summaryrefslogtreecommitdiffstats
path: root/src/spellsuggest.c
blob: b305bfb83e51380048537d050b9fcf574fa7ff73 (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
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
/* vi:set ts=8 sts=4 sw=4 noet:
 *
 * VIM - Vi IMproved	by Bram Moolenaar
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 * See README.txt for an overview of the Vim source code.
 */

/*
 * spellsuggest.c: functions for spelling suggestions
 */

#include "vim.h"

#if defined(FEAT_SPELL) || defined(PROTO)

/*
 * Use this to adjust the score after finding suggestions, based on the
 * suggested word sounding like the bad word.  This is much faster than doing
 * it for every possible suggestion.
 * Disadvantage: When "the" is typed as "hte" it sounds quite different ("@"
 * vs "ht") and goes down in the list.
 * Used when 'spellsuggest' is set to "best".
 */
#define RESCORE(word_score, sound_score) ((3 * (word_score) + (sound_score)) / 4)

/*
 * Do the opposite: based on a maximum end score and a known sound score,
 * compute the maximum word score that can be used.
 */
#define MAXSCORE(word_score, sound_score) ((4 * (word_score) - (sound_score)) / 3)

// only used for su_badflags
#define WF_MIXCAP   0x20	// mix of upper and lower case: macaRONI

/*
 * Information used when looking for suggestions.
 */
typedef struct suginfo_S
{
    garray_T	su_ga;		    // suggestions, contains "suggest_T"
    int		su_maxcount;	    // max. number of suggestions displayed
    int		su_maxscore;	    // maximum score for adding to su_ga
    int		su_sfmaxscore;	    // idem, for when doing soundfold words
    garray_T	su_sga;		    // like su_ga, sound-folded scoring
    char_u	*su_badptr;	    // start of bad word in line
    int		su_badlen;	    // length of detected bad word in line
    int		su_badflags;	    // caps flags for bad word
    char_u	su_badword[MAXWLEN]; // bad word truncated at su_badlen
    char_u	su_fbadword[MAXWLEN]; // su_badword case-folded
    char_u	su_sal_badword[MAXWLEN]; // su_badword soundfolded
    hashtab_T	su_banned;	    // table with banned words
    slang_T	*su_sallang;	    // default language for sound folding
} suginfo_T;

// One word suggestion.  Used in "si_ga".
typedef struct suggest_S
{
    char_u	*st_word;	// suggested word, allocated string
    int		st_wordlen;	// STRLEN(st_word)
    int		st_orglen;	// length of replaced text
    int		st_score;	// lower is better
    int		st_altscore;	// used when st_score compares equal
    int		st_salscore;	// st_score is for soundalike
    int		st_had_bonus;	// bonus already included in score
    slang_T	*st_slang;	// language used for sound folding
} suggest_T;

#define SUG(ga, i) (((suggest_T *)(ga).ga_data)[i])

// TRUE if a word appears in the list of banned words.
#define WAS_BANNED(su, word) (!HASHITEM_EMPTY(hash_find(&(su)->su_banned, word)))

// Number of suggestions kept when cleaning up.  We need to keep more than
// what is displayed, because when rescore_suggestions() is called the score
// may change and wrong suggestions may be removed later.
#define SUG_CLEAN_COUNT(su)    ((su)->su_maxcount < 130 ? 150 : (su)->su_maxcount + 20)

// Threshold for sorting and cleaning up suggestions.  Don't want to keep lots
// of suggestions that are not going to be displayed.
#define SUG_MAX_COUNT(su)	(SUG_CLEAN_COUNT(su) + 50)

// score for various changes
#define SCORE_SPLIT	149	// split bad word
#define SCORE_SPLIT_NO	249	// split bad word with NOSPLITSUGS
#define SCORE_ICASE	52	// slightly different case
#define SCORE_REGION	200	// word is for different region
#define SCORE_RARE	180	// rare word
#define SCORE_SWAP	75	// swap two characters
#define SCORE_SWAP3	110	// swap two characters in three
#define SCORE_REP	65	// REP replacement
#define SCORE_SUBST	93	// substitute a character
#define SCORE_SIMILAR	33	// substitute a similar character
#define SCORE_SUBCOMP	33	// substitute a composing character
#define SCORE_DEL	94	// delete a character
#define SCORE_DELDUP	66	// delete a duplicated character
#define SCORE_DELCOMP	28	// delete a composing character
#define SCORE_INS	96	// insert a character
#define SCORE_INSDUP	67	// insert a duplicate character
#define SCORE_INSCOMP	30	// insert a composing character
#define SCORE_NONWORD	103	// change non-word to word char

#define SCORE_FILE	30	// suggestion from a file
#define SCORE_MAXINIT	350	// Initial maximum score: higher == slower.
				// 350 allows for about three changes.

#define SCORE_COMMON1	30	// subtracted for words seen before
#define SCORE_COMMON2	40	// subtracted for words often seen
#define SCORE_COMMON3	50	// subtracted for words very often seen
#define SCORE_THRES2	10	// word count threshold for COMMON2
#define SCORE_THRES3	100	// word count threshold for COMMON3

// When trying changed soundfold words it becomes slow when trying more than
// two changes.  With less than two changes it's slightly faster but we miss a
// few good suggestions.  In rare cases we need to try three of four changes.
#define SCORE_SFMAX1	200	// maximum score for first try
#define SCORE_SFMAX2	300	// maximum score for second try
#define SCORE_SFMAX3	400	// maximum score for third try

#define SCORE_BIG	(SCORE_INS * 3)	// big difference
#define SCORE_MAXMAX	999999		// accept any score
#define SCORE_LIMITMAX	350		// for spell_edit_score_limit()

// for spell_edit_score_limit() we need to know the minimum value of
// SCORE_ICASE, SCORE_SWAP, SCORE_DEL, SCORE_SIMILAR and SCORE_INS
#define SCORE_EDIT_MIN	SCORE_SIMILAR

/*
 * For finding suggestions: At each node in the tree these states are tried:
 */
typedef enum
{
    STATE_START = 0,	// At start of node check for NUL bytes (goodword
			// ends); if badword ends there is a match, otherwise
			// try splitting word.
    STATE_NOPREFIX,	// try without prefix
    STATE_SPLITUNDO,	// Undo splitting.
    STATE_ENDNUL,	// Past NUL bytes at start of the node.
    STATE_PLAIN,	// Use each byte of the node.
    STATE_DEL,		// Delete a byte from the bad word.
    STATE_INS_PREP,	// Prepare for inserting bytes.
    STATE_INS,		// Insert a byte in the bad word.
    STATE_SWAP,		// Swap two bytes.
    STATE_UNSWAP,	// Undo swap two characters.
    STATE_SWAP3,	// Swap two characters over three.
    STATE_UNSWAP3,	// Undo Swap two characters over three.
    STATE_UNROT3L,	// Undo rotate three characters left
    STATE_UNROT3R,	// Undo rotate three characters right
    STATE_REP_INI,	// Prepare for using REP items.
    STATE_REP,		// Use matching REP items from the .aff file.
    STATE_REP_UNDO,	// Undo a REP item replacement.
    STATE_FINAL		// End of this node.
} state_T;

/*
 * Struct to keep the state at each level in suggest_try_change().
 */
typedef struct trystate_S
{
    state_T	ts_state;	// state at this level, STATE_
    int		ts_score;	// score
    idx_T	ts_arridx;	// index in tree array, start of node
    short	ts_curi;	// index in list of child nodes
    char_u	ts_fidx;	// index in fword[], case-folded bad word
    char_u	ts_fidxtry;	// ts_fidx at which bytes may be changed
    char_u	ts_twordlen;	// valid length of tword[]
    char_u	ts_prefixdepth;	// stack depth for end of prefix or
				// PFD_PREFIXTREE or PFD_NOPREFIX
    char_u	ts_flags;	// TSF_ flags
    char_u	ts_tcharlen;	// number of bytes in tword character
    char_u	ts_tcharidx;	// current byte index in tword character
    char_u	ts_isdiff;	// DIFF_ values
    char_u	ts_fcharstart;	// index in fword where badword char started
    char_u	ts_prewordlen;	// length of word in "preword[]"
    char_u	ts_splitoff;	// index in "tword" after last split
    char_u	ts_splitfidx;	// "ts_fidx" at word split
    char_u	ts_complen;	// nr of compound words used
    char_u	ts_compsplit;	// index for "compflags" where word was spit
    char_u	ts_save_badflags;   // su_badflags saved here
    char_u	ts_delidx;	// index in fword for char that was deleted,
				// valid when "ts_flags" has TSF_DIDDEL
} trystate_T;

// values for ts_isdiff
#define DIFF_NONE	0	// no different byte (yet)
#define DIFF_YES	1	// different byte found
#define DIFF_INSERT	2	// inserting character

// values for ts_flags
#define TSF_PREFIXOK	1	// already checked that prefix is OK
#define TSF_DIDSPLIT	2	// tried split at this point
#define TSF_DIDDEL	4	// did a delete, "ts_delidx" has index

// special values ts_prefixdepth
#define PFD_NOPREFIX	0xff	// not using prefixes
#define PFD_PREFIXTREE	0xfe	// walking through the prefix tree
#define PFD_NOTSPECIAL	0xfd	// highest value that's not special

static long spell_suggest_timeout = 5000;

static void spell_find_suggest(char_u *badptr, int badlen, suginfo_T *su, int maxcount, int banbadword, int need_cap, int interactive);
#ifdef FEAT_EVAL
static void spell_suggest_expr(suginfo_T *su, char_u *expr);
#endif
static void spell_suggest_file(suginfo_T *su, char_u *fname);
static void spell_suggest_intern(suginfo_T *su, int interactive);
static void spell_find_cleanup(suginfo_T *su);
static void suggest_try_special(suginfo_T *su);
static void suggest_try_change(suginfo_T *su);
static void suggest_trie_walk(suginfo_T *su, langp_T *lp, char_u *fword, int soundfold);
static void go_deeper(trystate_T *stack, int depth, int score_add);
static void find_keepcap_word(slang_T *slang, char_u *fword, char_u *kword);
static void score_comp_sal(suginfo_T *su);
static void score_combine(suginfo_T *su);
static int stp_sal_score(suggest_T *stp, suginfo_T *su, slang_T *slang, char_u *badsound);
static void suggest_try_soundalike_prep(void);
static void suggest_try_soundalike(suginfo_T *su);
static void suggest_try_soundalike_finish(void);
static void add_sound_suggest(suginfo_T *su, char_u *goodword, int score, langp_T *lp);
static int soundfold_find(slang_T *slang, char_u *word);
static int similar_chars(slang_T *slang, int c1, int c2);
static void add_suggestion(suginfo_T *su, garray_T *gap, char_u *goodword, int badlen, int score, int altscore, int had_bonus, slang_T *slang, int maxsf);
static void check_suggestions(suginfo_T *su, garray_T *gap);
static void add_banned(suginfo_T *su, char_u *word);
static void rescore_suggestions(suginfo_T *su);
static void rescore_one(suginfo_T *su, suggest_T *stp);
static int cleanup_suggestions(garray_T *gap, int maxscore, int keep);
static int soundalike_score(char_u *goodsound, char_u *badsound);
static int spell_edit_score(slang_T *slang, char_u *badword, char_u *goodword);
static int spell_edit_score_limit(slang_T *slang, char_u *badword, char_u *goodword, int limit);
static int spell_edit_score_limit_w(slang_T *slang, char_u *badword, char_u *goodword, int limit);

/*
 * Return TRUE when the sequence of flags in "compflags" plus "flag" can
 * possibly form a valid compounded word.  This also checks the COMPOUNDRULE
 * lines if they don't contain wildcards.
 */
    static int
can_be_compound(
    trystate_T	*sp,
    slang_T	*slang,
    char_u	*compflags,
    int		flag)
{
    // If the flag doesn't appear in sl_compstartflags or sl_compallflags
    // then it can't possibly compound.
    if (!byte_in_str(sp->ts_complen == sp->ts_compsplit
		? slang->sl_compstartflags : slang->sl_compallflags, flag))
	return FALSE;

    // If there are no wildcards, we can check if the flags collected so far
    // possibly can form a match with COMPOUNDRULE patterns.  This only
    // makes sense when we have two or more words.
    if (slang->sl_comprules != NULL && sp->ts_complen > sp->ts_compsplit)
    {
	int v;

	compflags[sp->ts_complen] = flag;
	compflags[sp->ts_complen + 1] = NUL;
	v = match_compoundrule(slang, compflags + sp->ts_compsplit);
	compflags[sp->ts_complen] = NUL;
	return v;
    }

    return TRUE;
}

/*
 * Adjust the score of common words.
 */
    static int
score_wordcount_adj(
    slang_T	*slang,
    int		score,
    char_u	*word,
    int		split)	    // word was split, less bonus
{
    hashitem_T	*hi;
    wordcount_T	*wc;
    int		bonus;
    int		newscore;

    hi = hash_find(&slang->sl_wordcount, word);
    if (HASHITEM_EMPTY(hi))
	return score;

    wc = HI2WC(hi);
    if (wc->wc_count < SCORE_THRES2)
	bonus = SCORE_COMMON1;
    else if (wc->wc_count < SCORE_THRES3)
	bonus = SCORE_COMMON2;
    else
	bonus = SCORE_COMMON3;
    if (split)
	newscore = score - bonus / 2;
    else
	newscore = score - bonus;
    if (newscore < 0)
	return 0;
    return newscore;
}

/*
 * Like captype() but for a KEEPCAP word add ONECAP if the word starts with a
 * capital.  So that make_case_word() can turn WOrd into Word.
 * Add ALLCAP for "WOrD".
 */
    static int
badword_captype(char_u *word, char_u *end)
{
    int		flags = captype(word, end);
    int		c;
    int		l, u;
    int		first;
    char_u	*p;

    if (!(flags & WF_KEEPCAP))
	return flags;

    // Count the number of UPPER and lower case letters.
    l = u = 0;
    first = FALSE;
    for (p = word; p < end; MB_PTR_ADV(p))
    {
	c = PTR2CHAR(p);
	if (SPELL_ISUPPER(c))
	{
	    ++u;
	    if (p == word)
		first = TRUE;
	}
	else
	    ++l;
    }

    // If there are more UPPER than lower case letters suggest an
    // ALLCAP word.  Otherwise, if the first letter is UPPER then
    // suggest ONECAP.  Exception: "ALl" most likely should be "All",
    // require three upper case letters.
    if (u > l && u > 2)
	flags |= WF_ALLCAP;
    else if (first)
	flags |= WF_ONECAP;

    if (u >= 2 && l >= 2)	// maCARONI maCAroni
	flags |= WF_MIXCAP;

    return flags;
}

/*
 * Opposite of offset2bytes().
 * "pp" points to the bytes and is advanced over it.
 * Returns the offset.
 */
    static int
bytes2offset(char_u **pp)
{
    char_u	*p = *pp;
    int		nr;
    int		c;

    c = *p++;
    if ((c & 0x80) == 0x00)		// 1 byte
    {
	nr = c - 1;
    }
    else if ((c & 0xc0) == 0x80)	// 2 bytes
    {
	nr = (c & 0x3f) - 1;
	nr = nr * 255 + (*p++ - 1);
    }
    else if ((c & 0xe0) == 0xc0)	// 3 bytes
    {
	nr = (c & 0x1f) - 1;
	nr = nr * 255 + (*p++ - 1);
	nr = nr * 255 + (*p++ - 1);
    }
    else				// 4 bytes
    {
	nr = (c & 0x0f) - 1;
	nr = nr * 255 + (*p++ - 1);
	nr = nr * 255 + (*p++ - 1);
	nr = nr * 255 + (*p++ - 1);
    }

    *pp = p;
    return nr;
}

// values for sps_flags
#define SPS_BEST    1
#define SPS_FAST    2
#define SPS_DOUBLE  4

static int sps_flags = SPS_BEST;	// flags from 'spellsuggest'
static int sps_limit = 9999;		// max nr of suggestions given

/*
 * Check the 'spellsuggest' option.  Return FAIL if it's wrong.
 * Sets "sps_flags" and "sps_limit".
 */
    int
spell_check_sps(void)
{
    char_u	*p;
    char_u	*s;
    char_u	buf[MAXPATHL];
    int		f;

    sps_flags = 0;
    sps_limit = 9999;

    for (p = p_sps; *p != NUL; )
    {
	copy_option_part(&p, buf, MAXPATHL, ",");

	f = 0;
	if (VIM_ISDIGIT(*buf))
	{
	    s = buf;
	    sps_limit = getdigits(&s);
	    if (*s != NUL && !VIM_ISDIGIT(*s))
		f = -1;
	}
	// Note: Keep this in sync with p_sps_values.
	else if (STRCMP(buf, "best") == 0)
	    f = SPS_BEST;
	else if (STRCMP(buf, "fast") == 0)
	    f = SPS_FAST;
	else if (STRCMP(buf, "double") == 0)
	    f = SPS_DOUBLE;
	else if (STRNCMP(buf, "expr:", 5) != 0
		&& STRNCMP(buf, "file:", 5) != 0
		&& (STRNCMP(buf, "timeout:", 8) != 0
		    || (!VIM_ISDIGIT(buf[8])
				  && !(buf[8] == '-' && VIM_ISDIGIT(buf[9])))))
	    f = -1;

	if (f == -1 || (sps_flags != 0 && f != 0))
	{
	    sps_flags = SPS_BEST;
	    sps_limit = 9999;
	    return FAIL;
	}
	if (f != 0)
	    sps_flags = f;
    }

    if (sps_flags == 0)
	sps_flags = SPS_BEST;

    return OK;
}

/*
 * "z=": Find badly spelled word under or after the cursor.
 * Give suggestions for the properly spelled word.
 * In Visual mode use the highlighted word as the bad word.
 * When "count" is non-zero use that suggestion.
 */
    void
spell_suggest(int count)
{
    char_u	*line;
    pos_T	prev_cursor = curwin->w_cursor;
    char_u	wcopy[MAXWLEN + 2];
    char_u	*p;
    int		i;
    int		c;
    suginfo_T	sug;
    suggest_T	*stp;
    int		mouse_used;
    int		need_cap;
    int		limit;
    int		selected = count;
    int		badlen = 0;
    int		msg_scroll_save = msg_scroll;
    int		wo_spell_save = curwin->w_p_spell;

    if (!curwin->w_p_spell)
    {
	parse_spelllang(curwin);
	curwin->w_p_spell = TRUE;
    }

    if (*curwin->w_s->b_p_spl == NUL)
    {
	emsg(_(e_spell_checking_is_not_possible));
	return;
    }

    if (VIsual_active)
    {
	// Use the Visually selected text as the bad word.  But reject
	// a multi-line selection.
	if (curwin->w_cursor.lnum != VIsual.lnum)
	{
	    vim_beep(BO_SPELL);
	    return;
	}
	badlen = (int)curwin->w_cursor.col - (int)VIsual.col;
	if (badlen < 0)
	    badlen = -badlen;
	else
	    curwin->w_cursor.col = VIsual.col;
	++badlen;
	end_visual_mode();
	// make sure we don't include the NUL at the end of the line
	if (badlen > ml_get_curline_len() - (int)curwin->w_cursor.col)
	    badlen = ml_get_curline_len() - (int)curwin->w_cursor.col;
    }
    // Find the start of the badly spelled word.
    else if (spell_move_to(curwin, FORWARD, SMT_ALL, TRUE, NULL) == 0
	    || curwin->w_cursor.col > prev_cursor.col)
    {
	// No bad word or it starts after the cursor: use the word under the
	// cursor.
	curwin->w_cursor = prev_cursor;
	line = ml_get_curline();
	p = line + curwin->w_cursor.col;
	// Backup to before start of word.
	while (p > line && spell_iswordp_nmw(p, curwin))
	    MB_PTR_BACK(line, p);
	// Forward to start of word.
	while (*p != NUL && !spell_iswordp_nmw(p, curwin))
	    MB_PTR_ADV(p);

	if (!spell_iswordp_nmw(p, curwin))		// No word found.
	{
	    beep_flush();
	    return;
	}
	curwin->w_cursor.col = (colnr_T)(p - line);
    }

    // Get the word and its length.

