aboutsummaryrefslogtreecommitdiffstats
path: root/gcc-4.9/gcc/sel-sched-ir.c
blob: e1408b488a6353535112eebbffece91690bf6bad (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
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212
5213
5214
5215
5216
5217
5218
5219
5220
5221
5222
5223
5224
5225
5226
5227
5228
5229
5230
5231
5232
5233
5234
5235
5236
5237
5238
5239
5240
5241
5242
5243
5244
5245
5246
5247
5248
5249
5250
5251
5252
5253
5254
5255
5256
5257
5258
5259
5260
5261
5262
5263
5264
5265
5266
5267
5268
5269
5270
5271
5272
5273
5274
5275
5276
5277
5278
5279
5280
5281
5282
5283
5284
5285
5286
5287
5288
5289
5290
5291
5292
5293
5294
5295
5296
5297
5298
5299
5300
5301
5302
5303
5304
5305
5306
5307
5308
5309
5310
5311
5312
5313
5314
5315
5316
5317
5318
5319
5320
5321
5322
5323
5324
5325
5326
5327
5328
5329
5330
5331
5332
5333
5334
5335
5336
5337
5338
5339
5340
5341
5342
5343
5344
5345
5346
5347
5348
5349
5350
5351
5352
5353
5354
5355
5356
5357
5358
5359
5360
5361
5362
5363
5364
5365
5366
5367
5368
5369
5370
5371
5372
5373
5374
5375
5376
5377
5378
5379
5380
5381
5382
5383
5384
5385
5386
5387
5388
5389
5390
5391
5392
5393
5394
5395
5396
5397
5398
5399
5400
5401
5402
5403
5404
5405
5406
5407
5408
5409
5410
5411
5412
5413
5414
5415
5416
5417
5418
5419
5420
5421
5422
5423
5424
5425
5426
5427
5428
5429
5430
5431
5432
5433
5434
5435
5436
5437
5438
5439
5440
5441
5442
5443
5444
5445
5446
5447
5448
5449
5450
5451
5452
5453
5454
5455
5456
5457
5458
5459
5460
5461
5462
5463
5464
5465
5466
5467
5468
5469
5470
5471
5472
5473
5474
5475
5476
5477
5478
5479
5480
5481
5482
5483
5484
5485
5486
5487
5488
5489
5490
5491
5492
5493
5494
5495
5496
5497
5498
5499
5500
5501
5502
5503
5504
5505
5506
5507
5508
5509
5510
5511
5512
5513
5514
5515
5516
5517
5518
5519
5520
5521
5522
5523
5524
5525
5526
5527
5528
5529
5530
5531
5532
5533
5534
5535
5536
5537
5538
5539
5540
5541
5542
5543
5544
5545
5546
5547
5548
5549
5550
5551
5552
5553
5554
5555
5556
5557
5558
5559
5560
5561
5562
5563
5564
5565
5566
5567
5568
5569
5570
5571
5572
5573
5574
5575
5576
5577
5578
5579
5580
5581
5582
5583
5584
5585
5586
5587
5588
5589
5590
5591
5592
5593
5594
5595
5596
5597
5598
5599
5600
5601
5602
5603
5604
5605
5606
5607
5608
5609
5610
5611
5612
5613
5614
5615
5616
5617
5618
5619
5620
5621
5622
5623
5624
5625
5626
5627
5628
5629
5630
5631
5632
5633
5634
5635
5636
5637
5638
5639
5640
5641
5642
5643
5644
5645
5646
5647
5648
5649
5650
5651
5652
5653
5654
5655
5656
5657
5658
5659
5660
5661
5662
5663
5664
5665
5666
5667
5668
5669
5670
5671
5672
5673
5674
5675
5676
5677
5678
5679
5680
5681
5682
5683
5684
5685
5686
5687
5688
5689
5690
5691
5692
5693
5694
5695
5696
5697
5698
5699
5700
5701
5702
5703
5704
5705
5706
5707
5708
5709
5710
5711
5712
5713
5714
5715
5716
5717
5718
5719
5720
5721
5722
5723
5724
5725
5726
5727
5728
5729
5730
5731
5732
5733
5734
5735
5736
5737
5738
5739
5740
5741
5742
5743
5744
5745
5746
5747
5748
5749
5750
5751
5752
5753
5754
5755
5756
5757
5758
5759
5760
5761
5762
5763
5764
5765
5766
5767
5768
5769
5770
5771
5772
5773
5774
5775
5776
5777
5778
5779
5780
5781
5782
5783
5784
5785
5786
5787
5788
5789
5790
5791
5792
5793
5794
5795
5796
5797
5798
5799
5800
5801
5802
5803
5804
5805
5806
5807
5808
5809
5810
5811
5812
5813
5814
5815
5816
5817
5818
5819
5820
5821
5822
5823
5824
5825
5826
5827
5828
5829
5830
5831
5832
5833
5834
5835
5836
5837
5838
5839
5840
5841
5842
5843
5844
5845
5846
5847
5848
5849
5850
5851
5852
5853
5854
5855
5856
5857
5858
5859
5860
5861
5862
5863
5864
5865
5866
5867
5868
5869
5870
5871
5872
5873
5874
5875
5876
5877
5878
5879
5880
5881
5882
5883
5884
5885
5886
5887
5888
5889
5890
5891
5892
5893
5894
5895
5896
5897
5898
5899
5900
5901
5902
5903
5904
5905
5906
5907
5908
5909
5910
5911
5912
5913
5914
5915
5916
5917
5918
5919
5920
5921
5922
5923
5924
5925
5926
5927
5928
5929
5930
5931
5932
5933
5934
5935
5936
5937
5938
5939
5940
5941
5942
5943
5944
5945
5946
5947
5948
5949
5950
5951
5952
5953
5954
5955
5956
5957
5958
5959
5960
5961
5962
5963
5964
5965
5966
5967
5968
5969
5970
5971
5972
5973
5974
5975
5976
5977
5978
5979
5980
5981
5982
5983
5984
5985
5986
5987
5988
5989
5990
5991
5992
5993
5994
5995
5996
5997
5998
5999
6000
6001
6002
6003
6004
6005
6006
6007
6008
6009
6010
6011
6012
6013
6014
6015
6016
6017
6018
6019
6020
6021
6022
6023
6024
6025
6026
6027
6028
6029
6030
6031
6032
6033
6034
6035
6036
6037
6038
6039
6040
6041
6042
6043
6044
6045
6046
6047
6048
6049
6050
6051
6052
6053
6054
6055
6056
6057
6058
6059
6060
6061
6062
6063
6064
6065
6066
6067
6068
6069
6070
6071
6072
6073
6074
6075
6076
6077
6078
6079
6080
6081
6082
6083
6084
6085
6086
6087
6088
6089
6090
6091
6092
6093
6094
6095
6096
6097
6098
6099
6100
6101
6102
6103
6104
6105
6106
6107
6108
6109
6110
6111
6112
6113
6114
6115
6116
6117
6118
6119
6120
6121
6122
6123
6124
6125
6126
6127
6128
6129
6130
6131
6132
6133
6134
6135
6136
6137
6138
6139
6140
6141
6142
6143
6144
6145
6146
6147
6148
6149
6150
6151
6152
6153
6154
6155
6156
6157
6158
6159
6160
6161
6162
6163
6164
6165
6166
6167
6168
6169
6170
6171
6172
6173
6174
6175
6176
6177
6178
6179
6180
6181
6182
6183
6184
6185
6186
6187
6188
6189
6190
6191
6192
6193
6194
6195
6196
6197
6198
6199
6200
6201
6202
6203
6204
6205
6206
6207
6208
6209
6210
6211
6212
6213
6214
6215
6216
6217
6218
6219
6220
6221
6222
6223
6224
6225
6226
6227
6228
6229
6230
6231
6232
6233
6234
6235
6236
6237
6238
6239
6240
6241
6242
6243
6244
6245
6246
6247
6248
6249
6250
6251
6252
6253
6254
6255
6256
6257
6258
6259
6260
6261
6262
6263
6264
6265
6266
6267
6268
6269
6270
6271
6272
6273
6274
6275
6276
6277
6278
6279
6280
6281
6282
6283
6284
6285
6286
6287
6288
6289
6290
6291
6292
6293
6294
6295
6296
6297
6298
6299
6300
6301
6302
6303
6304
6305
6306
6307
6308
6309
6310
6311
6312
6313
6314
6315
6316
6317
6318
6319
6320
6321
6322
6323
6324
6325
6326
6327
6328
6329
6330
6331
6332
6333
6334
6335
6336
6337
6338
6339
6340
6341
6342
6343
6344
6345
6346
6347
6348
6349
6350
6351
6352
6353
6354
6355
6356
6357
6358
6359
6360
6361
6362
6363
6364
6365
6366
6367
6368
6369
6370
6371
6372
6373
6374
6375
6376
6377
6378
6379
6380
6381
6382
6383
6384
6385
6386
6387
6388
6389
6390
6391
6392
6393
6394
6395
6396
6397
6398
6399
6400
6401
6402
6403
6404
6405
6406
6407
6408
6409
6410
6411
6412
6413
6414
6415
6416
6417
6418
6419
6420
6421
6422
6423
6424
6425
6426
6427
6428
6429
6430
6431
6432
6433
6434
6435
6436
6437
6438
6439
6440
6441
6442
6443
6444
6445
6446
6447
6448
6449
/* Instruction scheduling pass.  Selective scheduler and pipeliner.
   Copyright (C) 2006-2014 Free Software Foundation, Inc.

This file is part of GCC.

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

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

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

#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "diagnostic-core.h"
#include "rtl.h"
#include "tm_p.h"
#include "hard-reg-set.h"
#include "regs.h"
#include "function.h"
#include "flags.h"
#include "insn-config.h"
#include "insn-attr.h"
#include "except.h"
#include "recog.h"
#include "params.h"
#include "target.h"
#include "sched-int.h"
#include "ggc.h"
#include "tree.h"
#include "vec.h"
#include "langhooks.h"
#include "rtlhooks-def.h"
#include "emit-rtl.h"  /* FIXME: Can go away once crtl is moved to rtl.h.  */

#ifdef INSN_SCHEDULING
#include "sel-sched-ir.h"
/* We don't have to use it except for sel_print_insn.  */
#include "sel-sched-dump.h"

/* A vector holding bb info for whole scheduling pass.  */
vec<sel_global_bb_info_def>
    sel_global_bb_info = vNULL;

/* A vector holding bb info.  */
vec<sel_region_bb_info_def>
    sel_region_bb_info = vNULL;

/* A pool for allocating all lists.  */
alloc_pool sched_lists_pool;

/* This contains information about successors for compute_av_set.  */
struct succs_info current_succs;

/* Data structure to describe interaction with the generic scheduler utils.  */
static struct common_sched_info_def sel_common_sched_info;

/* The loop nest being pipelined.  */
struct loop *current_loop_nest;

/* LOOP_NESTS is a vector containing the corresponding loop nest for
   each region.  */
static vec<loop_p> loop_nests = vNULL;

/* Saves blocks already in loop regions, indexed by bb->index.  */
static sbitmap bbs_in_loop_rgns = NULL;

/* CFG hooks that are saved before changing create_basic_block hook.  */
static struct cfg_hooks orig_cfg_hooks;


/* Array containing reverse topological index of function basic blocks,
   indexed by BB->INDEX.  */
static int *rev_top_order_index = NULL;

/* Length of the above array.  */
static int rev_top_order_index_len = -1;

/* A regset pool structure.  */
static struct
{
  /* The stack to which regsets are returned.  */
  regset *v;

  /* Its pointer.  */
  int n;

  /* Its size.  */
  int s;

  /* In VV we save all generated regsets so that, when destructing the
     pool, we can compare it with V and check that every regset was returned
     back to pool.  */
  regset *vv;

  /* The pointer of VV stack.  */
  int nn;

  /* Its size.  */
  int ss;

  /* The difference between allocated and returned regsets.  */
  int diff;
} regset_pool = { NULL, 0, 0, NULL, 0, 0, 0 };

/* This represents the nop pool.  */
static struct
{
  /* The vector which holds previously emitted nops.  */
  insn_t *v;

  /* Its pointer.  */
  int n;

  /* Its size.  */
  int s;
} nop_pool = { NULL, 0, 0 };

/* The pool for basic block notes.  */
static rtx_vec_t bb_note_pool;

/* A NOP pattern used to emit placeholder insns.  */
rtx nop_pattern = NULL_RTX;
/* A special instruction that resides in EXIT_BLOCK.
   EXIT_INSN is successor of the insns that lead to EXIT_BLOCK.  */
rtx exit_insn = NULL_RTX;

/* TRUE if while scheduling current region, which is loop, its preheader
   was removed.  */
bool preheader_removed = false;


/* Forward static declarations.  */
static void fence_clear (fence_t);

static void deps_init_id (idata_t, insn_t, bool);
static void init_id_from_df (idata_t, insn_t, bool);
static expr_t set_insn_init (expr_t, vinsn_t, int);

static void cfg_preds (basic_block, insn_t **, int *);
static void prepare_insn_expr (insn_t, int);
static void free_history_vect (vec<expr_history_def> &);

static void move_bb_info (basic_block, basic_block);
static void remove_empty_bb (basic_block, bool);
static void sel_merge_blocks (basic_block, basic_block);
static void sel_remove_loop_preheader (void);
static bool bb_has_removable_jump_to_p (basic_block, basic_block);

static bool insn_is_the_only_one_in_bb_p (insn_t);
static void create_initial_data_sets (basic_block);

static void free_av_set (basic_block);
static void invalidate_av_set (basic_block);
static void extend_insn_data (void);
static void sel_init_new_insn (insn_t, int, int = -1);
static void finish_insns (void);

/* Various list functions.  */

/* Copy an instruction list L.  */
ilist_t
ilist_copy (ilist_t l)
{
  ilist_t head = NULL, *tailp = &head;

  while (l)
    {
      ilist_add (tailp, ILIST_INSN (l));
      tailp = &ILIST_NEXT (*tailp);
      l = ILIST_NEXT (l);
    }

  return head;
}

/* Invert an instruction list L.  */
ilist_t
ilist_invert (ilist_t l)
{
  ilist_t res = NULL;

  while (l)
    {
      ilist_add (&res, ILIST_INSN (l));
      l = ILIST_NEXT (l);
    }

  return res;
}

/* Add a new boundary to the LP list with parameters TO, PTR, and DC.  */
void
blist_add (blist_t *lp, insn_t to, ilist_t ptr, deps_t dc)
{
  bnd_t bnd;

