(bl2.flags & FSCOPE_UPVAL)) { /* No upvalues? Just end inner scope. */
fscope_end(fs);
} else { /* Otherwise generate: cond: UCLO+JMP out, !cond: UCLO+JMP loop. */
parse_break(ls); /* Break from loop and close upvalues. */
jmp_tohere(fs, condexit);
fscope_end(fs); /* End inner scope and close upvalues. */
condexit = bcemit_jmp(fs);
}
jmp_patch(fs, condexit, loop); /* Jump backwards if !cond. */
jmp_patchins(fs, loop, fs->pc);
fscope_end(fs); /* End loop scope. */
}
/* Parse numeric 'for'. */
static void parse_for_num(LexState *ls, GCstr *varname, BCLine line)
{
FuncState *fs = ls->fs;
BCReg base = fs->freereg;
FuncScope bl;
BCPos loop, loopend;
/* Hidden control variables. */
var_new_fixed(ls, FORL_IDX, VARNAME_FOR_IDX);
var_new_fixed(ls, FORL_STOP, VARNAME_FOR_STOP);
var_new_fixed(ls, FORL_STEP, VARNAME_FOR_STEP);
/* Visible copy of index variable. */
var_new(ls, FORL_EXT, varname);
lex_check(ls, '=');
expr_next(ls);
lex_check(ls, ',');
expr_next(ls);
if (lex_opt(ls, ',')) {
expr_next(ls);
} else {
bcemit_AD(fs, BC_KSHORT, fs->freereg, 1); /* Default step is 1. */
bcreg_reserve(fs, 1);
}
var_add(ls, 3); /* Hidden control variables. */
lex_check(ls, TK_do);
loop = bcemit_AJ(fs, BC_FORI, base, NO_JMP);
fscope_begin(fs, &bl, 0); /* Scope for visible variables. */
var_add(ls, 1);
bcreg_reserve(fs, 1);
parse_block(ls);
fscope_end(fs);
/* Perform loop inversion. Loop control instructions are at the end. */
loopend = bcemit_AJ(fs, BC_FORL, base, NO_JMP);
fs->bcbase[loopend].line = line; /* Fix line for control ins. */
jmp_patchins(fs, loopend, loop+1);
jmp_patchins(fs, loop, fs->pc);
}
/* Try to predict whether the iterator is next() and specialize the bytecode.
** Detecting next() and pairs() by name is simplistic, but quite effective.
** The interpreter backs off if the check for the closure fails at runtime.
*/
static int predict_next(LexState *ls, FuncState *fs, BCPos pc)
{
BCIns ins = fs->bcbase[pc].ins;
GCstr *name;
cTValue *o;
switch (bc_op(ins)) {
case BC_MOV:
name = gco2str(gcref(var_get(ls, fs, bc_d(ins)).name));
break;
case BC_UGET:
name = gco2str(gcref(ls->vstack[fs->uvmap[bc_d(ins)]].name));
break;
case BC_GGET:
/* There's no inverse index (yet), so lookup the strings. */
o = lj_tab_getstr(fs->kt, lj_str_newlit(ls->L, "pairs"));
if (o && tvhaskslot(o) && tvkslot(o) == bc_d(ins))
return 1;
o = lj_tab_getstr(fs->kt, lj_str_newlit(ls->L, "next"));
if (o && tvhaskslot(o) && tvkslot(o) == bc_d(ins))
return 1;
return 0;
default:
return 0;
}
return (name->len == 5 && !strcmp(strdata(name), "pairs")) ||
(name->len == 4 && !strcmp(strdata(name), "next"));
}
/* Parse 'for' iterator. */
static void parse_for_iter(LexState *ls, GCstr *indexname)
{
FuncState *fs = ls->fs;
ExpDesc e;
BCReg nvars = 0;
BCLine line;
BCReg base = fs->freereg + 3;
BCPos loop, loopend, exprpc = fs->pc;
FuncScope bl;
int isnext;
/* Hidden control variables. */
var_new_fixed(ls, nvars++, VARNAME_FOR_GEN);
var_new_fixed(ls, nvars++, VARNAME_FOR_STATE);
var_new_fixed(ls, nvars++, VARNAME_FOR_CTL);
/* Visible variables returned from iterator. */
var_new(ls, nvars++, indexname);
while (lex_opt(ls, ','))
var_new(ls, nvars++, lex_str(ls));
lex_check(ls, TK_in);
line = ls->linenumber;
assign_adjust(ls, 3, expr_list(ls, &e), &e);
bcreg_bump(fs, 3); /* The iterator needs another 3 slots (func + 2 args). */
isnext = (nvars <= 5 && predict_next(ls, fs, exprpc));
var_add(ls, 3); /* Hidden control variables. */
lex_check(ls, TK_do);
loop = bcemit_AJ(fs, isnext ? BC_ISNEXT : BC_JMP, base, NO_JMP);
fscope_begin(fs, &bl, 0); /* Scope for visible variables. */
var_add(ls, nvars-3);
bcreg_reserve(fs, nvars-3);
parse_block(ls);
fscope_end(fs);
/* Perform loop inversion. Loop control instructions are at the end. */
jmp_patchins(fs, loop, fs->pc);
bcemit_ABC(fs, isnext ? BC_ITERN : BC_ITERC, base, nvars-3+1, 2+1);