    // Figure out if the word should be capitalised.
    need_cap = check_need_cap(curwin, curwin->w_cursor.lnum,
							curwin->w_cursor.col);

    // Make a copy of current line since autocommands may free the line.
    line = vim_strnsave(ml_get_curline(), ml_get_curline_len());
    if (line == NULL)
	goto skip;

    // Get the list of suggestions.  Limit to 'lines' - 2 or the number in
    // 'spellsuggest', whatever is smaller.
    if (sps_limit > (int)Rows - 2)
	limit = (int)Rows - 2;
    else
	limit = sps_limit;
    spell_find_suggest(line + curwin->w_cursor.col, badlen, &sug, limit,
							TRUE, need_cap, TRUE);

    if (sug.su_ga.ga_len == 0)
	msg(_("Sorry, no suggestions"));
    else if (count > 0)
    {
	if (count > sug.su_ga.ga_len)
	    smsg(_("Sorry, only %ld suggestions"), (long)sug.su_ga.ga_len);
    }
    else
    {
#ifdef FEAT_RIGHTLEFT
	// When 'rightleft' is set the list is drawn right-left.
	cmdmsg_rl = curwin->w_p_rl;
	if (cmdmsg_rl)
	    msg_col = Columns - 1;
#endif

	// List the suggestions.
	msg_start();
	msg_row = Rows - 1;	// for when 'cmdheight' > 1
	lines_left = Rows;	// avoid more prompt
	vim_snprintf((char *)IObuff, IOSIZE, _("Change \"%.*s\" to:"),
						sug.su_badlen, sug.su_badptr);
#ifdef FEAT_RIGHTLEFT
	if (cmdmsg_rl && STRNCMP(IObuff, "Change", 6) == 0)
	{
	    // And now the rabbit from the high hat: Avoid showing the
	    // untranslated message rightleft.
	    vim_snprintf((char *)IObuff, IOSIZE, ":ot \"%.*s\" egnahC",
						sug.su_badlen, sug.su_badptr);
	}
#endif
	msg_puts((char *)IObuff);
	msg_clr_eos();
	msg_putchar('\n');

	msg_scroll = TRUE;
	for (i = 0; i < sug.su_ga.ga_len; ++i)
	{
	    int el;

	    stp = &SUG(sug.su_ga, i);

	    // The suggested word may replace only part of the bad word, add
	    // the not replaced part.  But only when it's not getting too long.
	    vim_strncpy(wcopy, stp->st_word, MAXWLEN);
	    el = sug.su_badlen - stp->st_orglen;
	    if (el > 0 && stp->st_wordlen + el <= MAXWLEN)
		vim_strncpy(wcopy + stp->st_wordlen,
					   sug.su_badptr + stp->st_orglen, el);
	    vim_snprintf((char *)IObuff, IOSIZE, "%2d", i + 1);
#ifdef FEAT_RIGHTLEFT
	    if (cmdmsg_rl)
		rl_mirror(IObuff);
#endif
	    msg_puts((char *)IObuff);

	    vim_snprintf((char *)IObuff, IOSIZE, " \"%s\"", wcopy);
	    msg_puts((char *)IObuff);

	    // The word may replace more than "su_badlen".
	    if (sug.su_badlen < stp->st_orglen)
	    {
		vim_snprintf((char *)IObuff, IOSIZE, _(" < \"%.*s\""),
					       stp->st_orglen, sug.su_badptr);
		msg_puts((char *)IObuff);
	    }

	    if (p_verbose > 0)
	    {
		// Add the score.
		if (sps_flags & (SPS_DOUBLE | SPS_BEST))
		    vim_snprintf((char *)IObuff, IOSIZE, " (%s%d - %d)",
			stp->st_salscore ? "s " : "",
			stp->st_score, stp->st_altscore);
		else
		    vim_snprintf((char *)IObuff, IOSIZE, " (%d)",
			    stp->st_score);
#ifdef FEAT_RIGHTLEFT
		if (cmdmsg_rl)
		    // Mirror the numbers, but keep the leading space.
		    rl_mirror(IObuff + 1);
#endif
		msg_advance(30);
		msg_puts((char *)IObuff);
	    }
	    msg_putchar('\n');
	}

#ifdef FEAT_RIGHTLEFT
	cmdmsg_rl = FALSE;
	msg_col = 0;
#endif
	// Ask for choice.
	selected = prompt_for_number(&mouse_used);
	if (mouse_used)
	    selected -= lines_left;
	lines_left = Rows;		// avoid more prompt
	// don't delay for 'smd' in normal_cmd()
	msg_scroll = msg_scroll_save;
    }

    if (selected > 0 && selected <= sug.su_ga.ga_len && u_save_cursor() == OK)
    {
	// Save the from and to text for :spellrepall.
	VIM_CLEAR(repl_from);
	VIM_CLEAR(repl_to);

	stp = &SUG(sug.su_ga, selected - 1);
	if (sug.su_badlen > stp->st_orglen)
	{
	    // Replacing less than "su_badlen", append the remainder to
	    // repl_to.
	    repl_from = vim_strnsave(sug.su_badptr, sug.su_badlen);
	    vim_snprintf((char *)IObuff, IOSIZE, "%s%.*s", stp->st_word,
		    sug.su_badlen - stp->st_orglen,
					      sug.su_badptr + stp->st_orglen);
	    repl_to = vim_strsave(IObuff);
	}
	else
	{
	    // Replacing su_badlen or more, use the whole word.
	    repl_from = vim_strnsave(sug.su_badptr, stp->st_orglen);
	    repl_to = vim_strsave(stp->st_word);
	}

	// Replace the word.
	p = alloc(STRLEN(line) - stp->st_orglen + stp->st_wordlen + 1);
	if (p != NULL)
	{
	    int len_diff = stp->st_wordlen - stp->st_orglen;

	    c = (int)(sug.su_badptr - line);
	    mch_memmove(p, line, c);
	    STRCPY(p + c, stp->st_word);
	    STRCAT(p, sug.su_badptr + stp->st_orglen);

	    // For redo we use a change-word command.
	    ResetRedobuff();
	    AppendToRedobuff((char_u *)"ciw");
	    AppendToRedobuffLit(p + c,
			    stp->st_wordlen + sug.su_badlen - stp->st_orglen);
	    AppendCharToRedobuff(ESC);

	    // "p" may be freed here
	    ml_replace(curwin->w_cursor.lnum, p, FALSE);
	    curwin->w_cursor.col = c;

	    changed_bytes(curwin->w_cursor.lnum, c);
#if defined(FEAT_PROP_POPUP)
	    if (curbuf->b_has_textprop && len_diff != 0)
		adjust_prop_columns(curwin->w_cursor.lnum, c, len_diff,
							       APC_SUBSTITUTE);
#endif
	}
    }
    else
	curwin->w_cursor = prev_cursor;

    spell_find_cleanup(&sug);
skip:
    vim_free(line);
    curwin->w_p_spell = wo_spell_save;
}

/*
 * Find spell suggestions for "word".  Return them in the growarray "*gap" as
 * a list of allocated strings.
 */
    void
spell_suggest_list(
    garray_T	*gap,
    char_u	*word,
    int		maxcount,	// maximum nr of suggestions
    int		need_cap,	// 'spellcapcheck' matched
    int		interactive)
{
    suginfo_T	sug;
    int		i;
    suggest_T	*stp;
    char_u	*wcopy;

    spell_find_suggest(word, 0, &sug, maxcount, FALSE, need_cap, interactive);

    // Make room in "gap".
    ga_init2(gap, sizeof(char_u *), sug.su_ga.ga_len + 1);
    if (ga_grow(gap, sug.su_ga.ga_len) == OK)
    {
	for (i = 0; i < sug.su_ga.ga_len; ++i)
	{
	    stp = &SUG(sug.su_ga, i);

	    // The suggested word may replace only part of "word", add the not
	    // replaced part.
	    wcopy = alloc(stp->st_wordlen
		      + (unsigned)STRLEN(sug.su_badptr + stp->st_orglen) + 1);
	    if (wcopy == NULL)
		break;
	    STRCPY(wcopy, stp->st_word);
	    STRCPY(wcopy + stp->st_wordlen, sug.su_badptr + stp->st_orglen);
	    ((char_u **)gap->ga_data)[gap->ga_len++] = wcopy;
	}
    }

    spell_find_cleanup(&sug);
}

/*
 * Find spell suggestions for the word at the start of "badptr".
 * Return the suggestions in "su->su_ga".
 * The maximum number of suggestions is "maxcount".
 * Note: does use info for the current window.
 * This is based on the mechanisms of Aspell, but completely reimplemented.
 */
    static void
spell_find_suggest(
    char_u	*badptr,
    int		badlen,		// length of bad word or 0 if unknown
    suginfo_T	*su,
    int		maxcount,
    int		banbadword,	// don't include badword in suggestions
    int		need_cap,	// word should start with capital
    int		interactive)
{
    hlf_T	attr = HLF_COUNT;
    char_u	buf[MAXPATHL];
    char_u	*p;
    int		do_combine = FALSE;
    char_u	*sps_copy;
#ifdef FEAT_EVAL
    static int	expr_busy = FALSE;
#endif
    int		c;
    int		i;
    langp_T	*lp;
    int		did_intern = FALSE;

    // Set the info in "*su".
    CLEAR_POINTER(su);
    ga_init2(&su->su_ga, sizeof(suggest_T), 10);
    ga_init2(&su->su_sga, sizeof(suggest_T), 10);
    if (*badptr == NUL)
	return;
    hash_init(&su->su_banned);

    su->su_badptr = badptr;
    if (badlen != 0)
	su->su_badlen = badlen;
    else
	su->su_badlen = spell_check(curwin, su->su_badptr, &attr, NULL, FALSE);
    su->su_maxcount = maxcount;
    su->su_maxscore = SCORE_MAXINIT;

    if (su->su_badlen >= MAXWLEN)
	su->su_badlen = MAXWLEN - 1;	// just in case
    vim_strncpy(su->su_badword, su->su_badptr, su->su_badlen);
    (void)spell_casefold(curwin, su->su_badptr, su->su_badlen,
						    su->su_fbadword, MAXWLEN);
    // TODO: make this work if the case-folded text is longer than the original
    // text. Currently an illegal byte causes wrong pointer computations.
    su->su_fbadword[su->su_badlen] = NUL;

    // get caps flags for bad word
    su->su_badflags = badword_captype(su->su_badptr,
					       su->su_badptr + su->su_badlen);
    if (need_cap)
	su->su_badflags |= WF_ONECAP;

    // Find the default language for sound folding.  We simply use the first
    // one in 'spelllang' that supports sound folding.  That's good for when
    // using multiple files for one language, it's not that bad when mixing
    // languages (e.g., "pl,en").
    for (i = 0; i < curbuf->b_s.b_langp.ga_len; ++i)
    {
	lp = LANGP_ENTRY(curbuf->b_s.b_langp, i);
	if (lp->lp_sallang != NULL)
	{
	    su->su_sallang = lp->lp_sallang;
	    break;
	}
    }

    // Soundfold the bad word with the default sound folding, so that we don't
    // have to do this many times.
    if (su->su_sallang != NULL)
	spell_soundfold(su->su_sallang, su->su_fbadword, TRUE,
							  su->su_sal_badword);

    // If the word is not capitalised and spell_check() doesn't consider the
    // word to be bad then it might need to be capitalised.  Add a suggestion
    // for that.
    c = PTR2CHAR(su->su_badptr);
    if (!SPELL_ISUPPER(c) && attr == HLF_COUNT)
    {
	make_case_word(su->su_badword, buf, WF_ONECAP);
	add_suggestion(su, &su->su_ga, buf, su->su_badlen, SCORE_ICASE,
					      0, TRUE, su->su_sallang, FALSE);
    }

    // Ban the bad word itself.  It may appear in another region.
    if (banbadword)
	add_banned(su, su->su_badword);

    // Make a copy of 'spellsuggest', because the expression may change it.
    sps_copy = vim_strsave(p_sps);
    if (sps_copy == NULL)
	return;
    spell_suggest_timeout = 5000;

    // Loop over the items in 'spellsuggest'.
    for (p = sps_copy; *p != NUL; )
    {
	copy_option_part(&p, buf, MAXPATHL, ",");

	if (STRNCMP(buf, "expr:", 5) == 0)
	{
#ifdef FEAT_EVAL
	    // Evaluate an expression.  Skip this when called recursively,
	    // when using spellsuggest() in the expression.
	    if (!expr_busy)
	    {
		expr_busy = TRUE;
		spell_suggest_expr(su, buf + 5);
		expr_busy = FALSE;
	    }
#endif
	}
	else if (STRNCMP(buf, "file:", 5) == 0)
	    // Use list of suggestions in a file.
	    spell_suggest_file(su, buf + 5);
	else if (STRNCMP(buf, "timeout:", 8) == 0)
	    // Limit the time searching for suggestions.
	    spell_suggest_timeout = atol((char *)buf + 8);
	else if (!did_intern)
	{
	    // Use internal method once.
	    spell_suggest_intern(su, interactive);
	    if (sps_flags & SPS_DOUBLE)
		do_combine = TRUE;
	    did_intern = TRUE;
	}
    }

    vim_free(sps_copy);

    if (do_combine)
	// Combine the two list of suggestions.  This must be done last,
	// because sorting changes the order again.
	score_combine(su);
}

#ifdef FEAT_EVAL
/*
 * Find suggestions by evaluating expression "expr".
 */
    static void
spell_suggest_expr(suginfo_T *su, char_u *expr)
{
    list_T	*list;
    listitem_T	*li;
    int		score;
    char_u	*p;

    // The work is split up in a few parts to avoid having to export
    // suginfo_T.
    // First evaluate the expression and get the resulting list.
    list = eval_spell_expr(su->su_badword, expr);
    if (list != NULL)
    {
	// Loop over the items in the list.
	FOR_ALL_LIST_ITEMS(list, li)
	    if (li->li_tv.v_type == VAR_LIST)
	    {
		// Get the word and the score from the items.
		score = get_spellword(li->li_tv.vval.v_list, &p);
		if (score >= 0 && score <= su->su_maxscore)
		    add_suggestion(su, &su->su_ga, p, su->su_badlen,
				       score, 0, TRUE, su->su_sallang, FALSE);
	    }
	list_unref(list);
    }

    // Remove bogus suggestions, sort and truncate at "maxcount".
    check_suggestions(su, &su->su_ga);
    (void)cleanup_suggestions(&su->su_ga, su->su_maxscore, su->su_maxcount);
}
#endif

/*
 * Find suggestions in file "fname".  Used for "file:" in 'spellsuggest'.
 */
    static void
spell_suggest_file(suginfo_T *su, char_u *fname)
{
    FILE	*fd;
    char_u	line[MAXWLEN * 2];
    char_u	*p;
    int		len;
    char_u	cword[MAXWLEN];

    // Open the file.
    fd = mch_fopen((char *)fname, "r");
    if (fd == NULL)
    {
	semsg(_(e_cant_open_file_str), fname);
	return;
    }

    // Read it line by line.
    while (!vim_fgets(line, MAXWLEN * 2, fd) && !got_int)
    {
	line_breakcheck();

	p = vim_strchr(line, '/');
	if (p == NULL)
	    continue;	    // No Tab found, just skip the line.
	*p++ = NUL;
	if (STRICMP(su->su_badword, line) == 0)
	{
	    // Match!  Isolate the good word, until CR or NL.
	    for (len = 0; p[len] >= ' '; ++len)
		;
	    p[len] = NUL;

	    // If the suggestion doesn't have specific case duplicate the case
	    // of the bad word.
	    if (captype(p, NULL) == 0)
	    {
		make_case_word(p, cword, su->su_badflags);
		p = cword;
	    }

	    add_suggestion(su, &su->su_ga, p, su->su_badlen,
				  SCORE_FILE, 0, TRUE, su->su_sallang, FALSE);
	}
    }

    fclose(fd);

    // Remove bogus suggestions, sort and truncate at "maxcount".
    check_suggestions(su, &su->su_ga);
    (void)cleanup_suggestions(&su->su_ga, su->su_maxscore, su->su_maxcount);
}

/*
 * Find suggestions for the internal method indicated by "sps_flags".
 */
    static void
spell_suggest_intern(suginfo_T *su, int interactive)
{
    // Load the .sug file(s) that are available and not done yet.
    suggest_load_files();

    // 1. Try special cases, such as repeating a word: "the the" -> "the".
    //
    // Set a maximum score to limit the combination of operations that is
    // tried.
    suggest_try_special(su);