  _list_add (lp);
  bnd = BLIST_BND (*lp);

  BND_TO (bnd) = to;
  BND_PTR (bnd) = ptr;
  BND_AV (bnd) = NULL;
  BND_AV1 (bnd) = NULL;
  BND_DC (bnd) = dc;
}

/* Remove the list note pointed to by LP.  */
void
blist_remove (blist_t *lp)
{
  bnd_t b = BLIST_BND (*lp);

  av_set_clear (&BND_AV (b));
  av_set_clear (&BND_AV1 (b));
  ilist_clear (&BND_PTR (b));

  _list_remove (lp);
}

/* Init a fence tail L.  */
void
flist_tail_init (flist_tail_t l)
{
  FLIST_TAIL_HEAD (l) = NULL;
  FLIST_TAIL_TAILP (l) = &FLIST_TAIL_HEAD (l);
}

/* Try to find fence corresponding to INSN in L.  */
fence_t
flist_lookup (flist_t l, insn_t insn)
{
  while (l)
    {
      if (FENCE_INSN (FLIST_FENCE (l)) == insn)
	return FLIST_FENCE (l);

      l = FLIST_NEXT (l);
    }

  return NULL;
}

/* Init the fields of F before running fill_insns.  */
static void
init_fence_for_scheduling (fence_t f)
{
  FENCE_BNDS (f) = NULL;
  FENCE_PROCESSED_P (f) = false;
  FENCE_SCHEDULED_P (f) = false;
}

/* Add new fence consisting of INSN and STATE to the list pointed to by LP.  */
static void
flist_add (flist_t *lp, insn_t insn, state_t state, deps_t dc, void *tc,
           insn_t last_scheduled_insn, vec<rtx, va_gc> *executing_insns,
           int *ready_ticks, int ready_ticks_size, insn_t sched_next,
           int cycle, int cycle_issued_insns, int issue_more,
           bool starts_cycle_p, bool after_stall_p)
{
  fence_t f;

  _list_add (lp);
  f = FLIST_FENCE (*lp);

  FENCE_INSN (f) = insn;

  gcc_assert (state != NULL);
  FENCE_STATE (f) = state;

  FENCE_CYCLE (f) = cycle;
  FENCE_ISSUED_INSNS (f) = cycle_issued_insns;
  FENCE_STARTS_CYCLE_P (f) = starts_cycle_p;
  FENCE_AFTER_STALL_P (f) = after_stall_p;

  gcc_assert (dc != NULL);
  FENCE_DC (f) = dc;

  gcc_assert (tc != NULL || targetm.sched.alloc_sched_context == NULL);
  FENCE_TC (f) = tc;

  FENCE_LAST_SCHEDULED_INSN (f) = last_scheduled_insn;
  FENCE_ISSUE_MORE (f) = issue_more;
  FENCE_EXECUTING_INSNS (f) = executing_insns;
  FENCE_READY_TICKS (f) = ready_ticks;
  FENCE_READY_TICKS_SIZE (f) = ready_ticks_size;
  FENCE_SCHED_NEXT (f) = sched_next;

  init_fence_for_scheduling (f);
}

/* Remove the head node of the list pointed to by LP.  */
static void
flist_remove (flist_t *lp)
{
  if (FENCE_INSN (FLIST_FENCE (*lp)))
    fence_clear (FLIST_FENCE (*lp));
  _list_remove (lp);
}

/* Clear the fence list pointed to by LP.  */
void
flist_clear (flist_t *lp)
{
  while (*lp)
    flist_remove (lp);
}

/* Add ORIGINAL_INSN the def list DL honoring CROSSES_CALL.  */
void
def_list_add (def_list_t *dl, insn_t original_insn, bool crosses_call)
{
  def_t d;

  _list_add (dl);
  d = DEF_LIST_DEF (*dl);

  d->orig_insn = original_insn;
  d->crosses_call = crosses_call;
}


/* Functions to work with target contexts.  */

/* Bulk target context.  It is convenient for debugging purposes to ensure
   that there are no uninitialized (null) target contexts.  */
static tc_t bulk_tc = (tc_t) 1;

/* Target hooks wrappers.  In the future we can provide some default
   implementations for them.  */

/* Allocate a store for the target context.  */
static tc_t
alloc_target_context (void)
{
  return (targetm.sched.alloc_sched_context
	  ? targetm.sched.alloc_sched_context () : bulk_tc);
}

/* Init target context TC.
   If CLEAN_P is true, then make TC as it is beginning of the scheduler.
   Overwise, copy current backend context to TC.  */
static void
init_target_context (tc_t tc, bool clean_p)
{
  if (targetm.sched.init_sched_context)
    targetm.sched.init_sched_context (tc, clean_p);
}

/* Allocate and initialize a target context.  Meaning of CLEAN_P is the same as
   int init_target_context ().  */
tc_t
create_target_context (bool clean_p)
{
  tc_t tc = alloc_target_context ();

  init_target_context (tc, clean_p);
  return tc;
}

/* Copy TC to the current backend context.  */
void
set_target_context (tc_t tc)
{
  if (targetm.sched.set_sched_context)
    targetm.sched.set_sched_context (tc);
}

/* TC is about to be destroyed.  Free any internal data.  */
static void
clear_target_context (tc_t tc)
{
  if (targetm.sched.clear_sched_context)
    targetm.sched.clear_sched_context (tc);
}

/*  Clear and free it.  */
static void
delete_target_context (tc_t tc)
{
  clear_target_context (tc);

  if (targetm.sched.free_sched_context)
    targetm.sched.free_sched_context (tc);
}

/* Make a copy of FROM in TO.
   NB: May be this should be a hook.  */
static void
copy_target_context (tc_t to, tc_t from)
{
  tc_t tmp = create_target_context (false);

  set_target_context (from);
  init_target_context (to, false);

  set_target_context (tmp);
  delete_target_context (tmp);
}

/* Create a copy of TC.  */
static tc_t
create_copy_of_target_context (tc_t tc)
{
  tc_t copy = alloc_target_context ();

  copy_target_context (copy, tc);

  return copy;
}

/* Clear TC and initialize it according to CLEAN_P.  The meaning of CLEAN_P
   is the same as in init_target_context ().  */
void
reset_target_context (tc_t tc, bool clean_p)
{
  clear_target_context (tc);
  init_target_context (tc, clean_p);
}

/* Functions to work with dependence contexts.
   Dc (aka deps context, aka deps_t, aka struct deps_desc *) is short for dependence
   context.  It accumulates information about processed insns to decide if
   current insn is dependent on the processed ones.  */

/* Make a copy of FROM in TO.  */
static void
copy_deps_context (deps_t to, deps_t from)
{
  init_deps (to, false);
  deps_join (to, from);
}

/* Allocate store for dep context.  */
static deps_t
alloc_deps_context (void)
{
  return XNEW (struct deps_desc);
}

/* Allocate and initialize dep context.  */
static deps_t
create_deps_context (void)
{
  deps_t dc = alloc_deps_context ();

  init_deps (dc, false);
  return dc;
}

/* Create a copy of FROM.  */
static deps_t
create_copy_of_deps_context (deps_t from)
{
  deps_t to = alloc_deps_context ();

  copy_deps_context (to, from);
  return to;
}

/* Clean up internal data of DC.  */
static void
clear_deps_context (deps_t dc)
{
  free_deps (dc);
}

/* Clear and free DC.  */
static void
delete_deps_context (deps_t dc)
{
  clear_deps_context (dc);
  free (dc);
}

/* Clear and init DC.  */
static void
reset_deps_context (deps_t dc)
{
  clear_deps_context (dc);
  init_deps (dc, false);
}

/* This structure describes the dependence analysis hooks for advancing
   dependence context.  */
static struct sched_deps_info_def advance_deps_context_sched_deps_info =
  {
    NULL,

    NULL, /* start_insn */
    NULL, /* finish_insn */
    NULL, /* start_lhs */
    NULL, /* finish_lhs */
    NULL, /* start_rhs */
    NULL, /* finish_rhs */
    haifa_note_reg_set,
    haifa_note_reg_clobber,
    haifa_note_reg_use,
    NULL, /* note_mem_dep */
    NULL, /* note_dep */

    0, 0, 0
  };

/* Process INSN and add its impact on DC.  */
void
advance_deps_context (deps_t dc, insn_t insn)
{
  sched_deps_info = &advance_deps_context_sched_deps_info;
  deps_analyze_insn (dc, insn);
}


/* Functions to work with DFA states.  */

/* Allocate store for a DFA state.  */
static state_t
state_alloc (void)
{
  return xmalloc (dfa_state_size);
}

/* Allocate and initialize DFA state.  */
static state_t
state_create (void)
{
  state_t state = state_alloc ();

  state_reset (state);
  advance_state (state);
  return state;
}

/* Free DFA state.  */
static void
state_free (state_t state)
{
  free (state);
}

/* Make a copy of FROM in TO.  */
static void
state_copy (state_t to, state_t from)
{
  memcpy (to, from, dfa_state_size);
}

/* Create a copy of FROM.  */
static state_t
state_create_copy (state_t from)
{
  state_t to = state_alloc ();

  state_copy (to, from);
  return to;
}


/* Functions to work with fences.  */

/* Clear the fence.  */
static void
fence_clear (fence_t f)
{
  state_t s = FENCE_STATE (f);
  deps_t dc = FENCE_DC (f);
  void *tc = FENCE_TC (f);

  ilist_clear (&FENCE_BNDS (f));

  gcc_assert ((s != NULL && dc != NULL && tc != NULL)
	      || (s == NULL && dc == NULL && tc == NULL));

  free (s);

  if (dc != NULL)
    delete_deps_context (dc);

  if (tc != NULL)
    delete_target_context (tc);
  vec_free (FENCE_EXECUTING_INSNS (f));
  free (FENCE_READY_TICKS (f));
  FENCE_READY_TICKS (f) = NULL;
}

/* Init a list of fences with successors of OLD_FENCE.  */
void
init_fences (insn_t old_fence)
{
  insn_t succ;
  succ_iterator si;
  bool first = true;
  int ready_ticks_size = get_max_uid () + 1;

  FOR_EACH_SUCC_1 (succ, si, old_fence,
                   SUCCS_NORMAL | SUCCS_SKIP_TO_LOOP_EXITS)
    {

      if (first)
        first = false;
      else
        gcc_assert (flag_sel_sched_pipelining_outer_loops);

      flist_add (&fences, succ,
		 state_create (),
		 create_deps_context () /* dc */,
		 create_target_context (true) /* tc */,
		 NULL_RTX /* last_scheduled_insn */,
                 NULL, /* executing_insns */
                 XCNEWVEC (int, ready_ticks_size), /* ready_ticks */
                 ready_ticks_size,
                 NULL_RTX /* sched_next */,
		 1 /* cycle */, 0 /* cycle_issued_insns */,
		 issue_rate, /* issue_more */
		 1 /* starts_cycle_p */, 0 /* after_stall_p */);
    }
}

/* Merges two fences (filling fields of fence F with resulting values) by
   following rules: 1) state, target context and last scheduled insn are
   propagated from fallthrough edge if it is available;
   2) deps context and cycle is propagated from more probable edge;
   3) all other fields are set to corresponding constant values.

   INSN, STATE, DC, TC, LAST_SCHEDULED_INSN, EXECUTING_INSNS,
   READY_TICKS, READY_TICKS_SIZE, SCHED_NEXT, CYCLE, ISSUE_MORE
   and AFTER_STALL_P are the corresponding fields of the second fence.  */
static void
merge_fences (fence_t f, insn_t insn,
	      state_t state, deps_t dc, void *tc,
              rtx last_scheduled_insn, vec<rtx, va_gc> *executing_insns,
              int *ready_ticks, int ready_ticks_size,
	      rtx sched_next, int cycle, int issue_more, bool after_stall_p)
{
  insn_t last_scheduled_insn_old = FENCE_LAST_SCHEDULED_INSN (f);

  gcc_assert (sel_bb_head_p (FENCE_INSN (f))
              && !sched_next && !FENCE_SCHED_NEXT (f));

  /* Check if we can decide which path fences came.
     If we can't (or don't want to) - reset all.  */
  if (last_scheduled_insn == NULL
      || last_scheduled_insn_old == NULL
      /* This is a case when INSN is reachable on several paths from
         one insn (this can happen when pipelining of outer loops is on and
         there are two edges: one going around of inner loop and the other -
         right through it; in such case just reset everything).  */
      || last_scheduled_insn == last_scheduled_insn_old)
    {
      state_reset (FENCE_STATE (f));
      state_free (state);

      reset_deps_context (FENCE_DC (f));
      delete_deps_context (dc);

      reset_target_context (FENCE_TC (f), true);
      delete_target_context (tc);

      if (cycle > FENCE_CYCLE (f))
        FENCE_CYCLE (f) = cycle;

      FENCE_LAST_SCHEDULED_INSN (f) = NULL;
      FENCE_ISSUE_MORE (f) = issue_rate;
      vec_free (executing_insns);
      free (ready_ticks);
      if (FENCE_EXECUTING_INSNS (f))
        FENCE_EXECUTING_INSNS (f)->block_remove (0,
					  FENCE_EXECUTING_INSNS (f)->length ());
      if (FENCE_READY_TICKS (f))
        memset (FENCE_READY_TICKS (f), 0, FENCE_READY_TICKS_SIZE (f));
    }
  else
    {
      edge edge_old = NULL, edge_new = NULL;
      edge candidate;
      succ_iterator si;
      insn_t succ;

      /* Find fallthrough edge.  */
      gcc_assert (BLOCK_FOR_INSN (insn)->prev_bb);
      candidate = find_fallthru_edge_from (BLOCK_FOR_INSN (insn)->prev_bb);

      if (!candidate
          || (candidate->src != BLOCK_FOR_INSN (last_scheduled_insn)
              && candidate->src != BLOCK_FOR_INSN (last_scheduled_insn_old)))
        {
          /* No fallthrough edge leading to basic block of INSN.  */
          state_reset (FENCE_STATE (f));
          state_free (state);

          reset_target_context (FENCE_TC (f), true);
          delete_target_context (tc);