loopend = bcemit_AJ(fs, BC_ITERL, base, NO_JMP);
fs->bcbase[loopend-1].line = line; /* Fix line for control ins. */
fs->bcbase[loopend].line = line;
jmp_patchins(fs, loopend, loop+1);
}
/* Parse 'for' statement. */
static void parse_for(LexState *ls, BCLine line)
{
FuncState *fs = ls->fs;
GCstr *varname;
FuncScope bl;
fscope_begin(fs, &bl, FSCOPE_LOOP);
lj_lex_next(ls); /* Skip 'for'. */
varname = lex_str(ls); /* Get first variable name. */
if (ls->token == '=')
parse_for_num(ls, varname, line);
else if (ls->token == ',' || ls->token == TK_in)
parse_for_iter(ls, varname);
else
err_syntax(ls, LJ_ERR_XFOR);
lex_match(ls, TK_end, TK_for, line);
fscope_end(fs); /* Resolve break list. */
}
/* Parse condition and 'then' block. */
static BCPos parse_then(LexState *ls)
{
BCPos condexit;
lj_lex_next(ls); /* Skip 'if' or 'elseif'. */
condexit = expr_cond(ls);
lex_check(ls, TK_then);
parse_block(ls);
return condexit;
}
/* Parse 'if' statement. */
static void parse_if(LexState *ls, BCLine line)
{
FuncState *fs = ls->fs;
BCPos flist;
BCPos escapelist = NO_JMP;
flist = parse_then(ls);
while (ls->token == TK_elseif) { /* Parse multiple 'elseif' blocks. */
jmp_append(fs, &escapelist, bcemit_jmp(fs));
jmp_tohere(fs, flist);
flist = parse_then(ls);
}
if (ls->token == TK_else) { /* Parse optional 'else' block. */
jmp_append(fs, &escapelist, bcemit_jmp(fs));
jmp_tohere(fs, flist);
lj_lex_next(ls); /* Skip 'else'. */
parse_block(ls);
} else {
jmp_append(fs, &escapelist, flist);
}
jmp_tohere(fs, escapelist);
lex_match(ls, TK_end, TK_if, line);
}
/* -- Parse statements ---------------------------------------------------- */
/* Parse a statement. Returns 1 if it must be the last one in a chunk. */
static int parse_stmt(LexState *ls)
{
BCLine line = ls->linenumber;
switch (ls->token) {
case TK_if:
parse_if(ls, line);
break;
case TK_while:
parse_while(ls, line);
break;
case TK_do:
lj_lex_next(ls);
parse_block(ls);
lex_match(ls, TK_end, TK_do, line);
break;
case TK_for:
parse_for(ls, line);
break;
case TK_repeat:
parse_repeat(ls, line);
break;
case TK_function:
parse_func(ls, line);
break;
case TK_local:
lj_lex_next(ls);
parse_local(ls);
break;
case TK_return:
parse_return(ls);
return 1; /* Must be last. */
case TK_break:
lj_lex_next(ls);
parse_break(ls);
return !LJ_52; /* Must be last in Lua 5.1. */
#if LJ_52
case ';':
lj_lex_next(ls);
break;
#endif
case TK_label:
parse_label(ls);
break;
case TK_goto:
if (LJ_52 || lj_lex_lookahead(ls) == TK_name) {
lj_lex_next(ls);
parse_goto(ls);
break;
} /* else: fallthrough */
default:
parse_call_assign(ls);
break;
}
return 0;
}
/* A chunk is a list of statements optionally separated by semicolons. */
static void parse_chunk(LexState *ls)
{
int islast = 0;
synlevel_begin(ls);
while (!islast && !endofblock(ls->token)) {
islast = parse_stmt(ls);
lex_opt(ls, ';');
lua_assert(ls->fs->framesize >= ls->fs->freereg &&
ls->fs->freereg >= ls->fs->nactvar);
ls->fs->freereg = ls->fs->nactvar; /* Free registers after each stmt. */
}
synlevel_end(ls);
}
/* Entry point of bytecode parser. */
GCproto *lj_parse(LexState *ls)
{
FuncState fs;
FuncScope bl;
GCproto *pt;
lua_State *L = ls->L;
#ifdef LUAJIT_DISABLE_DEBUGINFO
ls->chunkname = lj_str_newlit(L, "=");
#else
ls->chunkname = lj_str_newz(L, ls->chunkarg);
#endif
setstrV(L, L->top, ls->chunkname); /* Anchor chunkname string. */
incr_top(L);
ls->level = 0;
fs_init(ls, &fs);
fs.linedefined = 0;
fs.numparams = 0;
fs.bcbase = NULL;
fs.bclim = 0;
fs.flags |= PROTO_VARARG; /* Main chunk is always a vararg func. */
fscope_begin(&fs, &bl, 0);
bcemit_AD(&fs, BC_FUNCV, 0, 0); /* Placeholder. */
lj_lex_next(ls); /* Read-ahead first token. */
parse_chunk(ls);
if (ls->token != TK_eof)
err_token(ls, TK_eof);
pt = fs_finish(ls, ls->linenumber);
L->top--; /* Drop chunkname. */
lua_assert(fs.prev == NULL);
lua_assert(ls->fs == NULL);
lua_assert(pt->sizeuv == 0);
return pt;
}
|