    // 2. Try inserting/deleting/swapping/changing a letter, use REP entries
    //    from the .aff file and inserting a space (split the word).
    suggest_try_change(su);

    // For the resulting top-scorers compute the sound-a-like score.
    if (sps_flags & SPS_DOUBLE)
	score_comp_sal(su);

    // 3. Try finding sound-a-like words.
    if ((sps_flags & SPS_FAST) == 0)
    {
	if (sps_flags & SPS_BEST)
	    // Adjust the word score for the suggestions found so far for how
	    // they sound like.
	    rescore_suggestions(su);

	// While going through the soundfold tree "su_maxscore" is the score
	// for the soundfold word, limits the changes that are being tried,
	// and "su_sfmaxscore" the rescored score, which is set by
	// cleanup_suggestions().
	// First find words with a small edit distance, because this is much
	// faster and often already finds the top-N suggestions.  If we didn't
	// find many suggestions try again with a higher edit distance.
	// "sl_sounddone" is used to avoid doing the same word twice.
	suggest_try_soundalike_prep();
	su->su_maxscore = SCORE_SFMAX1;
	su->su_sfmaxscore = SCORE_MAXINIT * 3;
	suggest_try_soundalike(su);
	if (su->su_ga.ga_len < SUG_CLEAN_COUNT(su))
	{
	    // We didn't find enough matches, try again, allowing more
	    // changes to the soundfold word.
	    su->su_maxscore = SCORE_SFMAX2;
	    suggest_try_soundalike(su);
	    if (su->su_ga.ga_len < SUG_CLEAN_COUNT(su))
	    {
		// Still didn't find enough matches, try again, allowing even
		// more changes to the soundfold word.
		su->su_maxscore = SCORE_SFMAX3;
		suggest_try_soundalike(su);
	    }
	}
	su->su_maxscore = su->su_sfmaxscore;
	suggest_try_soundalike_finish();
    }

    // When CTRL-C was hit while searching do show the results.  Only clear
    // got_int when using a command, not for spellsuggest().
    ui_breakcheck();
    if (interactive && got_int)
    {
	(void)vgetc();
	got_int = FALSE;
    }

    if ((sps_flags & SPS_DOUBLE) == 0 && su->su_ga.ga_len != 0)
    {
	if (sps_flags & SPS_BEST)
	    // Adjust the word score for how it sounds like.
	    rescore_suggestions(su);

	// Remove bogus suggestions, sort and truncate at "maxcount".
	check_suggestions(su, &su->su_ga);
	(void)cleanup_suggestions(&su->su_ga, su->su_maxscore, su->su_maxcount);
    }
}

/*
 * Free the info put in "*su" by spell_find_suggest().
 */
    static void
spell_find_cleanup(suginfo_T *su)
{
    int		i;

    // Free the suggestions.
    for (i = 0; i < su->su_ga.ga_len; ++i)
	vim_free(SUG(su->su_ga, i).st_word);
    ga_clear(&su->su_ga);
    for (i = 0; i < su->su_sga.ga_len; ++i)
	vim_free(SUG(su->su_sga, i).st_word);
    ga_clear(&su->su_sga);

    // Free the banned words.
    hash_clear_all(&su->su_banned, 0);
}

/*
 * Try finding suggestions by recognizing specific situations.
 */
    static void
suggest_try_special(suginfo_T *su)
{
    char_u	*p;
    size_t	len;
    int		c;
    char_u	word[MAXWLEN];

    // Recognize a word that is repeated: "the the".
    p = skiptowhite(su->su_fbadword);
    len = p - su->su_fbadword;
    p = skipwhite(p);
    if (STRLEN(p) == len && STRNCMP(su->su_fbadword, p, len) == 0)
    {
	// Include badflags: if the badword is onecap or allcap
	// use that for the goodword too: "The the" -> "The".
	c = su->su_fbadword[len];
	su->su_fbadword[len] = NUL;
	make_case_word(su->su_fbadword, word, su->su_badflags);
	su->su_fbadword[len] = c;

	// Give a soundalike score of 0, compute the score as if deleting one
	// character.
	add_suggestion(su, &su->su_ga, word, su->su_badlen,
		       RESCORE(SCORE_REP, 0), 0, TRUE, su->su_sallang, FALSE);
    }
}

/*
 * Change the 0 to 1 to measure how much time is spent in each state.
 * Output is dumped in "suggestprof".
 */
#if 0
# define SUGGEST_PROFILE
proftime_T current;
proftime_T total;
proftime_T times[STATE_FINAL + 1];
long counts[STATE_FINAL + 1];

    static void
prof_init(void)
{
    for (int i = 0; i <= STATE_FINAL; ++i)
    {
	profile_zero(&times[i]);
	counts[i] = 0;
    }
    profile_start(&current);
    profile_start(&total);
}

// call before changing state
    static void
prof_store(state_T state)
{
    profile_end(&current);
    profile_add(&times[state], &current);
    ++counts[state];
    profile_start(&current);
}
# define PROF_STORE(state) prof_store(state);

    static void
prof_report(char *name)
{
    FILE *fd = fopen("suggestprof", "a");

    profile_end(&total);
    fprintf(fd, "-----------------------\n");
    fprintf(fd, "%s: %s\n", name, profile_msg(&total));
    for (int i = 0; i <= STATE_FINAL; ++i)
	fprintf(fd, "%d: %s (%ld)\n", i, profile_msg(&times[i]), counts[i]);
    fclose(fd);
}
#else
# define PROF_STORE(state)
#endif

/*
 * Try finding suggestions by adding/removing/swapping letters.
 */
    static void
suggest_try_change(suginfo_T *su)
{
    char_u	fword[MAXWLEN];	    // copy of the bad word, case-folded
    int		n;
    char_u	*p;
    int		lpi;
    langp_T	*lp;

    // We make a copy of the case-folded bad word, so that we can modify it
    // to find matches (esp. REP items).  Append some more text, changing
    // chars after the bad word may help.
    STRCPY(fword, su->su_fbadword);
    n = (int)STRLEN(fword);
    p = su->su_badptr + su->su_badlen;
    (void)spell_casefold(curwin, p, (int)STRLEN(p), fword + n, MAXWLEN - n);

    // Make sure the resulting text is not longer than the original text.
    n = (int)STRLEN(su->su_badptr);
    if (n < MAXWLEN)
	fword[n] = NUL;

    for (lpi = 0; lpi < curwin->w_s->b_langp.ga_len; ++lpi)
    {
	lp = LANGP_ENTRY(curwin->w_s->b_langp, lpi);

	// If reloading a spell file fails it's still in the list but
	// everything has been cleared.
	if (lp->lp_slang->sl_fbyts == NULL)
	    continue;

	// Try it for this language.  Will add possible suggestions.
#ifdef SUGGEST_PROFILE
	prof_init();
#endif
	suggest_trie_walk(su, lp, fword, FALSE);
#ifdef SUGGEST_PROFILE
	prof_report("try_change");
#endif
    }
}

// Check the maximum score, if we go over it we won't try this change.
#define TRY_DEEPER(su, stack, depth, add) \
       ((depth) < MAXWLEN - 1 && (stack)[depth].ts_score + (add) < (su)->su_maxscore)

/*
 * Try finding suggestions by adding/removing/swapping letters.
 *
 * This uses a state machine.  At each node in the tree we try various
 * operations.  When trying if an operation works "depth" is increased and the
 * stack[] is used to store info.  This allows combinations, thus insert one
 * character, replace one and delete another.  The number of changes is
 * limited by su->su_maxscore.
 *
 * After implementing this I noticed an article by Kemal Oflazer that
 * describes something similar: "Error-tolerant Finite State Recognition with
 * Applications to Morphological Analysis and Spelling Correction" (1996).
 * The implementation in the article is simplified and requires a stack of
 * unknown depth.  The implementation here only needs a stack depth equal to
 * the length of the word.
 *
 * This is also used for the sound-folded word, "soundfold" is TRUE then.
 * The mechanism is the same, but we find a match with a sound-folded word
 * that comes from one or more original words.  Each of these words may be
 * added, this is done by add_sound_suggest().
 * Don't use:
 *	the prefix tree or the keep-case tree
 *	"su->su_badlen"
 *	anything to do with upper and lower case
 *	anything to do with word or non-word characters ("spell_iswordp()")
 *	banned words
 *	word flags (rare, region, compounding)
 *	word splitting for now
 *	"similar_chars()"
 *	use "slang->sl_repsal" instead of "lp->lp_replang->sl_rep"
 */
    static void
suggest_trie_walk(
    suginfo_T	*su,
    langp_T	*lp,
    char_u	*fword,
    int		soundfold)
{
    char_u	tword[MAXWLEN];	    // good word collected so far
    trystate_T	stack[MAXWLEN];
    char_u	preword[MAXWLEN * 3]; // word found with proper case;
				      // concatenation of prefix compound
				      // words and split word.  NUL terminated
				      // when going deeper but not when coming
				      // back.
    char_u	compflags[MAXWLEN];	// compound flags, one for each word
    trystate_T	*sp;
    int		newscore;
    int		score;
    char_u	*byts, *fbyts, *pbyts;
    idx_T	*idxs, *fidxs, *pidxs;
    int		depth;
    int		c, c2, c3;
    int		n = 0;
    int		flags;
    garray_T	*gap;
    idx_T	arridx;
    int		len;
    char_u	*p;
    fromto_T	*ftp;
    int		fl = 0, tl;
    int		repextra = 0;	    // extra bytes in fword[] from REP item
    slang_T	*slang = lp->lp_slang;
    int		fword_ends;
    int		goodword_ends;
#ifdef DEBUG_TRIEWALK
    // Stores the name of the change made at each level.
    char_u	changename[MAXWLEN][80];
#endif
    int		breakcheckcount = 1000;
#ifdef FEAT_RELTIME
    proftime_T	time_limit;
#endif
    int		compound_ok;

    // Go through the whole case-fold tree, try changes at each node.
    // "tword[]" contains the word collected from nodes in the tree.
    // "fword[]" the word we are trying to match with (initially the bad
    // word).
    depth = 0;
    sp = &stack[0];
    CLEAR_POINTER(sp);
    sp->ts_curi = 1;

    if (soundfold)
    {
	// Going through the soundfold tree.
	byts = fbyts = slang->sl_sbyts;
	idxs = fidxs = slang->sl_sidxs;
	pbyts = NULL;
	pidxs = NULL;
	sp->ts_prefixdepth = PFD_NOPREFIX;
	sp->ts_state = STATE_START;
    }
    else
    {
	// When there are postponed prefixes we need to use these first.  At
	// the end of the prefix we continue in the case-fold tree.
	fbyts = slang->sl_fbyts;
	fidxs = slang->sl_fidxs;
	pbyts = slang->sl_pbyts;
	pidxs = slang->sl_pidxs;
	if (pbyts != NULL)
	{
	    byts = pbyts;
	    idxs = pidxs;
	    sp->ts_prefixdepth = PFD_PREFIXTREE;
	    sp->ts_state = STATE_NOPREFIX;	// try without prefix first
	}
	else
	{
	    byts = fbyts;
	    idxs = fidxs;
	    sp->ts_prefixdepth = PFD_NOPREFIX;
	    sp->ts_state = STATE_START;
	}
    }
#ifdef FEAT_RELTIME
    // The loop may take an indefinite amount of time. Break out after some
    // time.
    if (spell_suggest_timeout > 0)
	profile_setlimit(spell_suggest_timeout, &time_limit);
#endif

    // Loop to find all suggestions.  At each round we either:
    // - For the current state try one operation, advance "ts_curi",
    //   increase "depth".
    // - When a state is done go to the next, set "ts_state".
    // - When all states are tried decrease "depth".
    while (depth >= 0 && !got_int)
    {
	sp = &stack[depth];
	switch (sp->ts_state)
	{
	case STATE_START:
	case STATE_NOPREFIX:
	    // Start of node: Deal with NUL bytes, which means
	    // tword[] may end here.
	    arridx = sp->ts_arridx;	    // current node in the tree
	    len = byts[arridx];		    // bytes in this node
	    arridx += sp->ts_curi;	    // index of current byte

	    if (sp->ts_prefixdepth == PFD_PREFIXTREE)
	    {
		// Skip over the NUL bytes, we use them later.
		for (n = 0; n < len && byts[arridx + n] == 0; ++n)
		    ;
		sp->ts_curi += n;

		// Always past NUL bytes now.
		n = (int)sp->ts_state;
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_ENDNUL;
		sp->ts_save_badflags = su->su_badflags;

		// At end of a prefix or at start of prefixtree: check for
		// following word.
		if (depth < MAXWLEN - 1
			    && (byts[arridx] == 0 || n == (int)STATE_NOPREFIX))
		{
		    // Set su->su_badflags to the caps type at this position.
		    // Use the caps type until here for the prefix itself.
		    if (has_mbyte)
			n = nofold_len(fword, sp->ts_fidx, su->su_badptr);
		    else
			n = sp->ts_fidx;
		    flags = badword_captype(su->su_badptr, su->su_badptr + n);
		    su->su_badflags = badword_captype(su->su_badptr + n,
					       su->su_badptr + su->su_badlen);
#ifdef DEBUG_TRIEWALK
		    sprintf(changename[depth], "prefix");
#endif
		    go_deeper(stack, depth, 0);
		    ++depth;
		    sp = &stack[depth];
		    sp->ts_prefixdepth = depth - 1;
		    byts = fbyts;
		    idxs = fidxs;
		    sp->ts_arridx = 0;

		    // Move the prefix to preword[] with the right case
		    // and make find_keepcap_word() works.
		    tword[sp->ts_twordlen] = NUL;
		    make_case_word(tword + sp->ts_splitoff,
					  preword + sp->ts_prewordlen, flags);
		    sp->ts_prewordlen = (char_u)STRLEN(preword);
		    sp->ts_splitoff = sp->ts_twordlen;
		}
		break;
	    }

	    if (sp->ts_curi > len || byts[arridx] != 0)
	    {
		// Past bytes in node and/or past NUL bytes.
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_ENDNUL;
		sp->ts_save_badflags = su->su_badflags;
		break;
	    }

	    // End of word in tree.
	    ++sp->ts_curi;		// eat one NUL byte

	    flags = (int)idxs[arridx];

	    // Skip words with the NOSUGGEST flag.
	    if (flags & WF_NOSUGGEST)
		break;

	    fword_ends = (fword[sp->ts_fidx] == NUL
			   || (soundfold
			       ? VIM_ISWHITE(fword[sp->ts_fidx])
			       : !spell_iswordp(fword + sp->ts_fidx, curwin)));
	    tword[sp->ts_twordlen] = NUL;

	    if (sp->ts_prefixdepth <= PFD_NOTSPECIAL
					&& (sp->ts_flags & TSF_PREFIXOK) == 0
					&& pbyts != NULL)
	    {
		// There was a prefix before the word.  Check that the prefix
		// can be used with this word.
		// Count the length of the NULs in the prefix.  If there are
		// none this must be the first try without a prefix.
		n = stack[sp->ts_prefixdepth].ts_arridx;
		len = pbyts[n++];
		for (c = 0; c < len && pbyts[n + c] == 0; ++c)
		    ;
		if (c > 0)
		{
		    c = valid_word_prefix(c, n, flags,
				       tword + sp->ts_splitoff, slang, FALSE);
		    if (c == 0)
			break;

		    // Use the WF_RARE flag for a rare prefix.
		    if (c & WF_RAREPFX)
			flags |= WF_RARE;

		    // Tricky: when checking for both prefix and compounding
		    // we run into the prefix flag first.
		    // Remember that it's OK, so that we accept the prefix
		    // when arriving at a compound flag.
		    sp->ts_flags |= TSF_PREFIXOK;
		}
	    }

	    // Check NEEDCOMPOUND: can't use word without compounding.  Do try
	    // appending another compound word below.
	    if (sp->ts_complen == sp->ts_compsplit && fword_ends
						     && (flags & WF_NEEDCOMP))
		goodword_ends = FALSE;
	    else
		goodword_ends = TRUE;

	    p = NULL;
	    compound_ok = TRUE;
	    if (sp->ts_complen > sp->ts_compsplit)
	    {
		if (slang->sl_nobreak)
		{
		    // There was a word before this word.  When there was no
		    // change in this word (it was correct) add the first word
		    // as a suggestion.  If this word was corrected too, we
		    // need to check if a correct word follows.
		    if (sp->ts_fidx - sp->ts_splitfidx
					  == sp->ts_twordlen - sp->ts_splitoff
			    && STRNCMP(fword + sp->ts_splitfidx,
					tword + sp->ts_splitoff,
					 sp->ts_fidx - sp->ts_splitfidx) == 0)
		    {
			preword[sp->ts_prewordlen] = NUL;
			newscore = score_wordcount_adj(slang, sp->ts_score,
						 preword + sp->ts_prewordlen,
						 sp->ts_prewordlen > 0);
			// Add the suggestion if the score isn't too bad.
			if (newscore <= su->su_maxscore)
			    add_suggestion(su, &su->su_ga, preword,
				    sp->ts_splitfidx - repextra,
				    newscore, 0, FALSE,
				    lp->lp_sallang, FALSE);
			break;
		    }
		}
		else
		{
		    // There was a compound word before this word.  If this
		    // word does not support compounding then give up
		    // (splitting is tried for the word without compound
		    // flag).
		    if (((unsigned)flags >> 24) == 0
			    || sp->ts_twordlen - sp->ts_splitoff
						       < slang->sl_compminlen)
			break;
		    // For multi-byte chars check character length against
		    // COMPOUNDMIN.
		    if (has_mbyte
			    && slang->sl_compminlen > 0
			    && mb_charlen(tword + sp->ts_splitoff)
						       < slang->sl_compminlen)
			break;

		    compflags[sp->ts_complen] = ((unsigned)flags >> 24);
		    compflags[sp->ts_complen + 1] = NUL;
		    vim_strncpy(preword + sp->ts_prewordlen,
			    tword + sp->ts_splitoff,
			    sp->ts_twordlen - sp->ts_splitoff);

		    // Verify CHECKCOMPOUNDPATTERN  rules.
		    if (match_checkcompoundpattern(preword,  sp->ts_prewordlen,
							  &slang->sl_comppat))
			compound_ok = FALSE;

		    if (compound_ok)
		    {
			p = preword;
			while (*skiptowhite(p) != NUL)
			    p = skipwhite(skiptowhite(p));
			if (fword_ends && !can_compound(slang, p,
						compflags + sp->ts_compsplit))
			    // Compound is not allowed.  But it may still be
			    // possible if we add another (short) word.
			    compound_ok = FALSE;
		    }