          FENCE_LAST_SCHEDULED_INSN (f) = NULL;
	  FENCE_ISSUE_MORE (f) = issue_rate;
        }
      else
        if (candidate->src == BLOCK_FOR_INSN (last_scheduled_insn))
          {
            /* Would be weird if same insn is successor of several fallthrough
               edges.  */
            gcc_assert (BLOCK_FOR_INSN (insn)->prev_bb
                        != BLOCK_FOR_INSN (last_scheduled_insn_old));

            state_free (FENCE_STATE (f));
            FENCE_STATE (f) = state;

            delete_target_context (FENCE_TC (f));
            FENCE_TC (f) = tc;

            FENCE_LAST_SCHEDULED_INSN (f) = last_scheduled_insn;
	    FENCE_ISSUE_MORE (f) = issue_more;
          }
        else
          {
            /* Leave STATE, TC and LAST_SCHEDULED_INSN fields untouched.  */
            state_free (state);
            delete_target_context (tc);

            gcc_assert (BLOCK_FOR_INSN (insn)->prev_bb
                        != BLOCK_FOR_INSN (last_scheduled_insn));
          }

        /* Find edge of first predecessor (last_scheduled_insn_old->insn).  */
        FOR_EACH_SUCC_1 (succ, si, last_scheduled_insn_old,
                         SUCCS_NORMAL | SUCCS_SKIP_TO_LOOP_EXITS)
          {
            if (succ == insn)
              {
                /* No same successor allowed from several edges.  */
                gcc_assert (!edge_old);
                edge_old = si.e1;
              }
          }
        /* Find edge of second predecessor (last_scheduled_insn->insn).  */
        FOR_EACH_SUCC_1 (succ, si, last_scheduled_insn,
                         SUCCS_NORMAL | SUCCS_SKIP_TO_LOOP_EXITS)
          {
            if (succ == insn)
              {
                /* No same successor allowed from several edges.  */
                gcc_assert (!edge_new);
                edge_new = si.e1;
              }
          }

        /* Check if we can choose most probable predecessor.  */
        if (edge_old == NULL || edge_new == NULL)
          {
            reset_deps_context (FENCE_DC (f));
            delete_deps_context (dc);
            vec_free (executing_insns);
            free (ready_ticks);

            FENCE_CYCLE (f) = MAX (FENCE_CYCLE (f), cycle);
            if (FENCE_EXECUTING_INSNS (f))
              FENCE_EXECUTING_INSNS (f)->block_remove (0,
                                FENCE_EXECUTING_INSNS (f)->length ());
            if (FENCE_READY_TICKS (f))
              memset (FENCE_READY_TICKS (f), 0, FENCE_READY_TICKS_SIZE (f));
          }
        else
          if (edge_new->probability > edge_old->probability)
            {
              delete_deps_context (FENCE_DC (f));
              FENCE_DC (f) = dc;
              vec_free (FENCE_EXECUTING_INSNS (f));
              FENCE_EXECUTING_INSNS (f) = executing_insns;
              free (FENCE_READY_TICKS (f));
              FENCE_READY_TICKS (f) = ready_ticks;
              FENCE_READY_TICKS_SIZE (f) = ready_ticks_size;
              FENCE_CYCLE (f) = cycle;
            }
          else
            {
              /* Leave DC and CYCLE untouched.  */
              delete_deps_context (dc);
              vec_free (executing_insns);
              free (ready_ticks);
            }
    }

  /* Fill remaining invariant fields.  */
  if (after_stall_p)
    FENCE_AFTER_STALL_P (f) = 1;

  FENCE_ISSUED_INSNS (f) = 0;
  FENCE_STARTS_CYCLE_P (f) = 1;
  FENCE_SCHED_NEXT (f) = NULL;
}

/* Add a new fence to NEW_FENCES list, initializing it from all
   other parameters.  */
static void
add_to_fences (flist_tail_t new_fences, insn_t insn,
               state_t state, deps_t dc, void *tc, rtx last_scheduled_insn,
               vec<rtx, va_gc> *executing_insns, int *ready_ticks,
               int ready_ticks_size, rtx sched_next, int cycle,
               int cycle_issued_insns, int issue_rate,
	       bool starts_cycle_p, bool after_stall_p)
{
  fence_t f = flist_lookup (FLIST_TAIL_HEAD (new_fences), insn);

  if (! f)
    {
      flist_add (FLIST_TAIL_TAILP (new_fences), insn, state, dc, tc,
		 last_scheduled_insn, executing_insns, ready_ticks,
                 ready_ticks_size, sched_next, cycle, cycle_issued_insns,
		 issue_rate, starts_cycle_p, after_stall_p);

      FLIST_TAIL_TAILP (new_fences)
	= &FLIST_NEXT (*FLIST_TAIL_TAILP (new_fences));
    }
  else
    {
      merge_fences (f, insn, state, dc, tc, last_scheduled_insn,
                    executing_insns, ready_ticks, ready_ticks_size,
                    sched_next, cycle, issue_rate, after_stall_p);
    }
}

/* Move the first fence in the OLD_FENCES list to NEW_FENCES.  */
void
move_fence_to_fences (flist_t old_fences, flist_tail_t new_fences)
{
  fence_t f, old;
  flist_t *tailp = FLIST_TAIL_TAILP (new_fences);

  old = FLIST_FENCE (old_fences);
  f = flist_lookup (FLIST_TAIL_HEAD (new_fences),
                    FENCE_INSN (FLIST_FENCE (old_fences)));
  if (f)
    {
      merge_fences (f, old->insn, old->state, old->dc, old->tc,
                    old->last_scheduled_insn, old->executing_insns,
                    old->ready_ticks, old->ready_ticks_size,
                    old->sched_next, old->cycle, old->issue_more,
                    old->after_stall_p);
    }
  else
    {
      _list_add (tailp);
      FLIST_TAIL_TAILP (new_fences) = &FLIST_NEXT (*tailp);
      *FLIST_FENCE (*tailp) = *old;
      init_fence_for_scheduling (FLIST_FENCE (*tailp));
    }
  FENCE_INSN (old) = NULL;
}

/* Add a new fence to NEW_FENCES list and initialize most of its data
   as a clean one.  */
void
add_clean_fence_to_fences (flist_tail_t new_fences, insn_t succ, fence_t fence)
{
  int ready_ticks_size = get_max_uid () + 1;

  add_to_fences (new_fences,
                 succ, state_create (), create_deps_context (),
                 create_target_context (true),
                 NULL_RTX, NULL,
                 XCNEWVEC (int, ready_ticks_size), ready_ticks_size,
                 NULL_RTX, FENCE_CYCLE (fence) + 1,
                 0, issue_rate, 1, FENCE_AFTER_STALL_P (fence));
}

/* Add a new fence to NEW_FENCES list and initialize all of its data
   from FENCE and SUCC.  */
void
add_dirty_fence_to_fences (flist_tail_t new_fences, insn_t succ, fence_t fence)
{
  int * new_ready_ticks
    = XNEWVEC (int, FENCE_READY_TICKS_SIZE (fence));

  memcpy (new_ready_ticks, FENCE_READY_TICKS (fence),
          FENCE_READY_TICKS_SIZE (fence) * sizeof (int));
  add_to_fences (new_fences,
                 succ, state_create_copy (FENCE_STATE (fence)),
                 create_copy_of_deps_context (FENCE_DC (fence)),
                 create_copy_of_target_context (FENCE_TC (fence)),
                 FENCE_LAST_SCHEDULED_INSN (fence),
		 vec_safe_copy (FENCE_EXECUTING_INSNS (fence)),
                 new_ready_ticks,
                 FENCE_READY_TICKS_SIZE (fence),
                 FENCE_SCHED_NEXT (fence),
                 FENCE_CYCLE (fence),
                 FENCE_ISSUED_INSNS (fence),
		 FENCE_ISSUE_MORE (fence),
                 FENCE_STARTS_CYCLE_P (fence),
                 FENCE_AFTER_STALL_P (fence));
}


/* Functions to work with regset and nop pools.  */

/* Returns the new regset from pool.  It might have some of the bits set
   from the previous usage.  */
regset
get_regset_from_pool (void)
{
  regset rs;

  if (regset_pool.n != 0)
    rs = regset_pool.v[--regset_pool.n];
  else
    /* We need to create the regset.  */
    {
      rs = ALLOC_REG_SET (&reg_obstack);

      if (regset_pool.nn == regset_pool.ss)
	regset_pool.vv = XRESIZEVEC (regset, regset_pool.vv,
                                     (regset_pool.ss = 2 * regset_pool.ss + 1));
      regset_pool.vv[regset_pool.nn++] = rs;
    }

  regset_pool.diff++;

  return rs;
}

/* Same as above, but returns the empty regset.  */
regset
get_clear_regset_from_pool (void)
{
  regset rs = get_regset_from_pool ();

  CLEAR_REG_SET (rs);
  return rs;
}

/* Return regset RS to the pool for future use.  */
void
return_regset_to_pool (regset rs)
{
  gcc_assert (rs);
  regset_pool.diff--;

  if (regset_pool.n == regset_pool.s)
    regset_pool.v = XRESIZEVEC (regset, regset_pool.v,
                                (regset_pool.s = 2 * regset_pool.s + 1));
  regset_pool.v[regset_pool.n++] = rs;
}

#ifdef ENABLE_CHECKING
/* This is used as a qsort callback for sorting regset pool stacks.
   X and XX are addresses of two regsets.  They are never equal.  */
static int
cmp_v_in_regset_pool (const void *x, const void *xx)
{
  uintptr_t r1 = (uintptr_t) *((const regset *) x);
  uintptr_t r2 = (uintptr_t) *((const regset *) xx);
  if (r1 > r2)
    return 1;
  else if (r1 < r2)
    return -1;
  gcc_unreachable ();
}
#endif

/*  Free the regset pool possibly checking for memory leaks.  */
void
free_regset_pool (void)
{
#ifdef ENABLE_CHECKING
  {
    regset *v = regset_pool.v;
    int i = 0;
    int n = regset_pool.n;

    regset *vv = regset_pool.vv;
    int ii = 0;
    int nn = regset_pool.nn;

    int diff = 0;

    gcc_assert (n <= nn);

    /* Sort both vectors so it will be possible to compare them.  */
    qsort (v, n, sizeof (*v), cmp_v_in_regset_pool);
    qsort (vv, nn, sizeof (*vv), cmp_v_in_regset_pool);

    while (ii < nn)
      {
        if (v[i] == vv[ii])
          i++;
        else
          /* VV[II] was lost.  */
          diff++;

        ii++;
      }

    gcc_assert (diff == regset_pool.diff);
  }
#endif

  /* If not true - we have a memory leak.  */
  gcc_assert (regset_pool.diff == 0);

  while (regset_pool.n)
    {
      --regset_pool.n;
      FREE_REG_SET (regset_pool.v[regset_pool.n]);
    }

  free (regset_pool.v);
  regset_pool.v = NULL;
  regset_pool.s = 0;

  free (regset_pool.vv);
  regset_pool.vv = NULL;
  regset_pool.nn = 0;
  regset_pool.ss = 0;

  regset_pool.diff = 0;
}


/* Functions to work with nop pools.  NOP insns are used as temporary
   placeholders of the insns being scheduled to allow correct update of
   the data sets.  When update is finished, NOPs are deleted.  */

/* A vinsn that is used to represent a nop.  This vinsn is shared among all
   nops sel-sched generates.  */
static vinsn_t nop_vinsn = NULL;

/* Emit a nop before INSN, taking it from pool.  */
insn_t
get_nop_from_pool (insn_t insn)
{
  insn_t nop;
  bool old_p = nop_pool.n != 0;
  int flags;

  if (old_p)
    nop = nop_pool.v[--nop_pool.n];
  else
    nop = nop_pattern;

  nop = emit_insn_before (nop, insn);

  if (old_p)
    flags = INSN_INIT_TODO_SSID;
  else
    flags = INSN_INIT_TODO_LUID | INSN_INIT_TODO_SSID;

  set_insn_init (INSN_EXPR (insn), nop_vinsn, INSN_SEQNO (insn));
  sel_init_new_insn (nop, flags);

  return nop;
}

/* Remove NOP from the instruction stream and return it to the pool.  */
void
return_nop_to_pool (insn_t nop, bool full_tidying)
{
  gcc_assert (INSN_IN_STREAM_P (nop));
  sel_remove_insn (nop, false, full_tidying);

  /* We'll recycle this nop.  */
  INSN_DELETED_P (nop) = 0;

  if (nop_pool.n == nop_pool.s)
    nop_pool.v = XRESIZEVEC (rtx, nop_pool.v,
                             (nop_pool.s = 2 * nop_pool.s + 1));
  nop_pool.v[nop_pool.n++] = nop;
}

/* Free the nop pool.  */
void
free_nop_pool (void)
{
  nop_pool.n = 0;
  nop_pool.s = 0;
  free (nop_pool.v);
  nop_pool.v = NULL;
}


/* Skip unspec to support ia64 speculation. Called from rtx_equal_p_cb.
   The callback is given two rtxes XX and YY and writes the new rtxes
   to NX and NY in case some needs to be skipped.  */
static int
skip_unspecs_callback (const_rtx *xx, const_rtx *yy, rtx *nx, rtx* ny)
{
  const_rtx x = *xx;
  const_rtx y = *yy;

  if (GET_CODE (x) == UNSPEC
      && (targetm.sched.skip_rtx_p == NULL
          || targetm.sched.skip_rtx_p (x)))
    {
      *nx = XVECEXP (x, 0, 0);
      *ny = CONST_CAST_RTX (y);
      return 1;
    }

  if (GET_CODE (y) == UNSPEC
      && (targetm.sched.skip_rtx_p == NULL
          || targetm.sched.skip_rtx_p (y)))
    {
      *nx = CONST_CAST_RTX (x);
      *ny = XVECEXP (y, 0, 0);
      return 1;
    }

  return 0;
}

/* Callback, called from hash_rtx_cb.  Helps to hash UNSPEC rtx X in a correct way
   to support ia64 speculation.  When changes are needed, new rtx X and new mode
   NMODE are written, and the callback returns true.  */
static int
hash_with_unspec_callback (const_rtx x, enum machine_mode mode ATTRIBUTE_UNUSED,
                           rtx *nx, enum machine_mode* nmode)
{
  if (GET_CODE (x) == UNSPEC
      && targetm.sched.skip_rtx_p
      && targetm.sched.skip_rtx_p (x))
    {
      *nx = XVECEXP (x, 0 ,0);
      *nmode = VOIDmode;
      return 1;
    }

  return 0;
}

/* Returns LHS and RHS are ok to be scheduled separately.  */
static bool
lhs_and_rhs_separable_p (rtx lhs, rtx rhs)
{
  if (lhs == NULL || rhs == NULL)
    return false;