		    // Get pointer to last char of previous word.
		    p = preword + sp->ts_prewordlen;
		    MB_PTR_BACK(preword, p);
		}
	    }

	    // Form the word with proper case in preword.
	    // If there is a word from a previous split, append.
	    // For the soundfold tree don't change the case, simply append.
	    if (soundfold)
		STRCPY(preword + sp->ts_prewordlen, tword + sp->ts_splitoff);
	    else if (flags & WF_KEEPCAP)
		// Must find the word in the keep-case tree.
		find_keepcap_word(slang, tword + sp->ts_splitoff,
						 preword + sp->ts_prewordlen);
	    else
	    {
		// Include badflags: If the badword is onecap or allcap
		// use that for the goodword too.  But if the badword is
		// allcap and it's only one char long use onecap.
		c = su->su_badflags;
		if ((c & WF_ALLCAP)
			&& su->su_badlen == (*mb_ptr2len)(su->su_badptr))
		    c = WF_ONECAP;
		c |= flags;

		// When appending a compound word after a word character don't
		// use Onecap.
		if (p != NULL && spell_iswordp_nmw(p, curwin))
		    c &= ~WF_ONECAP;
		make_case_word(tword + sp->ts_splitoff,
					      preword + sp->ts_prewordlen, c);
	    }

	    if (!soundfold)
	    {
		// Don't use a banned word.  It may appear again as a good
		// word, thus remember it.
		if (flags & WF_BANNED)
		{
		    add_banned(su, preword + sp->ts_prewordlen);
		    break;
		}
		if ((sp->ts_complen == sp->ts_compsplit
			    && WAS_BANNED(su, preword + sp->ts_prewordlen))
						   || WAS_BANNED(su, preword))
		{
		    if (slang->sl_compprog == NULL)
			break;
		    // the word so far was banned but we may try compounding
		    goodword_ends = FALSE;
		}
	    }

	    newscore = 0;
	    if (!soundfold)	// soundfold words don't have flags
	    {
		if ((flags & WF_REGION)
			    && (((unsigned)flags >> 16) & lp->lp_region) == 0)
		    newscore += SCORE_REGION;
		if (flags & WF_RARE)
		    newscore += SCORE_RARE;

		if (!spell_valid_case(su->su_badflags,
				  captype(preword + sp->ts_prewordlen, NULL)))
		    newscore += SCORE_ICASE;
	    }

	    // TODO: how about splitting in the soundfold tree?
	    if (fword_ends
		    && goodword_ends
		    && sp->ts_fidx >= sp->ts_fidxtry
		    && compound_ok)
	    {
		// The badword also ends: add suggestions.
#ifdef DEBUG_TRIEWALK
		if (soundfold && STRCMP(preword, "smwrd") == 0)
		{
		    int	    j;

		    // print the stack of changes that brought us here
		    smsg("------ %s -------", fword);
		    for (j = 0; j < depth; ++j)
			smsg("%s", changename[j]);
		}
#endif
		if (soundfold)
		{
		    // For soundfolded words we need to find the original
		    // words, the edit distance and then add them.
		    add_sound_suggest(su, preword, sp->ts_score, lp);
		}
		else if (sp->ts_fidx > 0)
		{
		    // Give a penalty when changing non-word char to word
		    // char, e.g., "thes," -> "these".
		    p = fword + sp->ts_fidx;
		    MB_PTR_BACK(fword, p);
		    if (!spell_iswordp(p, curwin) && *preword != NUL)
		    {
			p = preword + STRLEN(preword);
			MB_PTR_BACK(preword, p);
			if (spell_iswordp(p, curwin))
			    newscore += SCORE_NONWORD;
		    }

		    // Give a bonus to words seen before.
		    score = score_wordcount_adj(slang,
						sp->ts_score + newscore,
						preword + sp->ts_prewordlen,
						sp->ts_prewordlen > 0);

		    // Add the suggestion if the score isn't too bad.
		    if (score <= su->su_maxscore)
		    {
			add_suggestion(su, &su->su_ga, preword,
				    sp->ts_fidx - repextra,
				    score, 0, FALSE, lp->lp_sallang, FALSE);

			if (su->su_badflags & WF_MIXCAP)
			{
			    // We really don't know if the word should be
			    // upper or lower case, add both.
			    c = captype(preword, NULL);
			    if (c == 0 || c == WF_ALLCAP)
			    {
				make_case_word(tword + sp->ts_splitoff,
					      preword + sp->ts_prewordlen,
						      c == 0 ? WF_ALLCAP : 0);

				add_suggestion(su, &su->su_ga, preword,
					sp->ts_fidx - repextra,
					score + SCORE_ICASE, 0, FALSE,
					lp->lp_sallang, FALSE);
			    }
			}
		    }
		}
	    }

	    // Try word split and/or compounding.
	    if ((sp->ts_fidx >= sp->ts_fidxtry || fword_ends)
		    // Don't split halfway a character.
		    && (!has_mbyte || sp->ts_tcharlen == 0))
	    {
		int	try_compound;
		int	try_split;

		// If past the end of the bad word don't try a split.
		// Otherwise try changing the next word.  E.g., find
		// suggestions for "the the" where the second "the" is
		// different.  It's done like a split.
		// TODO: word split for soundfold words
		try_split = (sp->ts_fidx - repextra < su->su_badlen)
								&& !soundfold;

		// Get here in several situations:
		// 1. The word in the tree ends:
		//    If the word allows compounding try that.  Otherwise try
		//    a split by inserting a space.  For both check that a
		//    valid words starts at fword[sp->ts_fidx].
		//    For NOBREAK do like compounding to be able to check if
		//    the next word is valid.
		// 2. The badword does end, but it was due to a change (e.g.,
		//    a swap).  No need to split, but do check that the
		//    following word is valid.
		// 3. The badword and the word in the tree end.  It may still
		//    be possible to compound another (short) word.
		try_compound = FALSE;
		if (!soundfold
			&& !slang->sl_nocompoundsugs
			&& slang->sl_compprog != NULL
			&& ((unsigned)flags >> 24) != 0
			&& sp->ts_twordlen - sp->ts_splitoff
						       >= slang->sl_compminlen
			&& (!has_mbyte
			    || slang->sl_compminlen == 0
			    || mb_charlen(tword + sp->ts_splitoff)
						      >= slang->sl_compminlen)
			&& (slang->sl_compsylmax < MAXWLEN
			    || sp->ts_complen + 1 - sp->ts_compsplit
							  < slang->sl_compmax)
			&& (can_be_compound(sp, slang,
					 compflags, ((unsigned)flags >> 24))))

		{
		    try_compound = TRUE;
		    compflags[sp->ts_complen] = ((unsigned)flags >> 24);
		    compflags[sp->ts_complen + 1] = NUL;
		}

		// For NOBREAK we never try splitting, it won't make any word
		// valid.
		if (slang->sl_nobreak && !slang->sl_nocompoundsugs)
		    try_compound = TRUE;

		// If we could add a compound word, and it's also possible to
		// split at this point, do the split first and set
		// TSF_DIDSPLIT to avoid doing it again.
		else if (!fword_ends
			&& try_compound
			&& (sp->ts_flags & TSF_DIDSPLIT) == 0)
		{
		    try_compound = FALSE;
		    sp->ts_flags |= TSF_DIDSPLIT;
		    --sp->ts_curi;	    // do the same NUL again
		    compflags[sp->ts_complen] = NUL;
		}
		else
		    sp->ts_flags &= ~TSF_DIDSPLIT;

		if (try_split || try_compound)
		{
		    if (!try_compound && (!fword_ends || !goodword_ends))
		    {
			// If we're going to split need to check that the
			// words so far are valid for compounding.  If there
			// is only one word it must not have the NEEDCOMPOUND
			// flag.
			if (sp->ts_complen == sp->ts_compsplit
						     && (flags & WF_NEEDCOMP))
			    break;
			p = preword;
			while (*skiptowhite(p) != NUL)
			    p = skipwhite(skiptowhite(p));
			if (sp->ts_complen > sp->ts_compsplit
				&& !can_compound(slang, p,
						compflags + sp->ts_compsplit))
			    break;

			if (slang->sl_nosplitsugs)
			    newscore += SCORE_SPLIT_NO;
			else
			    newscore += SCORE_SPLIT;

			// Give a bonus to words seen before.
			newscore = score_wordcount_adj(slang, newscore,
					   preword + sp->ts_prewordlen, TRUE);
		    }

		    if (TRY_DEEPER(su, stack, depth, newscore))
		    {
			go_deeper(stack, depth, newscore);
#ifdef DEBUG_TRIEWALK
			if (!try_compound && !fword_ends)
			    sprintf(changename[depth], "%.*s-%s: split",
				 sp->ts_twordlen, tword, fword + sp->ts_fidx);
			else
			    sprintf(changename[depth], "%.*s-%s: compound",
				 sp->ts_twordlen, tword, fword + sp->ts_fidx);
#endif
			// Save things to be restored at STATE_SPLITUNDO.
			sp->ts_save_badflags = su->su_badflags;
			PROF_STORE(sp->ts_state)
			sp->ts_state = STATE_SPLITUNDO;

			++depth;
			sp = &stack[depth];

			// Append a space to preword when splitting.
			if (!try_compound && !fword_ends)
			    STRCAT(preword, " ");
			sp->ts_prewordlen = (char_u)STRLEN(preword);
			sp->ts_splitoff = sp->ts_twordlen;
			sp->ts_splitfidx = sp->ts_fidx;

			// If the badword has a non-word character at this
			// position skip it.  That means replacing the
			// non-word character with a space.  Always skip a
			// character when the word ends.  But only when the
			// good word can end.
			if (((!try_compound && !spell_iswordp_nmw(fword
							       + sp->ts_fidx,
							       curwin))
				    || fword_ends)
				&& fword[sp->ts_fidx] != NUL
				&& goodword_ends)
			{
			    int	    l;

			    l = mb_ptr2len(fword + sp->ts_fidx);
			    if (fword_ends)
			    {
				// Copy the skipped character to preword.
				mch_memmove(preword + sp->ts_prewordlen,
						      fword + sp->ts_fidx, l);
				sp->ts_prewordlen += l;
				preword[sp->ts_prewordlen] = NUL;
			    }
			    else
				sp->ts_score -= SCORE_SPLIT - SCORE_SUBST;
			    sp->ts_fidx += l;
			}

			// When compounding include compound flag in
			// compflags[] (already set above).  When splitting we
			// may start compounding over again.
			if (try_compound)
			    ++sp->ts_complen;
			else
			    sp->ts_compsplit = sp->ts_complen;
			sp->ts_prefixdepth = PFD_NOPREFIX;

			// set su->su_badflags to the caps type at this
			// position
			if (has_mbyte)
			    n = nofold_len(fword, sp->ts_fidx, su->su_badptr);
			else
			    n = sp->ts_fidx;
			su->su_badflags = badword_captype(su->su_badptr + n,
					       su->su_badptr + su->su_badlen);

			// Restart at top of the tree.
			sp->ts_arridx = 0;

			// If there are postponed prefixes, try these too.
			if (pbyts != NULL)
			{
			    byts = pbyts;
			    idxs = pidxs;
			    sp->ts_prefixdepth = PFD_PREFIXTREE;
			    PROF_STORE(sp->ts_state)
			    sp->ts_state = STATE_NOPREFIX;
			}
		    }
		}
	    }
	    break;

	case STATE_SPLITUNDO:
	    // Undo the changes done for word split or compound word.
	    su->su_badflags = sp->ts_save_badflags;

	    // Continue looking for NUL bytes.
	    PROF_STORE(sp->ts_state)
	    sp->ts_state = STATE_START;

	    // In case we went into the prefix tree.
	    byts = fbyts;
	    idxs = fidxs;
	    break;

	case STATE_ENDNUL:
	    // Past the NUL bytes in the node.
	    su->su_badflags = sp->ts_save_badflags;
	    if (fword[sp->ts_fidx] == NUL && sp->ts_tcharlen == 0)
	    {
		// The badword ends, can't use STATE_PLAIN.
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_DEL;
		break;
	    }
	    PROF_STORE(sp->ts_state)
	    sp->ts_state = STATE_PLAIN;
	    // FALLTHROUGH

	case STATE_PLAIN:
	    // Go over all possible bytes at this node, add each to tword[]
	    // and use child node.  "ts_curi" is the index.
	    arridx = sp->ts_arridx;
	    if (sp->ts_curi > byts[arridx])
	    {
		// Done all bytes at this node, do next state.  When still at
		// already changed bytes skip the other tricks.
		PROF_STORE(sp->ts_state)
		if (sp->ts_fidx >= sp->ts_fidxtry)
		    sp->ts_state = STATE_DEL;
		else
		    sp->ts_state = STATE_FINAL;
	    }
	    else
	    {
		arridx += sp->ts_curi++;
		c = byts[arridx];

		// Normal byte, go one level deeper.  If it's not equal to the
		// byte in the bad word adjust the score.  But don't even try
		// when the byte was already changed.  And don't try when we
		// just deleted this byte, accepting it is always cheaper than
		// delete + substitute.
		if (c == fword[sp->ts_fidx]
			|| (sp->ts_tcharlen > 0 && sp->ts_isdiff != DIFF_NONE))
		    newscore = 0;
		else
		    newscore = SCORE_SUBST;
		if ((newscore == 0
			    || (sp->ts_fidx >= sp->ts_fidxtry
				&& ((sp->ts_flags & TSF_DIDDEL) == 0
				    || c != fword[sp->ts_delidx])))
			&& TRY_DEEPER(su, stack, depth, newscore))
		{
		    go_deeper(stack, depth, newscore);
#ifdef DEBUG_TRIEWALK
		    if (newscore > 0)
			sprintf(changename[depth], "%.*s-%s: subst %c to %c",
				sp->ts_twordlen, tword, fword + sp->ts_fidx,
				fword[sp->ts_fidx], c);
		    else
			sprintf(changename[depth], "%.*s-%s: accept %c",
				sp->ts_twordlen, tword, fword + sp->ts_fidx,
				fword[sp->ts_fidx]);
#endif
		    ++depth;
		    sp = &stack[depth];
		    if (fword[sp->ts_fidx] != NUL)
			++sp->ts_fidx;
		    tword[sp->ts_twordlen++] = c;
		    sp->ts_arridx = idxs[arridx];
		    if (newscore == SCORE_SUBST)
			sp->ts_isdiff = DIFF_YES;
		    if (has_mbyte)
		    {
			// Multi-byte characters are a bit complicated to
			// handle: They differ when any of the bytes differ
			// and then their length may also differ.
			if (sp->ts_tcharlen == 0)
			{
			    // First byte.
			    sp->ts_tcharidx = 0;
			    sp->ts_tcharlen = MB_BYTE2LEN(c);
			    sp->ts_fcharstart = sp->ts_fidx - 1;
			    sp->ts_isdiff = (newscore != 0)
						       ? DIFF_YES : DIFF_NONE;
			}
			else if (sp->ts_isdiff == DIFF_INSERT
							    && sp->ts_fidx > 0)
			    // When inserting trail bytes don't advance in the
			    // bad word.
			    --sp->ts_fidx;
			if (++sp->ts_tcharidx == sp->ts_tcharlen)
			{
			    // Last byte of character.
			    if (sp->ts_isdiff == DIFF_YES)
			    {
				// Correct ts_fidx for the byte length of the
				// character (we didn't check that before).
				sp->ts_fidx = sp->ts_fcharstart
					    + mb_ptr2len(
						    fword + sp->ts_fcharstart);
				// For changing a composing character adjust
				// the score from SCORE_SUBST to
				// SCORE_SUBCOMP.
				if (enc_utf8
					&& utf_iscomposing(
					    utf_ptr2char(tword
						+ sp->ts_twordlen
							   - sp->ts_tcharlen))
					&& utf_iscomposing(
					    utf_ptr2char(fword
							+ sp->ts_fcharstart)))
				    sp->ts_score -=
						  SCORE_SUBST - SCORE_SUBCOMP;

				// For a similar character adjust score from
				// SCORE_SUBST to SCORE_SIMILAR.
				else if (!soundfold
					&& slang->sl_has_map
					&& similar_chars(slang,
					    mb_ptr2char(tword
						+ sp->ts_twordlen
							   - sp->ts_tcharlen),
					    mb_ptr2char(fword
							+ sp->ts_fcharstart)))
				    sp->ts_score -=
						  SCORE_SUBST - SCORE_SIMILAR;
			    }
			    else if (sp->ts_isdiff == DIFF_INSERT
					 && sp->ts_twordlen > sp->ts_tcharlen)
			    {
				p = tword + sp->ts_twordlen - sp->ts_tcharlen;
				c = mb_ptr2char(p);
				if (enc_utf8 && utf_iscomposing(c))
				{
				    // Inserting a composing char doesn't
				    // count that much.
				    sp->ts_score -= SCORE_INS - SCORE_INSCOMP;
				}
				else
				{
				    // If the previous character was the same,
				    // thus doubling a character, give a bonus
				    // to the score.  Also for the soundfold
				    // tree (might seem illogical but does
				    // give better scores).
				    MB_PTR_BACK(tword, p);
				    if (c == mb_ptr2char(p))
					sp->ts_score -= SCORE_INS
							       - SCORE_INSDUP;
				}
			    }

			    // Starting a new char, reset the length.
			    sp->ts_tcharlen = 0;
			}
		    }
		    else
		    {
			// If we found a similar char adjust the score.
			// We do this after calling go_deeper() because
			// it's slow.
			if (newscore != 0
				&& !soundfold
				&& slang->sl_has_map
				&& similar_chars(slang,
						   c, fword[sp->ts_fidx - 1]))
			    sp->ts_score -= SCORE_SUBST - SCORE_SIMILAR;
		    }
		}
	    }
	    break;

	case STATE_DEL:
	    // When past the first byte of a multi-byte char don't try
	    // delete/insert/swap a character.
	    if (has_mbyte && sp->ts_tcharlen > 0)
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_FINAL;
		break;
	    }
	    // Try skipping one character in the bad word (delete it).
	    PROF_STORE(sp->ts_state)
	    sp->ts_state = STATE_INS_PREP;
	    sp->ts_curi = 1;
	    if (soundfold && sp->ts_fidx == 0 && fword[sp->ts_fidx] == '*')
		// Deleting a vowel at the start of a word counts less, see
		// soundalike_score().
		newscore = 2 * SCORE_DEL / 3;
	    else
		newscore = SCORE_DEL;
	    if (fword[sp->ts_fidx] != NUL
				    && TRY_DEEPER(su, stack, depth, newscore))
	    {
		go_deeper(stack, depth, newscore);
#ifdef DEBUG_TRIEWALK
		sprintf(changename[depth], "%.*s-%s: delete %c",
			sp->ts_twordlen, tword, fword + sp->ts_fidx,
			fword[sp->ts_fidx]);
#endif
		++depth;

		// Remember what character we deleted, so that we can avoid
		// inserting it again.
		stack[depth].ts_flags |= TSF_DIDDEL;
		stack[depth].ts_delidx = sp->ts_fidx;

		// Advance over the character in fword[].  Give a bonus to the
		// score if the same character is following "nn" -> "n".  It's
		// a bit illogical for soundfold tree but it does give better
		// results.
		if (has_mbyte)
		{
		    c = mb_ptr2char(fword + sp->ts_fidx);
		    stack[depth].ts_fidx += mb_ptr2len(fword + sp->ts_fidx);
		    if (enc_utf8 && utf_iscomposing(c))
			stack[depth].ts_score -= SCORE_DEL - SCORE_DELCOMP;
		    else if (c == mb_ptr2char(fword + stack[depth].ts_fidx))
			stack[depth].ts_score -= SCORE_DEL - SCORE_DELDUP;
		}
		else
		{
		    ++stack[depth].ts_fidx;
		    if (fword[sp->ts_fidx] == fword[sp->ts_fidx + 1])
			stack[depth].ts_score -= SCORE_DEL - SCORE_DELDUP;
		}
		break;
	    }
	    // FALLTHROUGH

	case STATE_INS_PREP:
	    if (sp->ts_flags & TSF_DIDDEL)
	    {
		// If we just deleted a byte then inserting won't make sense,
		// a substitute is always cheaper.
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_SWAP;
		break;
	    }

	    // skip over NUL bytes
	    n = sp->ts_arridx;
	    for (;;)
	    {
		if (sp->ts_curi > byts[n])
		{
		    // Only NUL bytes at this node, go to next state.
		    PROF_STORE(sp->ts_state)
		    sp->ts_state = STATE_SWAP;
		    break;
		}
		if (byts[n + sp->ts_curi] != NUL)
		{
		    // Found a byte to insert.
		    PROF_STORE(sp->ts_state)
		    sp->ts_state = STATE_INS;
		    break;
		}
		++sp->ts_curi;
	    }
	    break;

	    // FALLTHROUGH

	case STATE_INS:
	    // Insert one byte.  Repeat this for each possible byte at this
	    // node.
	    n = sp->ts_arridx;
	    if (sp->ts_curi > byts[n])
	    {
		// Done all bytes at this node, go to next state.
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_SWAP;
		break;
	    }

	    // Do one more byte at this node, but:
	    // - Skip NUL bytes.
	    // - Skip the byte if it's equal to the byte in the word,
	    //   accepting that byte is always better.
	    n += sp->ts_curi++;

	    // break out, if we would be accessing byts buffer out of bounds
	    if (byts == slang->sl_fbyts && n >= slang->sl_fbyts_len)
	    {
		got_int = TRUE;
		break;
	    }
	    c = byts[n];
	    if (soundfold && sp->ts_twordlen == 0 && c == '*')
		// Inserting a vowel at the start of a word counts less,
		// see soundalike_score().
		newscore = 2 * SCORE_INS / 3;
	    else
		newscore = SCORE_INS;
	    if (c != fword[sp->ts_fidx]
				    && TRY_DEEPER(su, stack, depth, newscore))
	    {
		go_deeper(stack, depth, newscore);
#ifdef DEBUG_TRIEWALK
		sprintf(changename[depth], "%.*s-%s: insert %c",
			sp->ts_twordlen, tword, fword + sp->ts_fidx,
			c);
#endif
		++depth;
		sp = &stack[depth];
		tword[sp->ts_twordlen++] = c;
		sp->ts_arridx = idxs[n];
		if (has_mbyte)
		{
		    fl = MB_BYTE2LEN(c);
		    if (fl > 1)
		    {
			// There are following bytes for the same character.
			// We must find all bytes before trying
			// delete/insert/swap/etc.
			sp->ts_tcharlen = fl;
			sp->ts_tcharidx = 1;
			sp->ts_isdiff = DIFF_INSERT;
		    }
		}
		else
		    fl = 1;
		if (fl == 1)
		{
		    // If the previous character was the same, thus doubling a
		    // character, give a bonus to the score.  Also for
		    // soundfold words (illogical but does give a better
		    // score).
		    if (sp->ts_twordlen >= 2
					   && tword[sp->ts_twordlen - 2] == c)
			sp->ts_score -= SCORE_INS - SCORE_INSDUP;
		}
	    }
	    break;

	case STATE_SWAP:
	    // Swap two bytes in the bad word: "12" -> "21".
	    // We change "fword" here, it's changed back afterwards at
	    // STATE_UNSWAP.
	    p = fword + sp->ts_fidx;
	    c = *p;
	    if (c == NUL)
	    {
		// End of word, can't swap or replace.
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_FINAL;
		break;
	    }

	    // Don't swap if the first character is not a word character.
	    // SWAP3 etc. also don't make sense then.
	    if (!soundfold && !spell_iswordp(p, curwin))
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_REP_INI;
		break;
	    }

	    if (has_mbyte)
	    {
		n = MB_CPTR2LEN(p);
		c = mb_ptr2char(p);
		if (p[n] == NUL)
		    c2 = NUL;
		else if (!soundfold && !spell_iswordp(p + n, curwin))
		    c2 = c; // don't swap non-word char
		else
		    c2 = mb_ptr2char(p + n);
	    }
	    else
	    {
		if (p[1] == NUL)
		    c2 = NUL;
		else if (!soundfold && !spell_iswordp(p + 1, curwin))
		    c2 = c; // don't swap non-word char
		else
		    c2 = p[1];
	    }

	    // When the second character is NUL we can't swap.
	    if (c2 == NUL)
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_REP_INI;
		break;
	    }

	    // When characters are identical, swap won't do anything.
	    // Also get here if the second char is not a word character.
	    if (c == c2)
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_SWAP3;
		break;
	    }
	    if (c2 != NUL && TRY_DEEPER(su, stack, depth, SCORE_SWAP))
	    {
		go_deeper(stack, depth, SCORE_SWAP);
#ifdef DEBUG_TRIEWALK
		sprintf(changename[depth], "%.*s-%s: swap %c and %c",
			sp->ts_twordlen, tword, fword + sp->ts_fidx,
			c, c2);
#endif
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_UNSWAP;
		++depth;
		if (has_mbyte)
		{
		    fl = mb_char2len(c2);
		    mch_memmove(p, p + n, fl);
		    mb_char2bytes(c, p + fl);
		    stack[depth].ts_fidxtry = sp->ts_fidx + n + fl;
		}
		else
		{
		    p[0] = c2;
		    p[1] = c;
		    stack[depth].ts_fidxtry = sp->ts_fidx + 2;
		}
	    }
	    else
	    {
		// If this swap doesn't work then SWAP3 won't either.
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_REP_INI;
	    }
	    break;

	case STATE_UNSWAP:
	    // Undo the STATE_SWAP swap: "21" -> "12".
	    p = fword + sp->ts_fidx;
	    if (has_mbyte)
	    {
		n = mb_ptr2len(p);
		c = mb_ptr2char(p + n);
		mch_memmove(p + mb_ptr2len(p + n), p, n);
		mb_char2bytes(c, p);
	    }
	    else
	    {
		c = *p;
		*p = p[1];
		p[1] = c;
	    }
	    // FALLTHROUGH

	case STATE_SWAP3:
	    // Swap two bytes, skipping one: "123" -> "321".  We change
	    // "fword" here, it's changed back afterwards at STATE_UNSWAP3.
	    p = fword + sp->ts_fidx;
	    if (has_mbyte)
	    {
		n = MB_CPTR2LEN(p);
		c = mb_ptr2char(p);
		fl = MB_CPTR2LEN(p + n);
		c2 = mb_ptr2char(p + n);
		if (!soundfold && !spell_iswordp(p + n + fl, curwin))
		    c3 = c;	// don't swap non-word char
		else
		    c3 = mb_ptr2char(p + n + fl);
	    }
	    else
	    {
		c = *p;
		c2 = p[1];
		if (!soundfold && !spell_iswordp(p + 2, curwin))
		    c3 = c;	// don't swap non-word char
		else
		    c3 = p[2];
	    }

	    // When characters are identical: "121" then SWAP3 result is
	    // identical, ROT3L result is same as SWAP: "211", ROT3L result is
	    // same as SWAP on next char: "112".  Thus skip all swapping.
	    // Also skip when c3 is NUL.
	    // Also get here when the third character is not a word character.
	    // Second character may any char: "a.b" -> "b.a"
	    if (c == c3 || c3 == NUL)
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_REP_INI;
		break;
	    }
	    if (TRY_DEEPER(su, stack, depth, SCORE_SWAP3))
	    {
		go_deeper(stack, depth, SCORE_SWAP3);
#ifdef DEBUG_TRIEWALK
		sprintf(changename[depth], "%.*s-%s: swap3 %c and %c",
			sp->ts_twordlen, tword, fword + sp->ts_fidx,
			c, c3);
#endif
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_UNSWAP3;
		++depth;
		if (has_mbyte)
		{
		    tl = mb_char2len(c3);
		    mch_memmove(p, p + n + fl, tl);
		    mb_char2bytes(c2, p + tl);
		    mb_char2bytes(c, p + fl + tl);
		    stack[depth].ts_fidxtry = sp->ts_fidx + n + fl + tl;
		}
		else
		{
		    p[0] = p[2];
		    p[2] = c;
		    stack[depth].ts_fidxtry = sp->ts_fidx + 3;
		}
	    }
	    else
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_REP_INI;
	    }
	    break;

	case STATE_UNSWAP3:
	    // Undo STATE_SWAP3: "321" -> "123"
	    p = fword + sp->ts_fidx;
	    if (has_mbyte)
	    {
		n = mb_ptr2len(p);
		c2 = mb_ptr2char(p + n);
		fl = mb_ptr2len(p + n);
		c = mb_ptr2char(p + n + fl);
		tl = mb_ptr2len(p + n + fl);
		mch_memmove(p + fl + tl, p, n);
		mb_char2bytes(c, p);
		mb_char2bytes(c2, p + tl);
		p = p + tl;
	    }
	    else
	    {
		c = *p;
		*p = p[2];
		p[2] = c;
		++p;
	    }

	    if (!soundfold && !spell_iswordp(p, curwin))
	    {
		// Middle char is not a word char, skip the rotate.  First and
		// third char were already checked at swap and swap3.
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_REP_INI;
		break;
	    }

	    // Rotate three characters left: "123" -> "231".  We change
	    // "fword" here, it's changed back afterwards at STATE_UNROT3L.
	    if (TRY_DEEPER(su, stack, depth, SCORE_SWAP3))
	    {
		go_deeper(stack, depth, SCORE_SWAP3);
#ifdef DEBUG_TRIEWALK
		p = fword + sp->ts_fidx;
		sprintf(changename[depth], "%.*s-%s: rotate left %c%c%c",
			sp->ts_twordlen, tword, fword + sp->ts_fidx,
			p[0], p[1], p[2]);
#endif
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_UNROT3L;
		++depth;
		p = fword + sp->ts_fidx;
		if (has_mbyte)
		{
		    n = MB_CPTR2LEN(p);
		    c = mb_ptr2char(p);
		    fl = MB_CPTR2LEN(p + n);
		    fl += MB_CPTR2LEN(p + n + fl);
		    mch_memmove(p, p + n, fl);
		    mb_char2bytes(c, p + fl);
		    stack[depth].ts_fidxtry = sp->ts_fidx + n + fl;
		}
		else
		{
		    c = *p;
		    *p = p[1];
		    p[1] = p[2];
		    p[2] = c;
		    stack[depth].ts_fidxtry = sp->ts_fidx + 3;
		}
	    }
	    else
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_REP_INI;
	    }
	    break;

	case STATE_UNROT3L:
	    // Undo ROT3L: "231" -> "123"
	    p = fword + sp->ts_fidx;
	    if (has_mbyte)
	    {
		n = mb_ptr2len(p);
		n += mb_ptr2len(p + n);
		c = mb_ptr2char(p + n);
		tl = mb_ptr2len(p + n);
		mch_memmove(p + tl, p, n);
		mb_char2bytes(c, p);
	    }
	    else
	    {
		c = p[2];
		p[2] = p[1];
		p[1] = *p;
		*p = c;
	    }

	    // Rotate three bytes right: "123" -> "312".  We change "fword"
	    // here, it's changed back afterwards at STATE_UNROT3R.
	    if (TRY_DEEPER(su, stack, depth, SCORE_SWAP3))
	    {
		go_deeper(stack, depth, SCORE_SWAP3);
#ifdef DEBUG_TRIEWALK
		p = fword + sp->ts_fidx;
		sprintf(changename[depth], "%.*s-%s: rotate right %c%c%c",
			sp->ts_twordlen, tword, fword + sp->ts_fidx,
			p[0], p[1], p[2]);
#endif
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_UNROT3R;
		++depth;
		p = fword + sp->ts_fidx;
		if (has_mbyte)
		{
		    n = MB_CPTR2LEN(p);
		    n += MB_CPTR2LEN(p + n);
		    c = mb_ptr2char(p + n);
		    tl = MB_CPTR2LEN(p + n);
		    mch_memmove(p + tl, p, n);
		    mb_char2bytes(c, p);
		    stack[depth].ts_fidxtry = sp->ts_fidx + n + tl;
		}
		else
		{
		    c = p[2];
		    p[2] = p[1];
		    p[1] = *p;
		    *p = c;
		    stack[depth].ts_fidxtry = sp->ts_fidx + 3;
		}
	    }
	    else
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_REP_INI;
	    }
	    break;

	case STATE_UNROT3R:
	    // Undo ROT3R: "312" -> "123"
	    p = fword + sp->ts_fidx;
	    if (has_mbyte)
	    {
		c = mb_ptr2char(p);
		tl = mb_ptr2len(p);
		n = mb_ptr2len(p + tl);
		n += mb_ptr2len(p + tl + n);
		mch_memmove(p, p + tl, n);
		mb_char2bytes(c, p + n);
	    }
	    else
	    {
		c = *p;
		*p = p[1];
		p[1] = p[2];
		p[2] = c;
	    }
	    // FALLTHROUGH

	case STATE_REP_INI:
	    // Check if matching with REP items from the .aff file would work.
	    // Quickly skip if:
	    // - there are no REP items and we are not in the soundfold trie
	    // - the score is going to be too high anyway
	    // - already applied a REP item or swapped here
	    if ((lp->lp_replang == NULL && !soundfold)
		    || sp->ts_score + SCORE_REP >= su->su_maxscore
		    || sp->ts_fidx < sp->ts_fidxtry)
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_FINAL;
		break;
	    }

	    // Use the first byte to quickly find the first entry that may
	    // match.  If the index is -1 there is none.
	    if (soundfold)
		sp->ts_curi = slang->sl_repsal_first[fword[sp->ts_fidx]];
	    else
		sp->ts_curi = lp->lp_replang->sl_rep_first[fword[sp->ts_fidx]];

	    if (sp->ts_curi < 0)
	    {
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_FINAL;
		break;
	    }

	    PROF_STORE(sp->ts_state)
	    sp->ts_state = STATE_REP;
	    // FALLTHROUGH

	case STATE_REP:
	    // Try matching with REP items from the .aff file.  For each match
	    // replace the characters and check if the resulting word is
	    // valid.
	    p = fword + sp->ts_fidx;

	    if (soundfold)
		gap = &slang->sl_repsal;
	    else
		gap = &lp->lp_replang->sl_rep;
	    while (sp->ts_curi < gap->ga_len)
	    {
		ftp = (fromto_T *)gap->ga_data + sp->ts_curi++;
		if (*ftp->ft_from != *p)
		{
		    // past possible matching entries
		    sp->ts_curi = gap->ga_len;
		    break;
		}
		if (STRNCMP(ftp->ft_from, p, STRLEN(ftp->ft_from)) == 0
			&& TRY_DEEPER(su, stack, depth, SCORE_REP))
		{
		    go_deeper(stack, depth, SCORE_REP);
#ifdef DEBUG_TRIEWALK
		    sprintf(changename[depth], "%.*s-%s: replace %s with %s",
			    sp->ts_twordlen, tword, fword + sp->ts_fidx,
			    ftp->ft_from, ftp->ft_to);
#endif
		    // Need to undo this afterwards.
		    PROF_STORE(sp->ts_state)
		    sp->ts_state = STATE_REP_UNDO;

		    // Change the "from" to the "to" string.
		    ++depth;
		    fl = (int)STRLEN(ftp->ft_from);
		    tl = (int)STRLEN(ftp->ft_to);
		    if (fl != tl)
		    {
			STRMOVE(p + tl, p + fl);
			repextra += tl - fl;
		    }
		    mch_memmove(p, ftp->ft_to, tl);
		    stack[depth].ts_fidxtry = sp->ts_fidx + tl;
		    stack[depth].ts_tcharlen = 0;
		    break;
		}
	    }

	    if (sp->ts_curi >= gap->ga_len && sp->ts_state == STATE_REP)
	    {
		// No (more) matches.
		PROF_STORE(sp->ts_state)
		sp->ts_state = STATE_FINAL;
	    }

	    break;

	case STATE_REP_UNDO:
	    // Undo a REP replacement and continue with the next one.
	    if (soundfold)
		gap = &slang->sl_repsal;
	    else
		gap = &lp->lp_replang->sl_rep;
	    ftp = (fromto_T *)gap->ga_data + sp->ts_curi - 1;
	    fl = (int)STRLEN(ftp->ft_from);
	    tl = (int)STRLEN(ftp->ft_to);
	    p = fword + sp->ts_fidx;
	    if (fl != tl)
	    {
		STRMOVE(p + fl, p + tl);
		repextra -= tl - fl;
	    }
	    mch_memmove(p, ftp->ft_from, fl);
	    PROF_STORE(sp->ts_state)
	    sp->ts_state = STATE_REP;
	    break;

	default:
	    // Did all possible states at this level, go up one level.
	    --depth;

	    if (depth >= 0 && stack[depth].ts_prefixdepth == PFD_PREFIXTREE)
	    {
		// Continue in or go back to the prefix tree.
		byts = pbyts;
		idxs = pidxs;
	    }