  /* Do not schedule CONST, CONST_INT and CONST_DOUBLE etc as rhs: no point
     to use reg, if const can be used.  Moreover, scheduling const as rhs may
     lead to mode mismatch cause consts don't have modes but they could be
     merged from branches where the same const used in different modes.  */
  if (CONSTANT_P (rhs))
    return false;

  /* ??? Do not rename predicate registers to avoid ICEs in bundling.  */
  if (COMPARISON_P (rhs))
      return false;

  /* Do not allow single REG to be an rhs.  */
  if (REG_P (rhs))
    return false;

  /* See comment at find_used_regs_1 (*1) for explanation of this
     restriction.  */
  /* FIXME: remove this later.  */
  if (MEM_P (lhs))
    return false;

  /* This will filter all tricky things like ZERO_EXTRACT etc.
     For now we don't handle it.  */
  if (!REG_P (lhs) && !MEM_P (lhs))
    return false;

  return true;
}

/* Initialize vinsn VI for INSN.  Only for use from vinsn_create ().  When
   FORCE_UNIQUE_P is true, the resulting vinsn will not be clonable.  This is
   used e.g. for insns from recovery blocks.  */
static void
vinsn_init (vinsn_t vi, insn_t insn, bool force_unique_p)
{
  hash_rtx_callback_function hrcf;
  int insn_class;

  VINSN_INSN_RTX (vi) = insn;
  VINSN_COUNT (vi) = 0;
  vi->cost = -1;

  if (INSN_NOP_P (insn))
    return;

  if (DF_INSN_UID_SAFE_GET (INSN_UID (insn)) != NULL)
    init_id_from_df (VINSN_ID (vi), insn, force_unique_p);
  else
    deps_init_id (VINSN_ID (vi), insn, force_unique_p);

  /* Hash vinsn depending on whether it is separable or not.  */
  hrcf = targetm.sched.skip_rtx_p ? hash_with_unspec_callback : NULL;
  if (VINSN_SEPARABLE_P (vi))
    {
      rtx rhs = VINSN_RHS (vi);

      VINSN_HASH (vi) = hash_rtx_cb (rhs, GET_MODE (rhs),
                                     NULL, NULL, false, hrcf);
      VINSN_HASH_RTX (vi) = hash_rtx_cb (VINSN_PATTERN (vi),
                                         VOIDmode, NULL, NULL,
                                         false, hrcf);
    }
  else
    {
      VINSN_HASH (vi) = hash_rtx_cb (VINSN_PATTERN (vi), VOIDmode,
                                     NULL, NULL, false, hrcf);
      VINSN_HASH_RTX (vi) = VINSN_HASH (vi);
    }

  insn_class = haifa_classify_insn (insn);
  if (insn_class >= 2
      && (!targetm.sched.get_insn_spec_ds
          || ((targetm.sched.get_insn_spec_ds (insn) & BEGIN_CONTROL)
              == 0)))
    VINSN_MAY_TRAP_P (vi) = true;
  else
    VINSN_MAY_TRAP_P (vi) = false;
}

/* Indicate that VI has become the part of an rtx object.  */
void
vinsn_attach (vinsn_t vi)
{
  /* Assert that VI is not pending for deletion.  */
  gcc_assert (VINSN_INSN_RTX (vi));

  VINSN_COUNT (vi)++;
}

/* Create and init VI from the INSN.  Use UNIQUE_P for determining the correct
   VINSN_TYPE (VI).  */
static vinsn_t
vinsn_create (insn_t insn, bool force_unique_p)
{
  vinsn_t vi = XCNEW (struct vinsn_def);

  vinsn_init (vi, insn, force_unique_p);
  return vi;
}

/* Return a copy of VI.  When REATTACH_P is true, detach VI and attach
   the copy.  */
vinsn_t
vinsn_copy (vinsn_t vi, bool reattach_p)
{
  rtx copy;
  bool unique = VINSN_UNIQUE_P (vi);
  vinsn_t new_vi;

  copy = create_copy_of_insn_rtx (VINSN_INSN_RTX (vi));
  new_vi = create_vinsn_from_insn_rtx (copy, unique);
  if (reattach_p)
    {
      vinsn_detach (vi);
      vinsn_attach (new_vi);
    }

  return new_vi;
}

/* Delete the VI vinsn and free its data.  */
static void
vinsn_delete (vinsn_t vi)
{
  gcc_assert (VINSN_COUNT (vi) == 0);

  if (!INSN_NOP_P (VINSN_INSN_RTX (vi)))
    {
      return_regset_to_pool (VINSN_REG_SETS (vi));
      return_regset_to_pool (VINSN_REG_USES (vi));
      return_regset_to_pool (VINSN_REG_CLOBBERS (vi));
    }

  free (vi);
}

/* Indicate that VI is no longer a part of some rtx object.
   Remove VI if it is no longer needed.  */
void
vinsn_detach (vinsn_t vi)
{
  gcc_assert (VINSN_COUNT (vi) > 0);

  if (--VINSN_COUNT (vi) == 0)
    vinsn_delete (vi);
}

/* Returns TRUE if VI is a branch.  */
bool
vinsn_cond_branch_p (vinsn_t vi)
{
  insn_t insn;

  if (!VINSN_UNIQUE_P (vi))
    return false;

  insn = VINSN_INSN_RTX (vi);
  if (BB_END (BLOCK_FOR_INSN (insn)) != insn)
    return false;

  return control_flow_insn_p (insn);
}

/* Return latency of INSN.  */
static int
sel_insn_rtx_cost (rtx insn)
{
  int cost;

  /* A USE insn, or something else we don't need to
     understand.  We can't pass these directly to
     result_ready_cost or insn_default_latency because it will
     trigger a fatal error for unrecognizable insns.  */
  if (recog_memoized (insn) < 0)
    cost = 0;
  else
    {
      cost = insn_default_latency (insn);

      if (cost < 0)
	cost = 0;
    }

  return cost;
}

/* Return the cost of the VI.
   !!! FIXME: Unify with haifa-sched.c: insn_cost ().  */
int
sel_vinsn_cost (vinsn_t vi)
{
  int cost = vi->cost;

  if (cost < 0)
    {
      cost = sel_insn_rtx_cost (VINSN_INSN_RTX (vi));
      vi->cost = cost;
    }

  return cost;
}


/* Functions for insn emitting.  */

/* Emit new insn after AFTER based on PATTERN and initialize its data from
   EXPR and SEQNO.  */
insn_t
sel_gen_insn_from_rtx_after (rtx pattern, expr_t expr, int seqno, insn_t after)
{
  insn_t new_insn;

  gcc_assert (EXPR_TARGET_AVAILABLE (expr) == true);

  new_insn = emit_insn_after (pattern, after);
  set_insn_init (expr, NULL, seqno);
  sel_init_new_insn (new_insn, INSN_INIT_TODO_LUID | INSN_INIT_TODO_SSID);

  return new_insn;
}

/* Force newly generated vinsns to be unique.  */
static bool init_insn_force_unique_p = false;

/* Emit new speculation recovery insn after AFTER based on PATTERN and
   initialize its data from EXPR and SEQNO.  */
insn_t
sel_gen_recovery_insn_from_rtx_after (rtx pattern, expr_t expr, int seqno,
				      insn_t after)
{
  insn_t insn;

  gcc_assert (!init_insn_force_unique_p);

  init_insn_force_unique_p = true;
  insn = sel_gen_insn_from_rtx_after (pattern, expr, seqno, after);
  CANT_MOVE (insn) = 1;
  init_insn_force_unique_p = false;

  return insn;
}

/* Emit new insn after AFTER based on EXPR and SEQNO.  If VINSN is not NULL,
   take it as a new vinsn instead of EXPR's vinsn.
   We simplify insns later, after scheduling region in
   simplify_changed_insns.  */
insn_t
sel_gen_insn_from_expr_after (expr_t expr, vinsn_t vinsn, int seqno,
                              insn_t after)
{
  expr_t emit_expr;
  insn_t insn;
  int flags;

  emit_expr = set_insn_init (expr, vinsn ? vinsn : EXPR_VINSN (expr),
                             seqno);
  insn = EXPR_INSN_RTX (emit_expr);

  /* The insn may come from the transformation cache, which may hold already
     deleted insns, so mark it as not deleted.  */
  INSN_DELETED_P (insn) = 0;

  add_insn_after (insn, after, BLOCK_FOR_INSN (insn));

  flags = INSN_INIT_TODO_SSID;
  if (INSN_LUID (insn) == 0)
    flags |= INSN_INIT_TODO_LUID;
  sel_init_new_insn (insn, flags);

  return insn;
}

/* Move insn from EXPR after AFTER.  */
insn_t
sel_move_insn (expr_t expr, int seqno, insn_t after)
{
  insn_t insn = EXPR_INSN_RTX (expr);
  basic_block bb = BLOCK_FOR_INSN (after);
  insn_t next = NEXT_INSN (after);

  /* Assert that in move_op we disconnected this insn properly.  */
  gcc_assert (EXPR_VINSN (INSN_EXPR (insn)) != NULL);
  PREV_INSN (insn) = after;
  NEXT_INSN (insn) = next;

  NEXT_INSN (after) = insn;
  PREV_INSN (next) = insn;

  /* Update links from insn to bb and vice versa.  */
  df_insn_change_bb (insn, bb);
  if (BB_END (bb) == after)
    BB_END (bb) = insn;

  prepare_insn_expr (insn, seqno);
  return insn;
}


/* Functions to work with right-hand sides.  */

/* Search for a hash value determined by UID/NEW_VINSN in a sorted vector
   VECT and return true when found.  Use NEW_VINSN for comparison only when
   COMPARE_VINSNS is true.  Write to INDP the index on which
   the search has stopped, such that inserting the new element at INDP will
   retain VECT's sort order.  */
static bool
find_in_history_vect_1 (vec<expr_history_def> vect,
                        unsigned uid, vinsn_t new_vinsn,
                        bool compare_vinsns, int *indp)
{
  expr_history_def *arr;
  int i, j, len = vect.length ();

  if (len == 0)
    {
      *indp = 0;
      return false;
    }

  arr = vect.address ();
  i = 0, j = len - 1;

  while (i <= j)
    {
      unsigned auid = arr[i].uid;
      vinsn_t avinsn = arr[i].new_expr_vinsn;

      if (auid == uid
          /* When undoing transformation on a bookkeeping copy, the new vinsn
             may not be exactly equal to the one that is saved in the vector.
             This is because the insn whose copy we're checking was possibly
             substituted itself.  */
          && (! compare_vinsns
              || vinsn_equal_p (avinsn, new_vinsn)))
        {
          *indp = i;
          return true;
        }
      else if (auid > uid)
        break;
      i++;
    }

  *indp = i;
  return false;
}

/* Search for a uid of INSN and NEW_VINSN in a sorted vector VECT.  Return
   the position found or -1, if no such value is in vector.
   Search also for UIDs of insn's originators, if ORIGINATORS_P is true.  */
int
find_in_history_vect (vec<expr_history_def> vect, rtx insn,
                      vinsn_t new_vinsn, bool originators_p)
{
  int ind;

  if (find_in_history_vect_1 (vect, INSN_UID (insn), new_vinsn,
                              false, &ind))
    return ind;

  if (INSN_ORIGINATORS (insn) && originators_p)
    {
      unsigned uid;
      bitmap_iterator bi;

      EXECUTE_IF_SET_IN_BITMAP (INSN_ORIGINATORS (insn), 0, uid, bi)
        if (find_in_history_vect_1 (vect, uid, new_vinsn, false, &ind))
          return ind;
    }

  return -1;
}

/* Insert new element in a sorted history vector pointed to by PVECT,
   if it is not there already.  The element is searched using
   UID/NEW_EXPR_VINSN pair.  TYPE, OLD_EXPR_VINSN and SPEC_DS save
   the history of a transformation.  */
void
insert_in_history_vect (vec<expr_history_def> *pvect,
                        unsigned uid, enum local_trans_type type,
                        vinsn_t old_expr_vinsn, vinsn_t new_expr_vinsn,
                        ds_t spec_ds)
{
  vec<expr_history_def> vect = *pvect;
  expr_history_def temp;
  bool res;
  int ind;

  res = find_in_history_vect_1 (vect, uid, new_expr_vinsn, true, &ind);

  if (res)
    {
      expr_history_def *phist = &vect[ind];

      /* It is possible that speculation types of expressions that were
         propagated through different paths will be different here.  In this
         case, merge the status to get the correct check later.  */
      if (phist->spec_ds != spec_ds)
        phist->spec_ds = ds_max_merge (phist->spec_ds, spec_ds);
      return;
    }

  temp.uid = uid;
  temp.old_expr_vinsn = old_expr_vinsn;
  temp.new_expr_vinsn = new_expr_vinsn;
  temp.spec_ds = spec_ds;
  temp.type = type;

  vinsn_attach (old_expr_vinsn);
  vinsn_attach (new_expr_vinsn);
  vect.safe_insert (ind, temp);
  *pvect = vect;
}