	    // Don't check for CTRL-C too often, it takes time.
	    if (--breakcheckcount == 0)
	    {
		ui_breakcheck();
		breakcheckcount = 1000;
#ifdef FEAT_RELTIME
		if (spell_suggest_timeout > 0
					  && profile_passed_limit(&time_limit))
		    got_int = TRUE;
#endif
	    }
	}
    }
}


/*
 * Go one level deeper in the tree.
 */
    static void
go_deeper(trystate_T *stack, int depth, int score_add)
{
    stack[depth + 1] = stack[depth];
    stack[depth + 1].ts_state = STATE_START;
    stack[depth + 1].ts_score = stack[depth].ts_score + score_add;
    stack[depth + 1].ts_curi = 1;	// start just after length byte
    stack[depth + 1].ts_flags = 0;
}

/*
 * "fword" is a good word with case folded.  Find the matching keep-case
 * words and put it in "kword".
 * Theoretically there could be several keep-case words that result in the
 * same case-folded word, but we only find one...
 */
    static void
find_keepcap_word(slang_T *slang, char_u *fword, char_u *kword)
{
    char_u	uword[MAXWLEN];		// "fword" in upper-case
    int		depth;
    idx_T	tryidx;

    // The following arrays are used at each depth in the tree.
    idx_T	arridx[MAXWLEN];
    int		round[MAXWLEN];
    int		fwordidx[MAXWLEN];
    int		uwordidx[MAXWLEN];
    int		kwordlen[MAXWLEN];

    int		flen, ulen;
    int		l;
    int		len;
    int		c;
    idx_T	lo, hi, m;
    char_u	*p;
    char_u	*byts = slang->sl_kbyts;    // array with bytes of the words
    idx_T	*idxs = slang->sl_kidxs;    // array with indexes

    if (byts == NULL)
    {
	// array is empty: "cannot happen"
	*kword = NUL;
	return;
    }

    // Make an all-cap version of "fword".
    allcap_copy(fword, uword);

    // Each character needs to be tried both case-folded and upper-case.
    // All this gets very complicated if we keep in mind that changing case
    // may change the byte length of a multi-byte character...
    depth = 0;
    arridx[0] = 0;
    round[0] = 0;
    fwordidx[0] = 0;
    uwordidx[0] = 0;
    kwordlen[0] = 0;
    while (depth >= 0)
    {
	if (fword[fwordidx[depth]] == NUL)
	{
	    // We are at the end of "fword".  If the tree allows a word to end
	    // here we have found a match.
	    if (byts[arridx[depth] + 1] == 0)
	    {
		kword[kwordlen[depth]] = NUL;
		return;
	    }

	    // kword is getting too long, continue one level up
	    --depth;
	}
	else if (++round[depth] > 2)
	{
	    // tried both fold-case and upper-case character, continue one
	    // level up
	    --depth;
	}
	else
	{
	    // round[depth] == 1: Try using the folded-case character.
	    // round[depth] == 2: Try using the upper-case character.
	    if (has_mbyte)
	    {
		flen = MB_CPTR2LEN(fword + fwordidx[depth]);
		ulen = MB_CPTR2LEN(uword + uwordidx[depth]);
	    }
	    else
		ulen = flen = 1;
	    if (round[depth] == 1)
	    {
		p = fword + fwordidx[depth];
		l = flen;
	    }
	    else
	    {
		p = uword + uwordidx[depth];
		l = ulen;
	    }

	    for (tryidx = arridx[depth]; l > 0; --l)
	    {
		// Perform a binary search in the list of accepted bytes.
		len = byts[tryidx++];
		c = *p++;
		lo = tryidx;
		hi = tryidx + len - 1;
		while (lo < hi)
		{
		    m = (lo + hi) / 2;
		    if (byts[m] > c)
			hi = m - 1;
		    else if (byts[m] < c)
			lo = m + 1;
		    else
		    {
			lo = hi = m;
			break;
		    }
		}

		// Stop if there is no matching byte.
		if (hi < lo || byts[lo] != c)
		    break;

		// Continue at the child (if there is one).
		tryidx = idxs[lo];
	    }

	    if (l == 0)
	    {
		// Found the matching char.  Copy it to "kword" and go a
		// level deeper.
		if (round[depth] == 1)
		{
		    STRNCPY(kword + kwordlen[depth], fword + fwordidx[depth],
									flen);
		    kwordlen[depth + 1] = kwordlen[depth] + flen;
		}
		else
		{
		    STRNCPY(kword + kwordlen[depth], uword + uwordidx[depth],
									ulen);
		    kwordlen[depth + 1] = kwordlen[depth] + ulen;
		}
		fwordidx[depth + 1] = fwordidx[depth] + flen;
		uwordidx[depth + 1] = uwordidx[depth] + ulen;

		++depth;
		arridx[depth] = tryidx;
		round[depth] = 0;
	    }
	}
    }

    // Didn't find it: "cannot happen".
    *kword = NUL;
}

/*
 * Compute the sound-a-like score for suggestions in su->su_ga and add them to
 * su->su_sga.
 */
    static void
score_comp_sal(suginfo_T *su)
{
    langp_T	*lp;
    char_u	badsound[MAXWLEN];
    int		i;
    suggest_T   *stp;
    suggest_T   *sstp;
    int		score;
    int		lpi;

    if (ga_grow(&su->su_sga, su->su_ga.ga_len) == FAIL)
	return;

    // Use the sound-folding of the first language that supports it.
    for (lpi = 0; lpi < curwin->w_s->b_langp.ga_len; ++lpi)
    {
	lp = LANGP_ENTRY(curwin->w_s->b_langp, lpi);
	if (lp->lp_slang->sl_sal.ga_len > 0)
	{
	    // soundfold the bad word
	    spell_soundfold(lp->lp_slang, su->su_fbadword, TRUE, badsound);

	    for (i = 0; i < su->su_ga.ga_len; ++i)
	    {
		stp = &SUG(su->su_ga, i);

		// Case-fold the suggested word, sound-fold it and compute the
		// sound-a-like score.
		score = stp_sal_score(stp, su, lp->lp_slang, badsound);
		if (score < SCORE_MAXMAX)
		{
		    // Add the suggestion.
		    sstp = &SUG(su->su_sga, su->su_sga.ga_len);
		    sstp->st_word = vim_strsave(stp->st_word);
		    if (sstp->st_word != NULL)
		    {
			sstp->st_wordlen = stp->st_wordlen;
			sstp->st_score = score;
			sstp->st_altscore = 0;
			sstp->st_orglen = stp->st_orglen;
			++su->su_sga.ga_len;
		    }
		}
	    }
	    break;
	}
    }
}

/*
 * Combine the list of suggestions in su->su_ga and su->su_sga.
 * They are entwined.
 */
    static void
score_combine(suginfo_T *su)
{
    int		i;
    int		j;
    garray_T	ga;
    garray_T	*gap;
    langp_T	*lp;
    suggest_T	*stp;
    char_u	*p;
    char_u	badsound[MAXWLEN];
    int		round;
    int		lpi;
    slang_T	*slang = NULL;

    // Add the alternate score to su_ga.
    for (lpi = 0; lpi < curwin->w_s->b_langp.ga_len; ++lpi)
    {
	lp = LANGP_ENTRY(curwin->w_s->b_langp, lpi);
	if (lp->lp_slang->sl_sal.ga_len > 0)
	{
	    // soundfold the bad word
	    slang = lp->lp_slang;
	    spell_soundfold(slang, su->su_fbadword, TRUE, badsound);

	    for (i = 0; i < su->su_ga.ga_len; ++i)
	    {
		stp = &SUG(su->su_ga, i);
		stp->st_altscore = stp_sal_score(stp, su, slang, badsound);
		if (stp->st_altscore == SCORE_MAXMAX)
		    stp->st_score = (stp->st_score * 3 + SCORE_BIG) / 4;
		else
		    stp->st_score = (stp->st_score * 3
						  + stp->st_altscore) / 4;
		stp->st_salscore = FALSE;
	    }
	    break;
	}
    }

    if (slang == NULL)	// Using "double" without sound folding.
    {
	(void)cleanup_suggestions(&su->su_ga, su->su_maxscore,
							     su->su_maxcount);
	return;
    }

    // Add the alternate score to su_sga.
    for (i = 0; i < su->su_sga.ga_len; ++i)
    {
	stp = &SUG(su->su_sga, i);
	stp->st_altscore = spell_edit_score(slang,
						su->su_badword, stp->st_word);
	if (stp->st_score == SCORE_MAXMAX)
	    stp->st_score = (SCORE_BIG * 7 + stp->st_altscore) / 8;
	else
	    stp->st_score = (stp->st_score * 7 + stp->st_altscore) / 8;
	stp->st_salscore = TRUE;
    }

    // Remove bad suggestions, sort the suggestions and truncate at "maxcount"
    // for both lists.
    check_suggestions(su, &su->su_ga);
    (void)cleanup_suggestions(&su->su_ga, su->su_maxscore, su->su_maxcount);
    check_suggestions(su, &su->su_sga);
    (void)cleanup_suggestions(&su->su_sga, su->su_maxscore, su->su_maxcount);

    ga_init2(&ga, sizeof(suginfo_T), 1);
    if (ga_grow(&ga, su->su_ga.ga_len + su->su_sga.ga_len) == FAIL)
	return;

    stp = &SUG(ga, 0);
    for (i = 0; i < su->su_ga.ga_len || i < su->su_sga.ga_len; ++i)
    {
	// round 1: get a suggestion from su_ga
	// round 2: get a suggestion from su_sga
	for (round = 1; round <= 2; ++round)
	{
	    gap = round == 1 ? &su->su_ga : &su->su_sga;
	    if (i < gap->ga_len)
	    {
		// Don't add a word if it's already there.
		p = SUG(*gap, i).st_word;
		for (j = 0; j < ga.ga_len; ++j)
		    if (STRCMP(stp[j].st_word, p) == 0)
			break;
		if (j == ga.ga_len)
		    stp[ga.ga_len++] = SUG(*gap, i);
		else
		    vim_free(p);
	    }
	}
    }

    ga_clear(&su->su_ga);
    ga_clear(&su->su_sga);

    // Truncate the list to the number of suggestions that will be displayed.
    if (ga.ga_len > su->su_maxcount)
    {
	for (i = su->su_maxcount; i < ga.ga_len; ++i)
	    vim_free(stp[i].st_word);
	ga.ga_len = su->su_maxcount;
    }

    su->su_ga = ga;
}

/*
 * For the goodword in "stp" compute the soundalike score compared to the
 * badword.
 */
    static int
stp_sal_score(
    suggest_T	*stp,
    suginfo_T	*su,
    slang_T	*slang,
    char_u	*badsound)	// sound-folded badword
{
    char_u	*p;
    char_u	*pbad;
    char_u	*pgood;
    char_u	badsound2[MAXWLEN];
    char_u	fword[MAXWLEN];
    char_u	goodsound[MAXWLEN];
    char_u	goodword[MAXWLEN];
    int		lendiff;

    lendiff = (int)(su->su_badlen - stp->st_orglen);
    if (lendiff >= 0)
	pbad = badsound;
    else
    {
	// soundfold the bad word with more characters following
	(void)spell_casefold(curwin,
				su->su_badptr, stp->st_orglen, fword, MAXWLEN);

	// When joining two words the sound often changes a lot.  E.g., "t he"
	// sounds like "t h" while "the" sounds like "@".  Avoid that by
	// removing the space.  Don't do it when the good word also contains a
	// space.
	if (VIM_ISWHITE(su->su_badptr[su->su_badlen])
					 && *skiptowhite(stp->st_word) == NUL)
	    for (p = fword; *(p = skiptowhite(p)) != NUL; )
		STRMOVE(p, p + 1);

	spell_soundfold(slang, fword, TRUE, badsound2);
	pbad = badsound2;
    }

    if (lendiff > 0 && stp->st_wordlen + lendiff < MAXWLEN)
    {
	// Add part of the bad word to the good word, so that we soundfold
	// what replaces the bad word.
	STRCPY(goodword, stp->st_word);
	vim_strncpy(goodword + stp->st_wordlen,
			    su->su_badptr + su->su_badlen - lendiff, lendiff);
	pgood = goodword;
    }
    else
	pgood = stp->st_word;

    // Sound-fold the word and compute the score for the difference.
    spell_soundfold(slang, pgood, FALSE, goodsound);

    return soundalike_score(goodsound, pbad);
}

// structure used to store soundfolded words that add_sound_suggest() has
// handled already.
typedef struct
{
    short	sft_score;	// lowest score used
    char_u	sft_word[1];    // soundfolded word, actually longer
} sftword_T;

static sftword_T dumsft;
#define HIKEY2SFT(p)  ((sftword_T *)((p) - (dumsft.sft_word - (char_u *)&dumsft)))
#define HI2SFT(hi)     HIKEY2SFT((hi)->hi_key)

/*
 * Prepare for calling suggest_try_soundalike().
 */
    static void
suggest_try_soundalike_prep(void)
{
    langp_T	*lp;
    int		lpi;
    slang_T	*slang;

    // Do this for all languages that support sound folding and for which a
    // .sug file has been loaded.
    for (lpi = 0; lpi < curwin->w_s->b_langp.ga_len; ++lpi)
    {
	lp = LANGP_ENTRY(curwin->w_s->b_langp, lpi);
	slang = lp->lp_slang;
	if (slang->sl_sal.ga_len > 0 && slang->sl_sbyts != NULL)
	    // prepare the hashtable used by add_sound_suggest()
	    hash_init(&slang->sl_sounddone);
    }
}

/*
 * Find suggestions by comparing the word in a sound-a-like form.
 * Note: This doesn't support postponed prefixes.
 */
    static void
suggest_try_soundalike(suginfo_T *su)
{
    char_u	salword[MAXWLEN];
    langp_T	*lp;
    int		lpi;
    slang_T	*slang;

    // Do this for all languages that support sound folding and for which a
    // .sug file has been loaded.
    for (lpi = 0; lpi < curwin->w_s->b_langp.ga_len; ++lpi)
    {
	lp = LANGP_ENTRY(curwin->w_s->b_langp, lpi);
	slang = lp->lp_slang;
	if (slang->sl_sal.ga_len > 0 && slang->sl_sbyts != NULL)
	{
	    // soundfold the bad word
	    spell_soundfold(slang, su->su_fbadword, TRUE, salword);

	    // try all kinds of inserts/deletes/swaps/etc.
	    // TODO: also soundfold the next words, so that we can try joining
	    // and splitting
#ifdef SUGGEST_PROFILE
	    prof_init();
#endif
	    suggest_trie_walk(su, lp, salword, TRUE);
#ifdef SUGGEST_PROFILE
	    prof_report("soundalike");
#endif
	}
    }
}

/*
 * Finish up after calling suggest_try_soundalike().
 */
    static void
suggest_try_soundalike_finish(void)
{
    langp_T	*lp;
    int		lpi;
    slang_T	*slang;
    int		todo;
    hashitem_T	*hi;

    // Do this for all languages that support sound folding and for which a
    // .sug file has been loaded.
    for (lpi = 0; lpi < curwin->w_s->b_langp.ga_len; ++lpi)
    {
	lp = LANGP_ENTRY(curwin->w_s->b_langp, lpi);
	slang = lp->lp_slang;
	if (slang->sl_sal.ga_len > 0 && slang->sl_sbyts != NULL)
	{
	    // Free the info about handled words.
	    todo = (int)slang->sl_sounddone.ht_used;
	    FOR_ALL_HASHTAB_ITEMS(&slang->sl_sounddone, hi, todo)
		if (!HASHITEM_EMPTY(hi))
		{
		    vim_free(HI2SFT(hi));
		    --todo;
		}

	    // Clear the hashtable, it may also be used by another region.
	    hash_clear(&slang->sl_sounddone);
	    hash_init(&slang->sl_sounddone);
	}
    }
}

/*
 * A match with a soundfolded word is found.  Add the good word(s) that
 * produce this soundfolded word.
 */
    static void
add_sound_suggest(
    suginfo_T	*su,
    char_u	*goodword,
    int		score,		// soundfold score
    langp_T	*lp)
{
    slang_T	*slang = lp->lp_slang;	// language for sound folding
    int		sfwordnr;
    char_u	*nrline;
    int		orgnr;
    char_u	theword[MAXWLEN];
    int		i;
    int		wlen;
    char_u	*byts;
    idx_T	*idxs;
    int		n;
    int		wordcount;
    int		wc;
    int		goodscore;
    hash_T	hash;
    hashitem_T  *hi;
    sftword_T	*sft;
    int		bc, gc;
    int		limit;

    // It's very well possible that the same soundfold word is found several
    // times with different scores.  Since the following is quite slow only do
    // the words that have a better score than before.  Use a hashtable to
    // remember the words that have been done.
    hash = hash_hash(goodword);
    hi = hash_lookup(&slang->sl_sounddone, goodword, hash);
    if (HASHITEM_EMPTY(hi))
    {
	sft = alloc(offsetof(sftword_T, sft_word) + STRLEN(goodword) + 1);
	if (sft != NULL)
	{
	    sft->sft_score = score;
	    STRCPY(sft->sft_word, goodword);
	    hash_add_item(&slang->sl_sounddone, hi, sft->sft_word, hash);
	}
    }
    else
    {
	sft = HI2SFT(hi);
	if (score >= sft->sft_score)
	    return;
	sft->sft_score = score;
    }

    // Find the word nr in the soundfold tree.
    sfwordnr = soundfold_find(slang, goodword);
    if (sfwordnr < 0)
    {
	internal_error("add_sound_suggest()");
	return;
    }

    // go over the list of good words that produce this soundfold word
    nrline = ml_get_buf(slang->sl_sugbuf, (linenr_T)(sfwordnr + 1), FALSE);
    orgnr = 0;
    while (*nrline != NUL)
    {
	// The wordnr was stored in a minimal nr of bytes as an offset to the
	// previous wordnr.
	orgnr += bytes2offset(&nrline);

	byts = slang->sl_fbyts;
	idxs = slang->sl_fidxs;