/* Free history vector PVECT.  */
static void
free_history_vect (vec<expr_history_def> &pvect)
{
  unsigned i;
  expr_history_def *phist;

  if (! pvect.exists ())
    return;

  for (i = 0; pvect.iterate (i, &phist); i++)
    {
      vinsn_detach (phist->old_expr_vinsn);
      vinsn_detach (phist->new_expr_vinsn);
    }

  pvect.release ();
}

/* Merge vector FROM to PVECT.  */
static void
merge_history_vect (vec<expr_history_def> *pvect,
		    vec<expr_history_def> from)
{
  expr_history_def *phist;
  int i;

  /* We keep this vector sorted.  */
  for (i = 0; from.iterate (i, &phist); i++)
    insert_in_history_vect (pvect, phist->uid, phist->type,
                            phist->old_expr_vinsn, phist->new_expr_vinsn,
                            phist->spec_ds);
}

/* Compare two vinsns as rhses if possible and as vinsns otherwise.  */
bool
vinsn_equal_p (vinsn_t x, vinsn_t y)
{
  rtx_equal_p_callback_function repcf;

  if (x == y)
    return true;

  if (VINSN_TYPE (x) != VINSN_TYPE (y))
    return false;

  if (VINSN_HASH (x) != VINSN_HASH (y))
    return false;

  repcf = targetm.sched.skip_rtx_p ? skip_unspecs_callback : NULL;
  if (VINSN_SEPARABLE_P (x))
    {
      /* Compare RHSes of VINSNs.  */
      gcc_assert (VINSN_RHS (x));
      gcc_assert (VINSN_RHS (y));

      return rtx_equal_p_cb (VINSN_RHS (x), VINSN_RHS (y), repcf);
    }

  return rtx_equal_p_cb (VINSN_PATTERN (x), VINSN_PATTERN (y), repcf);
}


/* Functions for working with expressions.  */

/* Initialize EXPR.  */
static void
init_expr (expr_t expr, vinsn_t vi, int spec, int use, int priority,
	   int sched_times, int orig_bb_index, ds_t spec_done_ds,
	   ds_t spec_to_check_ds, int orig_sched_cycle,
	   vec<expr_history_def> history,
	   signed char target_available,
           bool was_substituted, bool was_renamed, bool needs_spec_check_p,
           bool cant_move)
{
  vinsn_attach (vi);

  EXPR_VINSN (expr) = vi;
  EXPR_SPEC (expr) = spec;
  EXPR_USEFULNESS (expr) = use;
  EXPR_PRIORITY (expr) = priority;
  EXPR_PRIORITY_ADJ (expr) = 0;
  EXPR_SCHED_TIMES (expr) = sched_times;
  EXPR_ORIG_BB_INDEX (expr) = orig_bb_index;
  EXPR_ORIG_SCHED_CYCLE (expr) = orig_sched_cycle;
  EXPR_SPEC_DONE_DS (expr) = spec_done_ds;
  EXPR_SPEC_TO_CHECK_DS (expr) = spec_to_check_ds;

  if (history.exists ())
    EXPR_HISTORY_OF_CHANGES (expr) = history;
  else
    EXPR_HISTORY_OF_CHANGES (expr).create (0);

  EXPR_TARGET_AVAILABLE (expr) = target_available;
  EXPR_WAS_SUBSTITUTED (expr) = was_substituted;
  EXPR_WAS_RENAMED (expr) = was_renamed;
  EXPR_NEEDS_SPEC_CHECK_P (expr) = needs_spec_check_p;
  EXPR_CANT_MOVE (expr) = cant_move;
}

/* Make a copy of the expr FROM into the expr TO.  */
void
copy_expr (expr_t to, expr_t from)
{
  vec<expr_history_def> temp = vNULL;

  if (EXPR_HISTORY_OF_CHANGES (from).exists ())
    {
      unsigned i;
      expr_history_def *phist;

      temp = EXPR_HISTORY_OF_CHANGES (from).copy ();
      for (i = 0;
           temp.iterate (i, &phist);
           i++)
        {
          vinsn_attach (phist->old_expr_vinsn);
          vinsn_attach (phist->new_expr_vinsn);
        }
    }

  init_expr (to, EXPR_VINSN (from), EXPR_SPEC (from),
             EXPR_USEFULNESS (from), EXPR_PRIORITY (from),
	     EXPR_SCHED_TIMES (from), EXPR_ORIG_BB_INDEX (from),
	     EXPR_SPEC_DONE_DS (from), EXPR_SPEC_TO_CHECK_DS (from),
	     EXPR_ORIG_SCHED_CYCLE (from), temp,
             EXPR_TARGET_AVAILABLE (from), EXPR_WAS_SUBSTITUTED (from),
             EXPR_WAS_RENAMED (from), EXPR_NEEDS_SPEC_CHECK_P (from),
             EXPR_CANT_MOVE (from));
}

/* Same, but the final expr will not ever be in av sets, so don't copy
   "uninteresting" data such as bitmap cache.  */
void
copy_expr_onside (expr_t to, expr_t from)
{
  init_expr (to, EXPR_VINSN (from), EXPR_SPEC (from), EXPR_USEFULNESS (from),
	     EXPR_PRIORITY (from), EXPR_SCHED_TIMES (from), 0,
	     EXPR_SPEC_DONE_DS (from), EXPR_SPEC_TO_CHECK_DS (from), 0,
	     vNULL,
	     EXPR_TARGET_AVAILABLE (from), EXPR_WAS_SUBSTITUTED (from),
	     EXPR_WAS_RENAMED (from), EXPR_NEEDS_SPEC_CHECK_P (from),
             EXPR_CANT_MOVE (from));
}

/* Prepare the expr of INSN for scheduling.  Used when moving insn and when
   initializing new insns.  */
static void
prepare_insn_expr (insn_t insn, int seqno)
{
  expr_t expr = INSN_EXPR (insn);
  ds_t ds;

  INSN_SEQNO (insn) = seqno;
  EXPR_ORIG_BB_INDEX (expr) = BLOCK_NUM (insn);
  EXPR_SPEC (expr) = 0;
  EXPR_ORIG_SCHED_CYCLE (expr) = 0;
  EXPR_WAS_SUBSTITUTED (expr) = 0;
  EXPR_WAS_RENAMED (expr) = 0;
  EXPR_TARGET_AVAILABLE (expr) = 1;
  INSN_LIVE_VALID_P (insn) = false;

  /* ??? If this expression is speculative, make its dependence
     as weak as possible.  We can filter this expression later
     in process_spec_exprs, because we do not distinguish
     between the status we got during compute_av_set and the
     existing status.  To be fixed.  */
  ds = EXPR_SPEC_DONE_DS (expr);
  if (ds)
    EXPR_SPEC_DONE_DS (expr) = ds_get_max_dep_weak (ds);

  free_history_vect (EXPR_HISTORY_OF_CHANGES (expr));
}

/* Update target_available bits when merging exprs TO and FROM.  SPLIT_POINT
   is non-null when expressions are merged from different successors at
   a split point.  */
static void
update_target_availability (expr_t to, expr_t from, insn_t split_point)
{
  if (EXPR_TARGET_AVAILABLE (to) < 0
      || EXPR_TARGET_AVAILABLE (from) < 0)
    EXPR_TARGET_AVAILABLE (to) = -1;
  else
    {
      /* We try to detect the case when one of the expressions
         can only be reached through another one.  In this case,
         we can do better.  */
      if (split_point == NULL)
        {
          int toind, fromind;

          toind = EXPR_ORIG_BB_INDEX (to);
          fromind = EXPR_ORIG_BB_INDEX (from);

          if (toind && toind == fromind)
            /* Do nothing -- everything is done in
               merge_with_other_exprs.  */
            ;
          else
            EXPR_TARGET_AVAILABLE (to) = -1;
        }
      else if (EXPR_TARGET_AVAILABLE (from) == 0
	       && EXPR_LHS (from)
	       && REG_P (EXPR_LHS (from))
	       && REGNO (EXPR_LHS (to)) != REGNO (EXPR_LHS (from)))
	EXPR_TARGET_AVAILABLE (to) = -1;
      else
        EXPR_TARGET_AVAILABLE (to) &= EXPR_TARGET_AVAILABLE (from);
    }
}

/* Update speculation bits when merging exprs TO and FROM.  SPLIT_POINT
   is non-null when expressions are merged from different successors at
   a split point.  */
static void
update_speculative_bits (expr_t to, expr_t from, insn_t split_point)
{
  ds_t old_to_ds, old_from_ds;

  old_to_ds = EXPR_SPEC_DONE_DS (to);
  old_from_ds = EXPR_SPEC_DONE_DS (from);

  EXPR_SPEC_DONE_DS (to) = ds_max_merge (old_to_ds, old_from_ds);
  EXPR_SPEC_TO_CHECK_DS (to) |= EXPR_SPEC_TO_CHECK_DS (from);
  EXPR_NEEDS_SPEC_CHECK_P (to) |= EXPR_NEEDS_SPEC_CHECK_P (from);

  /* When merging e.g. control & data speculative exprs, or a control
     speculative with a control&data speculative one, we really have
     to change vinsn too.  Also, when speculative status is changed,
     we also need to record this as a transformation in expr's history.  */
  if ((old_to_ds & SPECULATIVE) || (old_from_ds & SPECULATIVE))
    {
      old_to_ds = ds_get_speculation_types (old_to_ds);
      old_from_ds = ds_get_speculation_types (old_from_ds);

      if (old_to_ds != old_from_ds)
        {
          ds_t record_ds;

          /* When both expressions are speculative, we need to change
             the vinsn first.  */
          if ((old_to_ds & SPECULATIVE) && (old_from_ds & SPECULATIVE))
            {
              int res;

              res = speculate_expr (to, EXPR_SPEC_DONE_DS (to));
              gcc_assert (res >= 0);
            }

          if (split_point != NULL)
            {
              /* Record the change with proper status.  */
              record_ds = EXPR_SPEC_DONE_DS (to) & SPECULATIVE;
              record_ds &= ~(old_to_ds & SPECULATIVE);
              record_ds &= ~(old_from_ds & SPECULATIVE);

              insert_in_history_vect (&EXPR_HISTORY_OF_CHANGES (to),
                                      INSN_UID (split_point), TRANS_SPECULATION,
                                      EXPR_VINSN (from), EXPR_VINSN (to),
                                      record_ds);
            }
        }
    }
}


/* Merge bits of FROM expr to TO expr.  When SPLIT_POINT is not NULL,
   this is done along different paths.  */
void
merge_expr_data (expr_t to, expr_t from, insn_t split_point)
{
  /* Choose the maximum of the specs of merged exprs.  This is required
     for correctness of bookkeeping.  */
  if (EXPR_SPEC (to) < EXPR_SPEC (from))
    EXPR_SPEC (to) = EXPR_SPEC (from);

  if (split_point)
    EXPR_USEFULNESS (to) += EXPR_USEFULNESS (from);
  else
    EXPR_USEFULNESS (to) = MAX (EXPR_USEFULNESS (to),
                                EXPR_USEFULNESS (from));

  if (EXPR_PRIORITY (to) < EXPR_PRIORITY (from))
    EXPR_PRIORITY (to) = EXPR_PRIORITY (from);

  if (EXPR_SCHED_TIMES (to) > EXPR_SCHED_TIMES (from))
    EXPR_SCHED_TIMES (to) = EXPR_SCHED_TIMES (from);

  if (EXPR_ORIG_BB_INDEX (to) != EXPR_ORIG_BB_INDEX (from))
    EXPR_ORIG_BB_INDEX (to) = 0;

  EXPR_ORIG_SCHED_CYCLE (to) = MIN (EXPR_ORIG_SCHED_CYCLE (to),
                                    EXPR_ORIG_SCHED_CYCLE (from));

  EXPR_WAS_SUBSTITUTED (to) |= EXPR_WAS_SUBSTITUTED (from);
  EXPR_WAS_RENAMED (to) |= EXPR_WAS_RENAMED (from);
  EXPR_CANT_MOVE (to) |= EXPR_CANT_MOVE (from);

  merge_history_vect (&EXPR_HISTORY_OF_CHANGES (to),
		      EXPR_HISTORY_OF_CHANGES (from));
  update_target_availability (to, from, split_point);
  update_speculative_bits (to, from, split_point);
}

/* Merge bits of FROM expr to TO expr.  Vinsns in the exprs should be equal
   in terms of vinsn_equal_p.  SPLIT_POINT is non-null when expressions
   are merged from different successors at a split point.  */
void
merge_expr (expr_t to, expr_t from, insn_t split_point)
{
  vinsn_t to_vi = EXPR_VINSN (to);
  vinsn_t from_vi = EXPR_VINSN (from);

  gcc_assert (vinsn_equal_p (to_vi, from_vi));

  /* Make sure that speculative pattern is propagated into exprs that
     have non-speculative one.  This will provide us with consistent
     speculative bits and speculative patterns inside expr.  */
  if ((EXPR_SPEC_DONE_DS (from) != 0
       && EXPR_SPEC_DONE_DS (to) == 0)
      /* Do likewise for volatile insns, so that we always retain
	 the may_trap_p bit on the resulting expression.  */
      || (VINSN_MAY_TRAP_P (EXPR_VINSN (from))
	  && !VINSN_MAY_TRAP_P (EXPR_VINSN (to))))
    change_vinsn_in_expr (to, EXPR_VINSN (from));

  merge_expr_data (to, from, split_point);
  gcc_assert (EXPR_USEFULNESS (to) <= REG_BR_PROB_BASE);
}