	// Lookup the word "orgnr" one of the two tries.
	n = 0;
	wordcount = 0;
	for (wlen = 0; wlen < MAXWLEN - 3; ++wlen)
	{
	    i = 1;
	    if (wordcount == orgnr && byts[n + 1] == NUL)
		break;	// found end of word

	    if (byts[n + 1] == NUL)
		++wordcount;

	    // skip over the NUL bytes
	    for ( ; byts[n + i] == NUL; ++i)
		if (i > byts[n])	// safety check
		{
		    STRCPY(theword + wlen, "BAD");
		    wlen += 3;
		    goto badword;
		}

	    // One of the siblings must have the word.
	    for ( ; i < byts[n]; ++i)
	    {
		wc = idxs[idxs[n + i]];	// nr of words under this byte
		if (wordcount + wc > orgnr)
		    break;
		wordcount += wc;
	    }

	    theword[wlen] = byts[n + i];
	    n = idxs[n + i];
	}
badword:
	theword[wlen] = NUL;

	// Go over the possible flags and regions.
	for (; i <= byts[n] && byts[n + i] == NUL; ++i)
	{
	    char_u	cword[MAXWLEN];
	    char_u	*p;
	    int		flags = (int)idxs[n + i];

	    // Skip words with the NOSUGGEST flag
	    if (flags & WF_NOSUGGEST)
		continue;

	    if (flags & WF_KEEPCAP)
	    {
		// Must find the word in the keep-case tree.
		find_keepcap_word(slang, theword, cword);
		p = cword;
	    }
	    else
	    {
		flags |= su->su_badflags;
		if ((flags & WF_CAPMASK) != 0)
		{
		    // Need to fix case according to "flags".
		    make_case_word(theword, cword, flags);
		    p = cword;
		}
		else
		    p = theword;
	    }

	    // Add the suggestion.
	    if (sps_flags & SPS_DOUBLE)
	    {
		// Add the suggestion if the score isn't too bad.
		if (score <= su->su_maxscore)
		    add_suggestion(su, &su->su_sga, p, su->su_badlen,
					       score, 0, FALSE, slang, FALSE);
	    }
	    else
	    {
		// Add a penalty for words in another region.
		if ((flags & WF_REGION)
			    && (((unsigned)flags >> 16) & lp->lp_region) == 0)
		    goodscore = SCORE_REGION;
		else
		    goodscore = 0;

		// Add a small penalty for changing the first letter from
		// lower to upper case.  Helps for "tath" -> "Kath", which is
		// less common than "tath" -> "path".  Don't do it when the
		// letter is the same, that has already been counted.
		gc = PTR2CHAR(p);
		if (SPELL_ISUPPER(gc))
		{
		    bc = PTR2CHAR(su->su_badword);
		    if (!SPELL_ISUPPER(bc)
				      && SPELL_TOFOLD(bc) != SPELL_TOFOLD(gc))
			goodscore += SCORE_ICASE / 2;
		}

		// Compute the score for the good word.  This only does letter
		// insert/delete/swap/replace.  REP items are not considered,
		// which may make the score a bit higher.
		// Use a limit for the score to make it work faster.  Use
		// MAXSCORE(), because RESCORE() will change the score.
		// If the limit is very high then the iterative method is
		// inefficient, using an array is quicker.
		limit = MAXSCORE(su->su_sfmaxscore - goodscore, score);
		if (limit > SCORE_LIMITMAX)
		    goodscore += spell_edit_score(slang, su->su_badword, p);
		else
		    goodscore += spell_edit_score_limit(slang, su->su_badword,
								    p, limit);

		// When going over the limit don't bother to do the rest.
		if (goodscore < SCORE_MAXMAX)
		{
		    // Give a bonus to words seen before.
		    goodscore = score_wordcount_adj(slang, goodscore, p, FALSE);

		    // Add the suggestion if the score isn't too bad.
		    goodscore = RESCORE(goodscore, score);
		    if (goodscore <= su->su_sfmaxscore)
			add_suggestion(su, &su->su_ga, p, su->su_badlen,
					 goodscore, score, TRUE, slang, TRUE);
		}
	    }
	}
	// smsg("word %s (%d): %s (%d)", sftword, sftnr, theword, orgnr);
    }
}

/*
 * Find word "word" in fold-case tree for "slang" and return the word number.
 */
    static int
soundfold_find(slang_T *slang, char_u *word)
{
    idx_T	arridx = 0;
    int		len;
    int		wlen = 0;
    int		c;
    char_u	*ptr = word;
    char_u	*byts;
    idx_T	*idxs;
    int		wordnr = 0;

    byts = slang->sl_sbyts;
    idxs = slang->sl_sidxs;

    for (;;)
    {
	// First byte is the number of possible bytes.
	len = byts[arridx++];

	// If the first possible byte is a zero the word could end here.
	// If the word ends we found the word.  If not skip the NUL bytes.
	c = ptr[wlen];
	if (byts[arridx] == NUL)
	{
	    if (c == NUL)
		break;

	    // Skip over the zeros, there can be several.
	    while (len > 0 && byts[arridx] == NUL)
	    {
		++arridx;
		--len;
	    }
	    if (len == 0)
		return -1;    // no children, word should have ended here
	    ++wordnr;
	}

	// If the word ends we didn't find it.
	if (c == NUL)
	    return -1;

	// Perform a binary search in the list of accepted bytes.
	if (c == TAB)	    // <Tab> is handled like <Space>
	    c = ' ';
	while (byts[arridx] < c)
	{
	    // The word count is in the first idxs[] entry of the child.
	    wordnr += idxs[idxs[arridx]];
	    ++arridx;
	    if (--len == 0)	// end of the bytes, didn't find it
		return -1;
	}
	if (byts[arridx] != c)	// didn't find the byte
	    return -1;

	// Continue at the child (if there is one).
	arridx = idxs[arridx];
	++wlen;

	// One space in the good word may stand for several spaces in the
	// checked word.
	if (c == ' ')
	    while (ptr[wlen] == ' ' || ptr[wlen] == TAB)
		++wlen;
    }

    return wordnr;
}

/*
 * Return TRUE if "c1" and "c2" are similar characters according to the MAP
 * lines in the .aff file.
 */
    static int
similar_chars(slang_T *slang, int c1, int c2)
{
    int		m1, m2;
    char_u	buf[MB_MAXBYTES + 1];
    hashitem_T  *hi;

    if (c1 >= 256)
    {
	buf[mb_char2bytes(c1, buf)] = 0;
	hi = hash_find(&slang->sl_map_hash, buf);
	if (HASHITEM_EMPTY(hi))
	    m1 = 0;
	else
	    m1 = mb_ptr2char(hi->hi_key + STRLEN(hi->hi_key) + 1);
    }
    else
	m1 = slang->sl_map_array[c1];
    if (m1 == 0)
	return FALSE;


    if (c2 >= 256)
    {
	buf[mb_char2bytes(c2, buf)] = 0;
	hi = hash_find(&slang->sl_map_hash, buf);
	if (HASHITEM_EMPTY(hi))
	    m2 = 0;
	else
	    m2 = mb_ptr2char(hi->hi_key + STRLEN(hi->hi_key) + 1);
    }
    else
	m2 = slang->sl_map_array[c2];

    return m1 == m2;
}

/*
 * Add a suggestion to the list of suggestions.
 * For a suggestion that is already in the list the lowest score is remembered.
 */
    static void
add_suggestion(
    suginfo_T	*su,
    garray_T	*gap,		// either su_ga or su_sga
    char_u	*goodword,
    int		badlenarg,	// len of bad word replaced with "goodword"
    int		score,
    int		altscore,
    int		had_bonus,	// value for st_had_bonus
    slang_T	*slang,		// language for sound folding
    int		maxsf)		// su_maxscore applies to soundfold score,
				// su_sfmaxscore to the total score.
{
    int		goodlen;	// len of goodword changed
    int		badlen;		// len of bad word changed
    suggest_T   *stp;
    suggest_T   new_sug;
    int		i;
    char_u	*pgood, *pbad;

    // Minimize "badlen" for consistency.  Avoids that changing "the the" to
    // "thee the" is added next to changing the first "the" the "thee".
    pgood = goodword + STRLEN(goodword);
    pbad = su->su_badptr + badlenarg;
    for (;;)
    {
	goodlen = (int)(pgood - goodword);
	badlen = (int)(pbad - su->su_badptr);
	if (goodlen <= 0 || badlen <= 0)
	    break;
	MB_PTR_BACK(goodword, pgood);
	MB_PTR_BACK(su->su_badptr, pbad);
	if (has_mbyte)
	{
	    if (mb_ptr2char(pgood) != mb_ptr2char(pbad))
		break;
	}
	else if (*pgood != *pbad)
		break;
    }

    if (badlen == 0 && goodlen == 0)
	// goodword doesn't change anything; may happen for "the the" changing
	// the first "the" to itself.
	return;

    if (gap->ga_len == 0)
	i = -1;
    else
    {
	// Check if the word is already there.  Also check the length that is
	// being replaced "thes," -> "these" is a different suggestion from
	// "thes" -> "these".
	stp = &SUG(*gap, 0);
	for (i = gap->ga_len; --i >= 0; ++stp)
	    if (stp->st_wordlen == goodlen
		    && stp->st_orglen == badlen
		    && STRNCMP(stp->st_word, goodword, goodlen) == 0)
	    {
		// Found it.  Remember the word with the lowest score.
		if (stp->st_slang == NULL)
		    stp->st_slang = slang;

		new_sug.st_score = score;
		new_sug.st_altscore = altscore;
		new_sug.st_had_bonus = had_bonus;

		if (stp->st_had_bonus != had_bonus)
		{
		    // Only one of the two had the soundalike score computed.
		    // Need to do that for the other one now, otherwise the
		    // scores can't be compared.  This happens because
		    // suggest_try_change() doesn't compute the soundalike
		    // word to keep it fast, while some special methods set
		    // the soundalike score to zero.
		    if (had_bonus)
			rescore_one(su, stp);
		    else
		    {
			new_sug.st_word = stp->st_word;
			new_sug.st_wordlen = stp->st_wordlen;
			new_sug.st_slang = stp->st_slang;
			new_sug.st_orglen = badlen;
			rescore_one(su, &new_sug);
		    }
		}

		if (stp->st_score > new_sug.st_score)
		{
		    stp->st_score = new_sug.st_score;
		    stp->st_altscore = new_sug.st_altscore;
		    stp->st_had_bonus = new_sug.st_had_bonus;
		}
		break;
	    }
    }

    if (i < 0 && ga_grow(gap, 1) == OK)
    {
	// Add a suggestion.
	stp = &SUG(*gap, gap->ga_len);
	stp->st_word = vim_strnsave(goodword, goodlen);
	if (stp->st_word != NULL)
	{
	    stp->st_wordlen = goodlen;
	    stp->st_score = score;
	    stp->st_altscore = altscore;
	    stp->st_had_bonus = had_bonus;
	    stp->st_orglen = badlen;
	    stp->st_slang = slang;
	    ++gap->ga_len;

	    // If we have too many suggestions now, sort the list and keep
	    // the best suggestions.
	    if (gap->ga_len > SUG_MAX_COUNT(su))
	    {
		if (maxsf)
		    su->su_sfmaxscore = cleanup_suggestions(gap,
				      su->su_sfmaxscore, SUG_CLEAN_COUNT(su));
		else
		    su->su_maxscore = cleanup_suggestions(gap,
					su->su_maxscore, SUG_CLEAN_COUNT(su));
	    }
	}
    }
}

/*
 * Suggestions may in fact be flagged as errors.  Esp. for banned words and
 * for split words, such as "the the".  Remove these from the list here.
 */
    static void
check_suggestions(
    suginfo_T	*su,
    garray_T	*gap)		    // either su_ga or su_sga
{
    suggest_T   *stp;
    int		i;
    char_u	longword[MAXWLEN + 1];
    int		len;
    hlf_T	attr;

    if (gap->ga_len == 0)
	return;
    stp = &SUG(*gap, 0);
    for (i = gap->ga_len - 1; i >= 0; --i)
    {
	// Need to append what follows to check for "the the".
	vim_strncpy(longword, stp[i].st_word, MAXWLEN);
	len = stp[i].st_wordlen;
	vim_strncpy(longword + len, su->su_badptr + stp[i].st_orglen,
							       MAXWLEN - len);
	attr = HLF_COUNT;
	(void)spell_check(curwin, longword, &attr, NULL, FALSE);
	if (attr != HLF_COUNT)
	{
	    // Remove this entry.
	    vim_free(stp[i].st_word);
	    --gap->ga_len;
	    if (i < gap->ga_len)
		mch_memmove(stp + i, stp + i + 1,
				       sizeof(suggest_T) * (gap->ga_len - i));
	}
    }
}


/*
 * Add a word to be banned.
 */
    static void
add_banned(
    suginfo_T	*su,
    char_u	*word)
{
    char_u	*s;
    hash_T	hash;
    hashitem_T	*hi;

    hash = hash_hash(word);
    hi = hash_lookup(&su->su_banned, word, hash);
    if (!HASHITEM_EMPTY(hi))		// already present
	return;
    s = vim_strsave(word);
    if (s != NULL)
	hash_add_item(&su->su_banned, hi, s, hash);
}

/*
 * Recompute the score for all suggestions if sound-folding is possible.  This
 * is slow, thus only done for the final results.
 */
    static void
rescore_suggestions(suginfo_T *su)
{
    int		i;

    if (su->su_sallang != NULL)
	for (i = 0; i < su->su_ga.ga_len; ++i)
	    rescore_one(su, &SUG(su->su_ga, i));
}

/*
 * Recompute the score for one suggestion if sound-folding is possible.
 */
    static void
rescore_one(suginfo_T *su, suggest_T *stp)
{
    slang_T	*slang = stp->st_slang;
    char_u	sal_badword[MAXWLEN];
    char_u	*p;

    // Only rescore suggestions that have no sal score yet and do have a
    // language.
    if (slang != NULL && slang->sl_sal.ga_len > 0 && !stp->st_had_bonus)
    {
	if (slang == su->su_sallang)
	    p = su->su_sal_badword;
	else
	{
	    spell_soundfold(slang, su->su_fbadword, TRUE, sal_badword);
	    p = sal_badword;
	}

	stp->st_altscore = stp_sal_score(stp, su, slang, p);
	if (stp->st_altscore == SCORE_MAXMAX)
	    stp->st_altscore = SCORE_BIG;
	stp->st_score = RESCORE(stp->st_score, stp->st_altscore);
	stp->st_had_bonus = TRUE;
    }
}

static int sug_compare(const void *s1, const void *s2);

/*
 * Function given to qsort() to sort the suggestions on st_score.
 * First on "st_score", then "st_altscore" then alphabetically.
 */
    static int
sug_compare(const void *s1, const void *s2)
{
    suggest_T	*p1 = (suggest_T *)s1;
    suggest_T	*p2 = (suggest_T *)s2;
    int		n;

    n = p1->st_score == p2->st_score ? 0 :
	p1->st_score > p2->st_score ? 1 : -1;

    if (n == 0)
    {
	n = p1->st_altscore == p2->st_altscore ? 0 :
	    p1->st_altscore > p2->st_altscore ? 1 : -1;

	if (n == 0)
	    n = STRICMP(p1->st_word, p2->st_word);
    }
    return n;
}

/*
 * Cleanup the suggestions:
 * - Sort on score.
 * - Remove words that won't be displayed.
 * Returns the maximum score in the list or "maxscore" unmodified.
 */
    static int
cleanup_suggestions(
    garray_T	*gap,
    int		maxscore,
    int		keep)		// nr of suggestions to keep
{
    if (gap->ga_len <= 0)
	return maxscore;

    // Sort the list.
    qsort(gap->ga_data, (size_t)gap->ga_len, sizeof(suggest_T),
	    sug_compare);

    // Truncate the list to the number of suggestions that will be
    // displayed.
    if (gap->ga_len > keep)
    {
	int		i;
	suggest_T   *stp = &SUG(*gap, 0);

	for (i = keep; i < gap->ga_len; ++i)
	    vim_free(stp[i].st_word);
	gap->ga_len = keep;
	if (keep >= 1)
	    return stp[keep - 1].st_score;
    }
    return maxscore;
}

/*
 * Compute a score for two sound-a-like words.
 * This permits up to two inserts/deletes/swaps/etc. to keep things fast.
 * Instead of a generic loop we write out the code.  That keeps it fast by
 * avoiding checks that will not be possible.
 */
    static int
soundalike_score(
    char_u	*goodstart,	// sound-folded good word
    char_u	*badstart)	// sound-folded bad word
{
    char_u	*goodsound = goodstart;
    char_u	*badsound = badstart;
    int		goodlen;
    int		badlen;
    int		n;
    char_u	*pl, *ps;
    char_u	*pl2, *ps2;
    int		score = 0;

    // Adding/inserting "*" at the start (word starts with vowel) shouldn't be
    // counted so much, vowels halfway the word aren't counted at all.
    if ((*badsound == '*' || *goodsound == '*') && *badsound != *goodsound)
    {
	if ((badsound[0] == NUL && goodsound[1] == NUL)
	    || (goodsound[0] == NUL && badsound[1] == NUL))
	    // changing word with vowel to word without a sound
	    return SCORE_DEL;
	if (badsound[0] == NUL || goodsound[0] == NUL)
	    // more than two changes
	    return SCORE_MAXMAX;

	if (badsound[1] == goodsound[1]
		|| (badsound[1] != NUL
		    && goodsound[1] != NUL
		    && badsound[2] == goodsound[2]))
	{
	    // handle like a substitute
	}
	else
	{
	    score = 2 * SCORE_DEL / 3;
	    if (*badsound == '*')
		++badsound;
	    else
		++goodsound;
	}
    }

    goodlen = (int)STRLEN(goodsound);
    badlen = (int)STRLEN(badsound);

    // Return quickly if the lengths are too different to be fixed by two
    // changes.
    n = goodlen - badlen;
    if (n < -2 || n > 2)
	return SCORE_MAXMAX;

    if (n > 0)
    {
	pl = goodsound;	    // goodsound is longest
	ps = badsound;
    }
    else
    {
	pl = badsound;	    // badsound is longest
	ps = goodsound;
    }

    // Skip over the identical part.
    while (*pl == *ps && *pl != NUL)
    {
	++pl;
	++ps;
    }

    switch (n)
    {
	case -2:
	case 2:
	    // Must delete two characters from "pl".
	    ++pl;	// first delete
	    while (*pl == *ps)
	    {
		++pl;
		++ps;
	    }
	    // strings must be equal after second delete
	    if (STRCMP(pl + 1, ps) == 0)
		return score + SCORE_DEL * 2;

	    // Failed to compare.
	    break;

	case -1:
	case 1:
	    // Minimal one delete from "pl" required.