/* Clear the information of this EXPR.  */
void
clear_expr (expr_t expr)
{

  vinsn_detach (EXPR_VINSN (expr));
  EXPR_VINSN (expr) = NULL;

  free_history_vect (EXPR_HISTORY_OF_CHANGES (expr));
}

/* For a given LV_SET, mark EXPR having unavailable target register.  */
static void
set_unavailable_target_for_expr (expr_t expr, regset lv_set)
{
  if (EXPR_SEPARABLE_P (expr))
    {
      if (REG_P (EXPR_LHS (expr))
          && register_unavailable_p (lv_set, EXPR_LHS (expr)))
	{
	  /* If it's an insn like r1 = use (r1, ...), and it exists in
	     different forms in each of the av_sets being merged, we can't say
	     whether original destination register is available or not.
	     However, this still works if destination register is not used
	     in the original expression: if the branch at which LV_SET we're
	     looking here is not actually 'other branch' in sense that same
	     expression is available through it (but it can't be determined
	     at computation stage because of transformations on one of the
	     branches), it still won't affect the availability.
	     Liveness of a register somewhere on a code motion path means
	     it's either read somewhere on a codemotion path, live on
	     'other' branch, live at the point immediately following
	     the original operation, or is read by the original operation.
	     The latter case is filtered out in the condition below.
	     It still doesn't cover the case when register is defined and used
	     somewhere within the code motion path, and in this case we could
	     miss a unifying code motion along both branches using a renamed
	     register, but it won't affect a code correctness since upon
	     an actual code motion a bookkeeping code would be generated.  */
	  if (register_unavailable_p (VINSN_REG_USES (EXPR_VINSN (expr)),
				      EXPR_LHS (expr)))
	    EXPR_TARGET_AVAILABLE (expr) = -1;
	  else
	    EXPR_TARGET_AVAILABLE (expr) = false;
	}
    }
  else
    {
      unsigned regno;
      reg_set_iterator rsi;

      EXECUTE_IF_SET_IN_REG_SET (VINSN_REG_SETS (EXPR_VINSN (expr)),
                                 0, regno, rsi)
        if (bitmap_bit_p (lv_set, regno))
          {
            EXPR_TARGET_AVAILABLE (expr) = false;
            break;
          }

      EXECUTE_IF_SET_IN_REG_SET (VINSN_REG_CLOBBERS (EXPR_VINSN (expr)),
                                 0, regno, rsi)
        if (bitmap_bit_p (lv_set, regno))
          {
            EXPR_TARGET_AVAILABLE (expr) = false;
            break;
          }
    }
}

/* Try to make EXPR speculative.  Return 1 when EXPR's pattern
   or dependence status have changed, 2 when also the target register
   became unavailable, 0 if nothing had to be changed.  */
int
speculate_expr (expr_t expr, ds_t ds)
{
  int res;
  rtx orig_insn_rtx;
  rtx spec_pat;
  ds_t target_ds, current_ds;

  /* Obtain the status we need to put on EXPR.   */
  target_ds = (ds & SPECULATIVE);
  current_ds = EXPR_SPEC_DONE_DS (expr);
  ds = ds_full_merge (current_ds, target_ds, NULL_RTX, NULL_RTX);

  orig_insn_rtx = EXPR_INSN_RTX (expr);

  res = sched_speculate_insn (orig_insn_rtx, ds, &spec_pat);

  switch (res)
    {
    case 0:
      EXPR_SPEC_DONE_DS (expr) = ds;
      return current_ds != ds ? 1 : 0;

    case 1:
      {
	rtx spec_insn_rtx = create_insn_rtx_from_pattern (spec_pat, NULL_RTX);
	vinsn_t spec_vinsn = create_vinsn_from_insn_rtx (spec_insn_rtx, false);

	change_vinsn_in_expr (expr, spec_vinsn);
	EXPR_SPEC_DONE_DS (expr) = ds;
        EXPR_NEEDS_SPEC_CHECK_P (expr) = true;

        /* Do not allow clobbering the address register of speculative
           insns.  */
        if (register_unavailable_p (VINSN_REG_USES (EXPR_VINSN (expr)),
				    expr_dest_reg (expr)))
          {
            EXPR_TARGET_AVAILABLE (expr) = false;
            return 2;
          }

	return 1;
      }

    case -1:
      return -1;

    default:
      gcc_unreachable ();
      return -1;
    }
}

/* Return a destination register, if any, of EXPR.  */
rtx
expr_dest_reg (expr_t expr)
{
  rtx dest = VINSN_LHS (EXPR_VINSN (expr));

  if (dest != NULL_RTX && REG_P (dest))
    return dest;

  return NULL_RTX;
}

/* Returns the REGNO of the R's destination.  */
unsigned
expr_dest_regno (expr_t expr)
{
  rtx dest = expr_dest_reg (expr);

  gcc_assert (dest != NULL_RTX);
  return REGNO (dest);
}

/* For a given LV_SET, mark all expressions in JOIN_SET, but not present in
   AV_SET having unavailable target register.  */
void
mark_unavailable_targets (av_set_t join_set, av_set_t av_set, regset lv_set)
{
  expr_t expr;
  av_set_iterator avi;

  FOR_EACH_EXPR (expr, avi, join_set)
    if (av_set_lookup (av_set, EXPR_VINSN (expr)) == NULL)
      set_unavailable_target_for_expr (expr, lv_set);
}


/* Returns true if REG (at least partially) is present in REGS.  */
bool
register_unavailable_p (regset regs, rtx reg)
{
  unsigned regno, end_regno;

  regno = REGNO (reg);
  if (bitmap_bit_p (regs, regno))
    return true;

  end_regno = END_REGNO (reg);

  while (++regno < end_regno)
    if (bitmap_bit_p (regs, regno))
      return true;

  return false;
}

/* Av set functions.  */

/* Add a new element to av set SETP.
   Return the element added.  */
static av_set_t
av_set_add_element (av_set_t *setp)
{
  /* Insert at the beginning of the list.  */
  _list_add (setp);
  return *setp;
}

/* Add EXPR to SETP.  */
void
av_set_add (av_set_t *setp, expr_t expr)
{
  av_set_t elem;

  gcc_assert (!INSN_NOP_P (EXPR_INSN_RTX (expr)));
  elem = av_set_add_element (setp);
  copy_expr (_AV_SET_EXPR (elem), expr);
}

/* Same, but do not copy EXPR.  */
static void
av_set_add_nocopy (av_set_t *setp, expr_t expr)
{
  av_set_t elem;

  elem = av_set_add_element (setp);
  *_AV_SET_EXPR (elem) = *expr;
}

/* Remove expr pointed to by IP from the av_set.  */
void
av_set_iter_remove (av_set_iterator *ip)
{
  clear_expr (_AV_SET_EXPR (*ip->lp));
  _list_iter_remove (ip);
}

/* Search for an expr in SET, such that it's equivalent to SOUGHT_VINSN in the
   sense of vinsn_equal_p function. Return NULL if no such expr is
   in SET was found.  */
expr_t
av_set_lookup (av_set_t set, vinsn_t sought_vinsn)
{
  expr_t expr;
  av_set_iterator i;

  FOR_EACH_EXPR (expr, i, set)
    if (vinsn_equal_p (EXPR_VINSN (expr), sought_vinsn))
      return expr;
  return NULL;
}

/* Same, but also remove the EXPR found.   */
static expr_t
av_set_lookup_and_remove (av_set_t *setp, vinsn_t sought_vinsn)
{
  expr_t expr;
  av_set_iterator i;

  FOR_EACH_EXPR_1 (expr, i, setp)
    if (vinsn_equal_p (EXPR_VINSN (expr), sought_vinsn))
      {
        _list_iter_remove_nofree (&i);
        return expr;
      }
  return NULL;
}

/* Search for an expr in SET, such that it's equivalent to EXPR in the
   sense of vinsn_equal_p function of their vinsns, but not EXPR itself.
   Returns NULL if no such expr is in SET was found.  */
static expr_t
av_set_lookup_other_equiv_expr (av_set_t set, expr_t expr)
{
  expr_t cur_expr;
  av_set_iterator i;

  FOR_EACH_EXPR (cur_expr, i, set)
    {
      if (cur_expr == expr)
        continue;
      if (vinsn_equal_p (EXPR_VINSN (cur_expr), EXPR_VINSN (expr)))
        return cur_expr;
    }

  return NULL;
}

/* If other expression is already in AVP, remove one of them.  */
expr_t
merge_with_other_exprs (av_set_t *avp, av_set_iterator *ip, expr_t expr)
{
  expr_t expr2;

  expr2 = av_set_lookup_other_equiv_expr (*avp, expr);
  if (expr2 != NULL)
    {
      /* Reset target availability on merge, since taking it only from one
	 of the exprs would be controversial for different code.  */
      EXPR_TARGET_AVAILABLE (expr2) = -1;
      EXPR_USEFULNESS (expr2) = 0;

      merge_expr (expr2, expr, NULL);

      /* Fix usefulness as it should be now REG_BR_PROB_BASE.  */
      EXPR_USEFULNESS (expr2) = REG_BR_PROB_BASE;

      av_set_iter_remove (ip);
      return expr2;
    }

  return expr;
}

/* Return true if there is an expr that correlates to VI in SET.  */
bool
av_set_is_in_p (av_set_t set, vinsn_t vi)
{
  return av_set_lookup (set, vi) != NULL;
}

/* Return a copy of SET.  */
av_set_t
av_set_copy (av_set_t set)
{
  expr_t expr;
  av_set_iterator i;
  av_set_t res = NULL;

  FOR_EACH_EXPR (expr, i, set)
    av_set_add (&res, expr);

  return res;
}

/* Join two av sets that do not have common elements by attaching second set
   (pointed to by FROMP) to the end of first set (TO_TAILP must point to
   _AV_SET_NEXT of first set's last element).  */
static void
join_distinct_sets (av_set_t *to_tailp, av_set_t *fromp)
{
  gcc_assert (*to_tailp == NULL);
  *to_tailp = *fromp;
  *fromp = NULL;
}

/* Makes set pointed to by TO to be the union of TO and FROM.  Clear av_set
   pointed to by FROMP afterwards.  */
void
av_set_union_and_clear (av_set_t *top, av_set_t *fromp, insn_t insn)
{
  expr_t expr1;
  av_set_iterator i;

  /* Delete from TOP all exprs, that present in FROMP.  */
  FOR_EACH_EXPR_1 (expr1, i, top)
    {
      expr_t expr2 = av_set_lookup (*fromp, EXPR_VINSN (expr1));

      if (expr2)
	{
          merge_expr (expr2, expr1, insn);
	  av_set_iter_remove (&i);
	}
    }

  join_distinct_sets (i.lp, fromp);
}

/* Same as above, but also update availability of target register in
   TOP judging by TO_LV_SET and FROM_LV_SET.  */
void
av_set_union_and_live (av_set_t *top, av_set_t *fromp, regset to_lv_set,
                       regset from_lv_set, insn_t insn)
{
  expr_t expr1;
  av_set_iterator i;
  av_set_t *to_tailp, in_both_set = NULL;

  /* Delete from TOP all expres, that present in FROMP.  */
  FOR_EACH_EXPR_1 (expr1, i, top)
    {
      expr_t expr2 = av_set_lookup_and_remove (fromp, EXPR_VINSN (expr1));

      if (expr2)
	{
          /* It may be that the expressions have different destination
             registers, in which case we need to check liveness here.  */
          if (EXPR_SEPARABLE_P (expr1))
            {
              int regno1 = (REG_P (EXPR_LHS (expr1))
                            ? (int) expr_dest_regno (expr1) : -1);
              int regno2 = (REG_P (EXPR_LHS (expr2))
                            ? (int) expr_dest_regno (expr2) : -1);

              /* ??? We don't have a way to check restrictions for
               *other* register on the current path, we did it only
               for the current target register.  Give up.  */
              if (regno1 != regno2)
                EXPR_TARGET_AVAILABLE (expr2) = -1;
            }
          else if (EXPR_INSN_RTX (expr1) != EXPR_INSN_RTX (expr2))
            EXPR_TARGET_AVAILABLE (expr2) = -1;

          merge_expr (expr2, expr1, insn);
          av_set_add_nocopy (&in_both_set, expr2);
	  av_set_iter_remove (&i);
	}
      else
        /* EXPR1 is present in TOP, but not in FROMP.  Check it on
           FROM_LV_SET.  */
        set_unavailable_target_for_expr (expr1, from_lv_set);
    }
  to_tailp = i.lp;

  /* These expressions are not present in TOP.  Check liveness
     restrictions on TO_LV_SET.  */
  FOR_EACH_EXPR (expr1, i, *fromp)
    set_unavailable_target_for_expr (expr1, to_lv_set);

  join_distinct_sets (i.lp, &in_both_set);
  join_distinct_sets (to_tailp, fromp);
}

/* Clear av_set pointed to by SETP.  */
void
av_set_clear (av_set_t *setp)
{
  expr_t expr;
  av_set_iterator i;

  FOR_EACH_EXPR_1 (expr, i, setp)
    av_set_iter_remove (&i);

  gcc_assert (*setp == NULL);
}

/* Leave only one non-speculative element in the SETP.  */
void
av_set_leave_one_nonspec (av_set_t *setp)
{
  expr_t expr;
  av_set_iterator i;
  bool has_one_nonspec = false;

  /* Keep all speculative exprs, and leave one non-speculative
     (the first one).  */
  FOR_EACH_EXPR_1 (expr, i, setp)
    {
      if (!EXPR_SPEC_DONE_DS (expr))
	{
  	  if (has_one_nonspec)
	    av_set_iter_remove (&i);
	  else
	    has_one_nonspec = true;
	}
    }
}

/* Return the N'th element of the SET.  */
expr_t
av_set_element (av_set_t set, int n)
{
  expr_t expr;
  av_set_iterator i;

  FOR_EACH_EXPR (expr, i, set)
    if (n-- == 0)
      return expr;

  gcc_unreachable ();
  return NULL;
}

/* Deletes all expressions from AVP that are conditional branches (IFs).  */
void
av_set_substract_cond_branches (av_set_t *avp)
{
  av_set_iterator i;
  expr_t expr;

  FOR_EACH_EXPR_1 (expr, i, avp)
    if (vinsn_cond_branch_p (EXPR_VINSN (expr)))
      av_set_iter_remove (&i);
}

/* Multiplies usefulness attribute of each member of av-set *AVP by
   value PROB / ALL_PROB.  */
void
av_set_split_usefulness (av_set_t av, int prob, int all_prob)
{
  av_set_iterator i;
  expr_t expr;

  FOR_EACH_EXPR (expr, i, av)
    EXPR_USEFULNESS (expr) = (all_prob
                              ? (EXPR_USEFULNESS (expr) * prob) / all_prob
                              : 0);
}

/* Leave in AVP only those expressions, which are present in AV,
   and return it, merging history expressions.  */
void
av_set_code_motion_filter (av_set_t *avp, av_set_t av)
{
  av_set_iterator i;
  expr_t expr, expr2;

  FOR_EACH_EXPR_1 (expr, i, avp)
    if ((expr2 = av_set_lookup (av, EXPR_VINSN (expr))) == NULL)
      av_set_iter_remove (&i);
    else
      /* When updating av sets in bookkeeping blocks, we can add more insns
	 there which will be transformed but the upper av sets will not
	 reflect those transformations.  We then fail to undo those
	 when searching for such insns.  So merge the history saved
	 in the av set of the block we are processing.  */
      merge_history_vect (&EXPR_HISTORY_OF_CHANGES (expr),
			  EXPR_HISTORY_OF_CHANGES (expr2));
}



/* Dependence hooks to initialize insn data.  */

/* This is used in hooks callable from dependence analysis when initializing
   instruction's data.  */
static struct
{
  /* Where the dependence was found (lhs/rhs).  */
  deps_where_t where;

  /* The actual data object to initialize.  */
  idata_t id;

  /* True when the insn should not be made clonable.  */
  bool force_unique_p;

  /* True when insn should be treated as of type USE, i.e. never renamed.  */
  bool force_use_p;
} deps_init_id_data;


/* Setup ID for INSN.  FORCE_UNIQUE_P is true when INSN should not be
   clonable.  */
static void
setup_id_for_insn (idata_t id, insn_t insn, bool force_unique_p)
{
  int type;

  /* Determine whether INSN could be cloned and return appropriate vinsn type.
     That clonable insns which can be separated into lhs and rhs have type SET.
     Other clonable insns have type USE.  */
  type = GET_CODE (insn);

  /* Only regular insns could be cloned.  */
  if (type == INSN && !force_unique_p)
    type = SET;
  else if (type == JUMP_INSN && simplejump_p (insn))
    type = PC;
  else if (type == DEBUG_INSN)
    type = !force_unique_p ? USE : INSN;

  IDATA_TYPE (id) = type;
  IDATA_REG_SETS (id) = get_clear_regset_from_pool ();
  IDATA_REG_USES (id) = get_clear_regset_from_pool ();
  IDATA_REG_CLOBBERS (id) = get_clear_regset_from_pool ();
}

/* Start initializing insn data.  */
static void
deps_init_id_start_insn (insn_t insn)
{
  gcc_assert (deps_init_id_data.where == DEPS_IN_NOWHERE);

  setup_id_for_insn (deps_init_id_data.id, insn,
                     deps_init_id_data.force_unique_p);
  deps_init_id_data.where = DEPS_IN_INSN;
}

/* Start initializing lhs data.  */
static void
deps_init_id_start_lhs (rtx lhs)
{
  gcc_assert (deps_init_id_data.where == DEPS_IN_INSN);
  gcc_assert (IDATA_LHS (deps_init_id_data.id) == NULL);

  if (IDATA_TYPE (deps_init_id_data.id) == SET)
    {
      IDATA_LHS (deps_init_id_data.id) = lhs;
      deps_init_id_data.where = DEPS_IN_LHS;
    }
}

/* Finish initializing lhs data.  */
static void
deps_init_id_finish_lhs (void)
{
  deps_init_id_data.where = DEPS_IN_INSN;
}

/* Note a set of REGNO.  */
static void
deps_init_id_note_reg_set (int regno)
{
  haifa_note_reg_set (regno);

  if (deps_init_id_data.where == DEPS_IN_RHS)
    deps_init_id_data.force_use_p = true;

  if (IDATA_TYPE (deps_init_id_data.id) != PC)
    SET_REGNO_REG_SET (IDATA_REG_SETS (deps_init_id_data.id), regno);

#ifdef STACK_REGS
  /* Make instructions that set stack registers to be ineligible for
     renaming to avoid issues with find_used_regs.  */
  if (IN_RANGE (regno, FIRST_STACK_REG, LAST_STACK_REG))
    deps_init_id_data.force_use_p = true;
#endif
}

/* Note a clobber of REGNO.  */
static void
deps_init_id_note_reg_clobber (int regno)
{
  haifa_note_reg_clobber (regno);

  if (deps_init_id_data.where == DEPS_IN_RHS)
    deps_init_id_data.force_use_p = true;

  if (IDATA_TYPE (deps_init_id_data.id) != PC)
    SET_REGNO_REG_SET (IDATA_REG_CLOBBERS (deps_init_id_data.id), regno);
}

/* Note a use of REGNO.  */
static void
deps_init_id_note_reg_use (int regno)
{
  haifa_note_reg_use (regno);

  if (IDATA_TYPE (deps_init_id_data.id) != PC)
    SET_REGNO_REG_SET (IDATA_REG_USES (deps_init_id_data.id), regno);
}

/* Start initializing rhs data.  */
static void
deps_init_id_start_rhs (rtx rhs)
{
  gcc_assert (deps_init_id_data.where == DEPS_IN_INSN);

  /* And there was no sel_deps_reset_to_insn ().  */
  if (IDATA_LHS (deps_init_id_data.id) != NULL)
    {
      IDATA_RHS (deps_init_id_data.id) = rhs;
      deps_init_id_data.where = DEPS_IN_RHS;
    }
}

/* Finish initializing rhs data.  */
static void
deps_init_id_finish_rhs (void)
{
  gcc_assert (deps_init_id_data.where == DEPS_IN_RHS
	      || deps_init_id_data.where == DEPS_IN_INSN);
  deps_init_id_data.where = DEPS_IN_INSN;
}

/* Finish initializing insn data.  */
static void
deps_init_id_finish_insn (void)
{
  gcc_assert (deps_init_id_data.where == DEPS_IN_INSN);

  if (IDATA_TYPE (deps_init_id_data.id) == SET)
    {
      rtx lhs = IDATA_LHS (deps_init_id_data.id);
      rtx rhs = IDATA_RHS (deps_init_id_data.id);

      if (lhs == NULL || rhs == NULL || !lhs_and_rhs_separable_p (lhs, rhs)
	  || deps_init_id_data.force_use_p)
	{
          /* This should be a USE, as we don't want to schedule its RHS
             separately.  However, we still want to have them recorded
             for the purposes of substitution.  That's why we don't
             simply call downgrade_to_use () here.  */
	  gcc_assert (IDATA_TYPE (deps_init_id_data.id) == SET);
	  gcc_assert (!lhs == !rhs);

	  IDATA_TYPE (deps_init_id_data.id) = USE;
	}
    }

  deps_init_id_data.where = DEPS_IN_NOWHERE;
}

/* This is dependence info used for initializing insn's data.  */
static struct sched_deps_info_def deps_init_id_sched_deps_info;

/* This initializes most of the static part of the above structure.  */
static const struct sched_deps_info_def const_deps_init_id_sched_deps_info =
  {
    NULL,

    deps_init_id_start_insn,
    deps_init_id_finish_insn,
    deps_init_id_start_lhs,
    deps_init_id_finish_lhs,
    deps_init_id_start_rhs,
    deps_init_id_finish_rhs,
    deps_init_id_note_reg_set,
    deps_init_id_note_reg_clobber,
    deps_init_id_note_reg_use,
    NULL, /* note_mem_dep */
    NULL, /* note_dep */

    0, /* use_cselib */
    0, /* use_deps_list */
    0 /* generate_spec_deps */
  };

/* Initialize INSN's lhs and rhs in ID.  When FORCE_UNIQUE_P is true,
   we don't actually need information about lhs and rhs.  */
static void
setup_id_lhs_rhs (idata_t id, insn_t insn, bool force_unique_p)
{
  rtx pat = PATTERN (insn);

  if (NONJUMP_INSN_P (insn)
      && GET_CODE (pat) == SET
      && !force_unique_p)
    {
      IDATA_RHS (id) = SET_SRC (pat);
      IDATA_LHS (id) = SET_DEST (pat);
    }
  else
    IDATA_LHS (id) = IDATA_RHS (id) = NULL;
}

/* Possibly downgrade INSN to USE.  */
static void
maybe_downgrade_id_to_use (idata_t id, insn_t insn)
{
  bool must_be_use = false;
  unsigned uid = INSN_UID (insn);
  df_ref *rec;
  rtx lhs = IDATA_LHS (id);
  rtx rhs = IDATA_RHS (id);

  /* We downgrade only SETs.  */
  if (IDATA_TYPE (id) != SET)
    return;

  if (!lhs || !lhs_and_rhs_separable_p (lhs, rhs))
    {
      IDATA_TYPE (id) = USE;
      return;
    }

  for (rec = DF_INSN_UID_DEFS (uid); *rec; rec++)
    {
      df_ref def = *rec;

      if (DF_REF_INSN (def)
          && DF_REF_FLAGS_IS_SET (def, DF_REF_PRE_POST_MODIFY)
          && loc_mentioned_in_p (DF_REF_LOC (def), IDATA_RHS (id)))
        {
          must_be_use = true;
          break;
        }

#ifdef STACK_REGS
      /* Make instructions that set stack registers to be ineligible for
	 renaming to avoid issues with find_used_regs.  */
      if (IN_RANGE (DF_REF_REGNO (def), FIRST_STACK_REG, LAST_STACK_REG))
	{
	  must_be_use = true;
	  break;
	}
#endif
    }

  if (must_be_use)
    IDATA_TYPE (id) = USE;
}

/* Setup register sets describing INSN in ID.  */
static void
setup_id_reg_sets (idata_t id, insn_t insn)
{
  unsigned uid = INSN_UID (insn);
  df_ref *rec;
  regset tmp = get_clear_regset_from_pool ();

  for (rec = DF_INSN_UID_DEFS (uid); *rec; rec++)
    {
      df_ref def = *rec;
      unsigned int regno = DF_REF_REGNO (def);

      /* Post modifies are treated like clobbers by sched-deps.c.  */
      if (DF_REF_FLAGS_IS_SET (def, (DF_REF_MUST_CLOBBER
                                     | DF_REF_PRE_POST_MODIFY)))
        SET_REGNO_REG_SET (IDATA_REG_CLOBBERS (id), regno);
      else if (! DF_REF_FLAGS_IS_SET (def, DF_REF_MAY_CLOBBER))
        {
	  SET_REGNO_REG_SET (IDATA_REG_SETS (id), regno);

#ifdef STACK_REGS
	  /* For stack registers, treat writes to them as writes
	     to the first one to be consistent with sched-deps.c.  */
	  if (IN_RANGE (regno, FIRST_STACK_REG, LAST_STACK_REG))
	    SET_REGNO_REG_SET (IDATA_REG_SETS (id), FIRST_STACK_REG);
#endif
	}
      /* Mark special refs that generate read/write def pair.  */
      if (DF_REF_FLAGS_IS_SET (def, DF_REF_CONDITIONAL)
          || regno == STACK_POINTER_REGNUM)
        bitmap_set_bit (tmp, regno);
    }

  for (rec = DF_INSN_UID_USES (uid); *rec; rec++)
    {
      df_ref use = *rec;
      unsigned int regno = DF_REF_REGNO (use);

      /* When these refs are met for the first time, skip them, as
         these uses are just counterparts of some defs.  */
      if (bitmap_bit_p (tmp, regno))
        bitmap_clear_bit (tmp, regno);
      else if (! DF_REF_FLAGS_IS_SET (use, DF_REF_CALL_STACK_USAGE))
	{
	  SET_REGNO_REG_SET (IDATA_REG_USES (id), regno);

#ifdef STACK_REGS
	  /* For stack registers, treat reads from them as reads from
	     the first one to be consistent with sched-deps.c.  */
	  if (IN_RANGE (regno, FIRST_STACK_REG, LAST_STACK_REG))
	    SET_REGNO_REG_SET (IDATA_REG_USES (id), FIRST_STACK_REG);
#endif
	}
    }

  return_regset_to_pool (tmp);
}

/* Initialize instruction data for INSN in ID using DF's data.  */
static void
init_id_from_df (idata_t id, insn_t insn, bool force_unique_p)
{
  gcc_assert (DF_INSN_UID_SAFE_GET (INSN_UID (insn)) != NULL);

  setup_id_for_insn (id, insn, force_unique_p);
  setup_id_lhs_rhs (id, insn, force_unique_p);

  if (INSN_NOP_P (insn))
    return;

  maybe_downgrade_id_to_use (id, insn);
  setup_id_reg_sets (id, insn);
}

/* Initialize instruction data for INSN in ID.  */
static void
deps_init_id (idata_t id, insn_t insn, bool force_unique_p)
{
  struct deps_desc _dc, *dc = &_dc;

  deps_init_id_data.where = DEPS_IN_NOWHERE;
  deps_init_id_data.id = id;
  deps_init_id_data.force_unique_p = force_unique_p;
  deps_init_id_data.force_use_p = false;

  init_deps (dc, false);

  memcpy (&deps_init_id_sched_deps_info,
	  &const_deps_init_id_sched_deps_info,
	  sizeof (deps_init_id_sched_deps_info));

  if (spec_info != NULL)
    deps_init_id_sched_deps_info.generate_spec_deps = 1;

  sched_deps_info = &deps_init_id_sched_deps_info;

  deps_analyze_insn (dc, insn);

  free_deps (dc);

  deps_init_id_data.id = NULL;
}


struct sched_scan_info_def
{
  /* This hook notifies scheduler frontend to extend its internal per basic
     block data structures.  This hook should be called once before a series of
     calls to bb_init ().  */
  void (*extend_bb) (void);

  /* This hook makes scheduler frontend to initialize its internal data
     structures for the passed basic block.  */
  void (*init_bb) (basic_block);

  /* This hook notifies scheduler frontend to extend its internal per insn data
     structures.  This hook should be called once before a series of calls to
     insn_init ().  */
  void (*extend_insn) (void);

  /* This hook makes scheduler frontend to initialize its internal data
     structures for the passed insn.  */
  void (*init_insn) (rtx);
};

/* A driver function to add a set of basic blocks (BBS) to the
   scheduling region.  */
static void
sched_scan (const struct sched_scan_info_def *ssi, bb_vec_t bbs)
{
  unsigned i;
  basic_block bb;

  if (ssi->extend_bb)
    ssi->extend_bb ();

  if (ssi->init_bb)
    FOR_EACH_VEC_ELT (bbs, i, bb)
      ssi->init_bb (bb);

  if (ssi->extend_insn)
    ssi->extend_insn ();

  if (ssi->init_insn)
    FOR_EACH_VEC_ELT (bbs, i, bb)
      {
	rtx insn;