	    // 1: delete
	    pl2 = pl + 1;
	    ps2 = ps;
	    while (*pl2 == *ps2)
	    {
		if (*pl2 == NUL)	// reached the end
		    return score + SCORE_DEL;
		++pl2;
		++ps2;
	    }

	    // 2: delete then swap, then rest must be equal
	    if (pl2[0] == ps2[1] && pl2[1] == ps2[0]
					     && STRCMP(pl2 + 2, ps2 + 2) == 0)
		return score + SCORE_DEL + SCORE_SWAP;

	    // 3: delete then substitute, then the rest must be equal
	    if (STRCMP(pl2 + 1, ps2 + 1) == 0)
		return score + SCORE_DEL + SCORE_SUBST;

	    // 4: first swap then delete
	    if (pl[0] == ps[1] && pl[1] == ps[0])
	    {
		pl2 = pl + 2;	    // swap, skip two chars
		ps2 = ps + 2;
		while (*pl2 == *ps2)
		{
		    ++pl2;
		    ++ps2;
		}
		// delete a char and then strings must be equal
		if (STRCMP(pl2 + 1, ps2) == 0)
		    return score + SCORE_SWAP + SCORE_DEL;
	    }

	    // 5: first substitute then delete
	    pl2 = pl + 1;	    // substitute, skip one char
	    ps2 = ps + 1;
	    while (*pl2 == *ps2)
	    {
		++pl2;
		++ps2;
	    }
	    // delete a char and then strings must be equal
	    if (STRCMP(pl2 + 1, ps2) == 0)
		return score + SCORE_SUBST + SCORE_DEL;

	    // Failed to compare.
	    break;

	case 0:
	    // Lengths are equal, thus changes must result in same length: An
	    // insert is only possible in combination with a delete.
	    // 1: check if for identical strings
	    if (*pl == NUL)
		return score;

	    // 2: swap
	    if (pl[0] == ps[1] && pl[1] == ps[0])
	    {
		pl2 = pl + 2;	    // swap, skip two chars
		ps2 = ps + 2;
		while (*pl2 == *ps2)
		{
		    if (*pl2 == NUL)	// reached the end
			return score + SCORE_SWAP;
		    ++pl2;
		    ++ps2;
		}
		// 3: swap and swap again
		if (pl2[0] == ps2[1] && pl2[1] == ps2[0]
					     && STRCMP(pl2 + 2, ps2 + 2) == 0)
		    return score + SCORE_SWAP + SCORE_SWAP;

		// 4: swap and substitute
		if (STRCMP(pl2 + 1, ps2 + 1) == 0)
		    return score + SCORE_SWAP + SCORE_SUBST;
	    }

	    // 5: substitute
	    pl2 = pl + 1;
	    ps2 = ps + 1;
	    while (*pl2 == *ps2)
	    {
		if (*pl2 == NUL)	// reached the end
		    return score + SCORE_SUBST;
		++pl2;
		++ps2;
	    }

	    // 6: substitute and swap
	    if (pl2[0] == ps2[1] && pl2[1] == ps2[0]
					     && STRCMP(pl2 + 2, ps2 + 2) == 0)
		return score + SCORE_SUBST + SCORE_SWAP;

	    // 7: substitute and substitute
	    if (STRCMP(pl2 + 1, ps2 + 1) == 0)
		return score + SCORE_SUBST + SCORE_SUBST;

	    // 8: insert then delete
	    pl2 = pl;
	    ps2 = ps + 1;
	    while (*pl2 == *ps2)
	    {
		++pl2;
		++ps2;
	    }
	    if (STRCMP(pl2 + 1, ps2) == 0)
		return score + SCORE_INS + SCORE_DEL;

	    // 9: delete then insert
	    pl2 = pl + 1;
	    ps2 = ps;
	    while (*pl2 == *ps2)
	    {
		++pl2;
		++ps2;
	    }
	    if (STRCMP(pl2, ps2 + 1) == 0)
		return score + SCORE_INS + SCORE_DEL;

	    // Failed to compare.
	    break;
    }

    return SCORE_MAXMAX;
}

/*
 * Compute the "edit distance" to turn "badword" into "goodword".  The less
 * deletes/inserts/substitutes/swaps are required the lower the score.
 *
 * The algorithm is described by Du and Chang, 1992.
 * The implementation of the algorithm comes from Aspell editdist.cpp,
 * edit_distance().  It has been converted from C++ to C and modified to
 * support multi-byte characters.
 */
    static int
spell_edit_score(
    slang_T	*slang,
    char_u	*badword,
    char_u	*goodword)
{
    int		*cnt;
    int		badlen, goodlen;	// lengths including NUL
    int		j, i;
    int		t;
    int		bc, gc;
    int		pbc, pgc;
    char_u	*p;
    int		wbadword[MAXWLEN];
    int		wgoodword[MAXWLEN];

    if (has_mbyte)
    {
	// Get the characters from the multi-byte strings and put them in an
	// int array for easy access.
	for (p = badword, badlen = 0; *p != NUL; )
	    wbadword[badlen++] = mb_cptr2char_adv(&p);
	wbadword[badlen++] = 0;
	for (p = goodword, goodlen = 0; *p != NUL; )
	    wgoodword[goodlen++] = mb_cptr2char_adv(&p);
	wgoodword[goodlen++] = 0;
    }
    else
    {
	badlen = (int)STRLEN(badword) + 1;
	goodlen = (int)STRLEN(goodword) + 1;
    }

    // We use "cnt" as an array: CNT(badword_idx, goodword_idx).
#define CNT(a, b)   cnt[(a) + (b) * (badlen + 1)]
    cnt = ALLOC_MULT(int, (badlen + 1) * (goodlen + 1));
    if (cnt == NULL)
	return 0;	// out of memory

    CNT(0, 0) = 0;
    for (j = 1; j <= goodlen; ++j)
	CNT(0, j) = CNT(0, j - 1) + SCORE_INS;

    for (i = 1; i <= badlen; ++i)
    {
	CNT(i, 0) = CNT(i - 1, 0) + SCORE_DEL;
	for (j = 1; j <= goodlen; ++j)
	{
	    if (has_mbyte)
	    {
		bc = wbadword[i - 1];
		gc = wgoodword[j - 1];
	    }
	    else
	    {
		bc = badword[i - 1];
		gc = goodword[j - 1];
	    }
	    if (bc == gc)
		CNT(i, j) = CNT(i - 1, j - 1);
	    else
	    {
		// Use a better score when there is only a case difference.
		if (SPELL_TOFOLD(bc) == SPELL_TOFOLD(gc))
		    CNT(i, j) = SCORE_ICASE + CNT(i - 1, j - 1);
		else
		{
		    // For a similar character use SCORE_SIMILAR.
		    if (slang != NULL
			    && slang->sl_has_map
			    && similar_chars(slang, gc, bc))
			CNT(i, j) = SCORE_SIMILAR + CNT(i - 1, j - 1);
		    else
			CNT(i, j) = SCORE_SUBST + CNT(i - 1, j - 1);
		}

		if (i > 1 && j > 1)
		{
		    if (has_mbyte)
		    {
			pbc = wbadword[i - 2];
			pgc = wgoodword[j - 2];
		    }
		    else
		    {
			pbc = badword[i - 2];
			pgc = goodword[j - 2];
		    }
		    if (bc == pgc && pbc == gc)
		    {
			t = SCORE_SWAP + CNT(i - 2, j - 2);
			if (t < CNT(i, j))
			    CNT(i, j) = t;
		    }
		}
		t = SCORE_DEL + CNT(i - 1, j);
		if (t < CNT(i, j))
		    CNT(i, j) = t;
		t = SCORE_INS + CNT(i, j - 1);
		if (t < CNT(i, j))
		    CNT(i, j) = t;
	    }
	}
    }

    i = CNT(badlen - 1, goodlen - 1);
    vim_free(cnt);
    return i;
}

typedef struct
{
    int		badi;
    int		goodi;
    int		score;
} limitscore_T;

/*
 * Like spell_edit_score(), but with a limit on the score to make it faster.
 * May return SCORE_MAXMAX when the score is higher than "limit".
 *
 * This uses a stack for the edits still to be tried.
 * The idea comes from Aspell leditdist.cpp.  Rewritten in C and added support
 * for multi-byte characters.
 */
    static int
spell_edit_score_limit(
    slang_T	*slang,
    char_u	*badword,
    char_u	*goodword,
    int		limit)
{
    limitscore_T    stack[10];		// allow for over 3 * 2 edits
    int		    stackidx;
    int		    bi, gi;
    int		    bi2, gi2;
    int		    bc, gc;
    int		    score;
    int		    score_off;
    int		    minscore;
    int		    round;

    // Multi-byte characters require a bit more work, use a different function
    // to avoid testing "has_mbyte" quite often.
    if (has_mbyte)
	return spell_edit_score_limit_w(slang, badword, goodword, limit);

    // The idea is to go from start to end over the words.  So long as
    // characters are equal just continue, this always gives the lowest score.
    // When there is a difference try several alternatives.  Each alternative
    // increases "score" for the edit distance.  Some of the alternatives are
    // pushed unto a stack and tried later, some are tried right away.  At the
    // end of the word the score for one alternative is known.  The lowest
    // possible score is stored in "minscore".
    stackidx = 0;
    bi = 0;
    gi = 0;
    score = 0;
    minscore = limit + 1;

    for (;;)
    {
	// Skip over an equal part, score remains the same.
	for (;;)
	{
	    bc = badword[bi];
	    gc = goodword[gi];
	    if (bc != gc)	// stop at a char that's different
		break;
	    if (bc == NUL)	// both words end
	    {
		if (score < minscore)
		    minscore = score;
		goto pop;	// do next alternative
	    }
	    ++bi;
	    ++gi;
	}

	if (gc == NUL)    // goodword ends, delete badword chars
	{
	    do
	    {
		if ((score += SCORE_DEL) >= minscore)
		    goto pop;	    // do next alternative
	    } while (badword[++bi] != NUL);
	    minscore = score;
	}
	else if (bc == NUL) // badword ends, insert badword chars
	{
	    do
	    {
		if ((score += SCORE_INS) >= minscore)
		    goto pop;	    // do next alternative
	    } while (goodword[++gi] != NUL);
	    minscore = score;
	}
	else			// both words continue
	{
	    // If not close to the limit, perform a change.  Only try changes
	    // that may lead to a lower score than "minscore".
	    // round 0: try deleting a char from badword
	    // round 1: try inserting a char in badword
	    for (round = 0; round <= 1; ++round)
	    {
		score_off = score + (round == 0 ? SCORE_DEL : SCORE_INS);
		if (score_off < minscore)
		{
		    if (score_off + SCORE_EDIT_MIN >= minscore)
		    {
			// Near the limit, rest of the words must match.  We
			// can check that right now, no need to push an item
			// onto the stack.
			bi2 = bi + 1 - round;
			gi2 = gi + round;
			while (goodword[gi2] == badword[bi2])
			{
			    if (goodword[gi2] == NUL)
			    {
				minscore = score_off;
				break;
			    }
			    ++bi2;
			    ++gi2;
			}
		    }
		    else
		    {
			// try deleting/inserting a character later
			stack[stackidx].badi = bi + 1 - round;
			stack[stackidx].goodi = gi + round;
			stack[stackidx].score = score_off;
			++stackidx;
		    }
		}
	    }

	    if (score + SCORE_SWAP < minscore)
	    {
		// If swapping two characters makes a match then the
		// substitution is more expensive, thus there is no need to
		// try both.
		if (gc == badword[bi + 1] && bc == goodword[gi + 1])
		{
		    // Swap two characters, that is: skip them.
		    gi += 2;
		    bi += 2;
		    score += SCORE_SWAP;
		    continue;
		}
	    }

	    // Substitute one character for another which is the same
	    // thing as deleting a character from both goodword and badword.
	    // Use a better score when there is only a case difference.
	    if (SPELL_TOFOLD(bc) == SPELL_TOFOLD(gc))
		score += SCORE_ICASE;
	    else
	    {
		// For a similar character use SCORE_SIMILAR.
		if (slang != NULL
			&& slang->sl_has_map
			&& similar_chars(slang, gc, bc))
		    score += SCORE_SIMILAR;
		else
		    score += SCORE_SUBST;
	    }

	    if (score < minscore)
	    {
		// Do the substitution.
		++gi;
		++bi;
		continue;
	    }
	}
pop:
	// Get here to try the next alternative, pop it from the stack.
	if (stackidx == 0)		// stack is empty, finished
	    break;

	// pop an item from the stack
	--stackidx;
	gi = stack[stackidx].goodi;
	bi = stack[stackidx].badi;
	score = stack[stackidx].score;
    }

    // When the score goes over "limit" it may actually be much higher.
    // Return a very large number to avoid going below the limit when giving a
    // bonus.
    if (minscore > limit)
	return SCORE_MAXMAX;
    return minscore;
}

/*
 * Multi-byte version of spell_edit_score_limit().
 * Keep it in sync with the above!
 */
    static int
spell_edit_score_limit_w(
    slang_T	*slang,
    char_u	*badword,
    char_u	*goodword,
    int		limit)
{
    limitscore_T    stack[10];		// allow for over 3 * 2 edits
    int		    stackidx;
    int		    bi, gi;
    int		    bi2, gi2;
    int		    bc, gc;
    int		    score;
    int		    score_off;
    int		    minscore;
    int		    round;
    char_u	    *p;
    int		    wbadword[MAXWLEN];
    int		    wgoodword[MAXWLEN];

    // Get the characters from the multi-byte strings and put them in an
    // int array for easy access.
    bi = 0;
    for (p = badword; *p != NUL; )
	wbadword[bi++] = mb_cptr2char_adv(&p);
    wbadword[bi++] = 0;
    gi = 0;
    for (p = goodword; *p != NUL; )
	wgoodword[gi++] = mb_cptr2char_adv(&p);
    wgoodword[gi++] = 0;

    // The idea is to go from start to end over the words.  So long as
    // characters are equal just continue, this always gives the lowest score.
    // When there is a difference try several alternatives.  Each alternative
    // increases "score" for the edit distance.  Some of the alternatives are
    // pushed unto a stack and tried later, some are tried right away.  At the
    // end of the word the score for one alternative is known.  The lowest
    // possible score is stored in "minscore".
    stackidx = 0;
    bi = 0;
    gi = 0;
    score = 0;
    minscore = limit + 1;

    for (;;)
    {
	// Skip over an equal part, score remains the same.
	for (;;)
	{
	    bc = wbadword[bi];
	    gc = wgoodword[gi];

	    if (bc != gc)	// stop at a char that's different
		break;
	    if (bc == NUL)	// both words end
	    {
		if (score < minscore)
		    minscore = score;
		goto pop;	// do next alternative
	    }
	    ++bi;
	    ++gi;
	}

	if (gc == NUL)    // goodword ends, delete badword chars
	{
	    do
	    {
		if ((score += SCORE_DEL) >= minscore)
		    goto pop;	    // do next alternative
	    } while (wbadword[++bi] != NUL);
	    minscore = score;
	}
	else if (bc == NUL) // badword ends, insert badword chars
	{
	    do
	    {
		if ((score += SCORE_INS) >= minscore)
		    goto pop;	    // do next alternative
	    } while (wgoodword[++gi] != NUL);
	    minscore = score;
	}
	else			// both words continue
	{
	    // If not close to the limit, perform a change.  Only try changes
	    // that may lead to a lower score than "minscore".
	    // round 0: try deleting a char from badword
	    // round 1: try inserting a char in badword
	    for (round = 0; round <= 1; ++round)
	    {
		score_off = score + (round == 0 ? SCORE_DEL : SCORE_INS);
		if (score_off < minscore)
		{
		    if (score_off + SCORE_EDIT_MIN >= minscore)
		    {
			// Near the limit, rest of the words must match.  We
			// can check that right now, no need to push an item
			// onto the stack.
			bi2 = bi + 1 - round;
			gi2 = gi + round;
			while (wgoodword[gi2] == wbadword[bi2])
			{
			    if (wgoodword[gi2] == NUL)
			    {
				minscore = score_off;
				break;
			    }
			    ++bi2;
			    ++gi2;
			}
		    }
		    else
		    {
			// try deleting a character from badword later
			stack[stackidx].badi = bi + 1 - round;
			stack[stackidx].goodi = gi + round;
			stack[stackidx].score = score_off;
			++stackidx;
		    }
		}
	    }

	    if (score + SCORE_SWAP < minscore)
	    {
		// If swapping two characters makes a match then the
		// substitution is more expensive, thus there is no need to
		// try both.
		if (gc == wbadword[bi + 1] && bc == wgoodword[gi + 1])
		{
		    // Swap two characters, that is: skip them.
		    gi += 2;
		    bi += 2;
		    score += SCORE_SWAP;
		    continue;
		}
	    }

	    // Substitute one character for another which is the same
	    // thing as deleting a character from both goodword and badword.
	    // Use a better score when there is only a case difference.
	    if (SPELL_TOFOLD(bc) == SPELL_TOFOLD(gc))
		score += SCORE_ICASE;
	    else
	    {
		// For a similar character use SCORE_SIMILAR.
		if (slang != NULL
			&& slang->sl_has_map
			&& similar_chars(slang, gc, bc))
		    score += SCORE_SIMILAR;
		else
		    score += SCORE_SUBST;
	    }

	    if (score < minscore)
	    {
		// Do the substitution.
		++gi;
		++bi;
		continue;
	    }
	}
pop:
	// Get here to try the next alternative, pop it from the stack.
	if (stackidx == 0)		// stack is empty, finished
	    break;

	// pop an item from the stack
	--stackidx;
	gi = stack[stackidx].goodi;
	bi = stack[stackidx].badi;
	score = stack[stackidx].score;
    }

    // When the score goes over "limit" it may actually be much higher.
    // Return a very large number to avoid going below the limit when giving a
    // bonus.
    if (minscore > limit)
	return SCORE_MAXMAX;
    return minscore;
}
#endif  // FEAT_SPELL