	FOR_BB_INSNS (bb, insn)
	  ssi->init_insn (insn);
      }
}

/* Implement hooks for collecting fundamental insn properties like if insn is
   an ASM or is within a SCHED_GROUP.  */

/* True when a "one-time init" data for INSN was already inited.  */
static bool
first_time_insn_init (insn_t insn)
{
  return INSN_LIVE (insn) == NULL;
}

/* Hash an entry in a transformed_insns hashtable.  */
static hashval_t
hash_transformed_insns (const void *p)
{
  return VINSN_HASH_RTX (((const struct transformed_insns *) p)->vinsn_old);
}

/* Compare the entries in a transformed_insns hashtable.  */
static int
eq_transformed_insns (const void *p, const void *q)
{
  rtx i1 = VINSN_INSN_RTX (((const struct transformed_insns *) p)->vinsn_old);
  rtx i2 = VINSN_INSN_RTX (((const struct transformed_insns *) q)->vinsn_old);

  if (INSN_UID (i1) == INSN_UID (i2))
    return 1;
  return rtx_equal_p (PATTERN (i1), PATTERN (i2));
}

/* Free an entry in a transformed_insns hashtable.  */
static void
free_transformed_insns (void *p)
{
  struct transformed_insns *pti = (struct transformed_insns *) p;

  vinsn_detach (pti->vinsn_old);
  vinsn_detach (pti->vinsn_new);
  free (pti);
}

/* Init the s_i_d data for INSN which should be inited just once, when
   we first see the insn.  */
static void
init_first_time_insn_data (insn_t insn)
{
  /* This should not be set if this is the first time we init data for
     insn.  */
  gcc_assert (first_time_insn_init (insn));

  /* These are needed for nops too.  */
  INSN_LIVE (insn) = get_regset_from_pool ();
  INSN_LIVE_VALID_P (insn) = false;

  if (!INSN_NOP_P (insn))
    {
      INSN_ANALYZED_DEPS (insn) = BITMAP_ALLOC (NULL);
      INSN_FOUND_DEPS (insn) = BITMAP_ALLOC (NULL);
      INSN_TRANSFORMED_INSNS (insn)
        = htab_create (16, hash_transformed_insns,
                       eq_transformed_insns, free_transformed_insns);
      init_deps (&INSN_DEPS_CONTEXT (insn), true);
    }
}

/* Free almost all above data for INSN that is scheduled already.
   Used for extra-large basic blocks.  */
void
free_data_for_scheduled_insn (insn_t insn)
{
  gcc_assert (! first_time_insn_init (insn));

  if (! INSN_ANALYZED_DEPS (insn))
    return;

  BITMAP_FREE (INSN_ANALYZED_DEPS (insn));
  BITMAP_FREE (INSN_FOUND_DEPS (insn));
  htab_delete (INSN_TRANSFORMED_INSNS (insn));

  /* This is allocated only for bookkeeping insns.  */
  if (INSN_ORIGINATORS (insn))
    BITMAP_FREE (INSN_ORIGINATORS (insn));
  free_deps (&INSN_DEPS_CONTEXT (insn));

  INSN_ANALYZED_DEPS (insn) = NULL;

  /* Clear the readonly flag so we would ICE when trying to recalculate
     the deps context (as we believe that it should not happen).  */
  (&INSN_DEPS_CONTEXT (insn))->readonly = 0;
}

/* Free the same data as above for INSN.  */
static void
free_first_time_insn_data (insn_t insn)
{
  gcc_assert (! first_time_insn_init (insn));

  free_data_for_scheduled_insn (insn);
  return_regset_to_pool (INSN_LIVE (insn));
  INSN_LIVE (insn) = NULL;
  INSN_LIVE_VALID_P (insn) = false;
}

/* Initialize region-scope data structures for basic blocks.  */
static void
init_global_and_expr_for_bb (basic_block bb)
{
  if (sel_bb_empty_p (bb))
    return;

  invalidate_av_set (bb);
}

/* Data for global dependency analysis (to initialize CANT_MOVE and
   SCHED_GROUP_P).  */
static struct
{
  /* Previous insn.  */
  insn_t prev_insn;
} init_global_data;

/* Determine if INSN is in the sched_group, is an asm or should not be
   cloned.  After that initialize its expr.  */
static void
init_global_and_expr_for_insn (insn_t insn)
{
  if (LABEL_P (insn))
    return;

  if (NOTE_INSN_BASIC_BLOCK_P (insn))
    {
      init_global_data.prev_insn = NULL_RTX;
      return;
    }

  gcc_assert (INSN_P (insn));

  if (SCHED_GROUP_P (insn))
    /* Setup a sched_group.  */
    {
      insn_t prev_insn = init_global_data.prev_insn;

      if (prev_insn)
	INSN_SCHED_NEXT (prev_insn) = insn;

      init_global_data.prev_insn = insn;
    }
  else
    init_global_data.prev_insn = NULL_RTX;

  if (GET_CODE (PATTERN (insn)) == ASM_INPUT
      || asm_noperands (PATTERN (insn)) >= 0)
    /* Mark INSN as an asm.  */
    INSN_ASM_P (insn) = true;

  {
    bool force_unique_p;
    ds_t spec_done_ds;

    /* Certain instructions cannot be cloned, and frame related insns and
       the insn adjacent to NOTE_INSN_EPILOGUE_BEG cannot be moved out of
       their block.  */
    if (prologue_epilogue_contains (insn))
      {
        if (RTX_FRAME_RELATED_P (insn))
          CANT_MOVE (insn) = 1;
        else
          {
            rtx note;
            for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
              if (REG_NOTE_KIND (note) == REG_SAVE_NOTE
                  && ((enum insn_note) INTVAL (XEXP (note, 0))
                      == NOTE_INSN_EPILOGUE_BEG))
                {
                  CANT_MOVE (insn) = 1;
                  break;
                }
          }
        force_unique_p = true;
      }
    else
      if (CANT_MOVE (insn)
          || INSN_ASM_P (insn)
          || SCHED_GROUP_P (insn)
	  || CALL_P (insn)
          /* Exception handling insns are always unique.  */
          || (cfun->can_throw_non_call_exceptions && can_throw_internal (insn))
          /* TRAP_IF though have an INSN code is control_flow_insn_p ().  */
          || control_flow_insn_p (insn)
          || volatile_insn_p (PATTERN (insn))
          || (targetm.cannot_copy_insn_p
              && targetm.cannot_copy_insn_p (insn)))
        force_unique_p = true;
      else
        force_unique_p = false;

    if (targetm.sched.get_insn_spec_ds)
      {
	spec_done_ds = targetm.sched.get_insn_spec_ds (insn);
	spec_done_ds = ds_get_max_dep_weak (spec_done_ds);
      }
    else
      spec_done_ds = 0;

    /* Initialize INSN's expr.  */
    init_expr (INSN_EXPR (insn), vinsn_create (insn, force_unique_p), 0,
	       REG_BR_PROB_BASE, INSN_PRIORITY (insn), 0, BLOCK_NUM (insn),
	       spec_done_ds, 0, 0, vNULL, true,
	       false, false, false, CANT_MOVE (insn));
  }

  init_first_time_insn_data (insn);
}

/* Scan the region and initialize instruction data for basic blocks BBS.  */
void
sel_init_global_and_expr (bb_vec_t bbs)
{
  /* ??? It would be nice to implement push / pop scheme for sched_infos.  */
  const struct sched_scan_info_def ssi =
    {
      NULL, /* extend_bb */
      init_global_and_expr_for_bb, /* init_bb */
      extend_insn_data, /* extend_insn */
      init_global_and_expr_for_insn /* init_insn */
    };

  sched_scan (&ssi, bbs);
}

/* Finalize region-scope data structures for basic blocks.  */
static void
finish_global_and_expr_for_bb (basic_block bb)
{
  av_set_clear (&BB_AV_SET (bb));
  BB_AV_LEVEL (bb) = 0;
}

/* Finalize INSN's data.  */
static void
finish_global_and_expr_insn (insn_t insn)
{
  if (LABEL_P (insn) || NOTE_INSN_BASIC_BLOCK_P (insn))
    return;

  gcc_assert (INSN_P (insn));

  if (INSN_LUID (insn) > 0)
    {
      free_first_time_insn_data (insn);
      INSN_WS_LEVEL (insn) = 0;
      CANT_MOVE (insn) = 0;

      /* We can no longer assert this, as vinsns of this insn could be
         easily live in other insn's caches.  This should be changed to
         a counter-like approach among all vinsns.  */
      gcc_assert (true || VINSN_COUNT (INSN_VINSN (insn)) == 1);
      clear_expr (INSN_EXPR (insn));
    }
}

/* Finalize per instruction data for the whole region.  */
void
sel_finish_global_and_expr (void)
{
  {
    bb_vec_t bbs;
    int i;

    bbs.create (current_nr_blocks);

    for (i = 0; i < current_nr_blocks; i++)
      bbs.quick_push (BASIC_BLOCK_FOR_FN (cfun, BB_TO_BLOCK (i)));

    /* Clear AV_SETs and INSN_EXPRs.  */
    {
      const struct sched_scan_info_def ssi =
	{
	  NULL, /* extend_bb */
	  finish_global_and_expr_for_bb, /* init_bb */
	  NULL, /* extend_insn */
	  finish_global_and_expr_insn /* init_insn */
	};

      sched_scan (&ssi, bbs);
    }

    bbs.release ();
  }

  finish_insns ();
}


/* In the below hooks, we merely calculate whether or not a dependence
   exists, and in what part of insn.  However, we will need more data
   when we'll start caching dependence requests.  */

/* Container to hold information for dependency analysis.  */
static struct
{
  deps_t dc;

  /* A variable to track which part of rtx we are scanning in
     sched-deps.c: sched_analyze_insn ().  */
  deps_where_t where;

  /* Current producer.  */
  insn_t pro;

  /* Current consumer.  */
  vinsn_t con;

  /* Is SEL_DEPS_HAS_DEP_P[DEPS_IN_X] is true, then X has a dependence.
     X is from { INSN, LHS, RHS }.  */
  ds_t has_dep_p[DEPS_IN_NOWHERE];
} has_dependence_data;

/* Start analyzing dependencies of INSN.  */
static void
has_dependence_start_insn (insn_t insn ATTRIBUTE_UNUSED)
{
  gcc_assert (has_dependence_data.where == DEPS_IN_NOWHERE);

  has_dependence_data.where = DEPS_IN_INSN;
}

/* Finish analyzing dependencies of an insn.  */
static void
has_dependence_finish_insn (void)
{
  gcc_assert (has_dependence_data.where == DEPS_IN_INSN);

  has_dependence_data.where = DEPS_IN_NOWHERE;
}

/* Start analyzing dependencies of LHS.  */
static void
has_dependence_start_lhs (rtx lhs ATTRIBUTE_UNUSED)
{
  gcc_assert (has_dependence_data.where == DEPS_IN_INSN);

  if (VINSN_LHS (has_dependence_data.con) != NULL)
    has_dependence_data.where = DEPS_IN_LHS;
}

/* Finish analyzing dependencies of an lhs.  */
static void
has_dependence_finish_lhs (void)
{
  has_dependence_data.where = DEPS_IN_INSN;
}

/* Start analyzing dependencies of RHS.  */
static void
has_dependence_start_rhs (rtx rhs ATTRIBUTE_UNUSED)
{
  gcc_assert (has_dependence_data.where == DEPS_IN_INSN);

  if (VINSN_RHS (has_dependence_data.con) != NULL)
    has_dependence_data.where = DEPS_IN_RHS;
}

/* Start analyzing dependencies of an rhs.  */
static void
has_dependence_finish_rhs (void)
{
  gcc_assert (has_dependence_data.where == DEPS_IN_RHS
	      || has_dependence_data.where == DEPS_IN_INSN);

  has_dependence_data.where = DEPS_IN_INSN;
}

/* Note a set of REGNO.  */
static void
has_dependence_note_reg_set (int regno)
{
  struct deps_reg *reg_last = &has_dependence_data.dc->reg_last[regno];

  if (!sched_insns_conditions_mutex_p (has_dependence_data.pro,
				       VINSN_INSN_RTX
				       (has_dependence_data.con)))
    {
      ds_t *dsp = &has_dependence_data.has_dep_p[has_dependence_data.where];

      if (reg_last->sets != NULL
	  || reg_last->clobbers != NULL)
	*dsp = (*dsp & ~SPECULATIVE) | DEP_OUTPUT;

      if (reg_last->uses || reg_last->implicit_sets)
	*dsp = (*dsp & ~SPECULATIVE) | DEP_ANTI;
    }
}

/* Note a clobber of REGNO.  */
static void
has_dependence_note_reg_clobber (int regno)
{
  struct deps_reg *reg_last = &has_dependence_data.dc->reg_last[regno];

  if (!sched_insns_conditions_mutex_p (has_dependence_data.pro,
				       VINSN_INSN_RTX
				       (has_dependence_data.con)))
    {
      ds_t *dsp = &has_dependence_data.has_dep_p[has_dependence_data.where];

      if (reg_last->sets)
	*dsp = (*dsp & ~SPECULATIVE) | DEP_OUTPUT;

      if (reg_last->uses || reg_last->implicit_sets)
	*dsp = (*dsp & ~SPECULATIVE) | DEP_ANTI;
    }
}

/* Note a use of REGNO.  */
static void
has_dependence_note_reg_use (int regno)
{
  struct deps_reg *reg_last = &has_dependence_data.dc->reg_last[regno];

  if (!sched_insns_conditions_mutex_p (has_dependence_data.pro,
				       VINSN_INSN_RTX
				       (has_dependence_data.con)))
    {
      ds_t *dsp = &has_dependence_data.has_dep_p[has_dependence_data.where];

      if (reg_last->sets)
	*dsp = (*dsp & ~SPECULATIVE) | DEP_TRUE;

      if (reg_last->clobbers || reg_last->implicit_sets)
	*dsp = (*dsp & ~SPECULATIVE) | DEP_ANTI;

      /* Merge BE_IN_SPEC bits into *DSP when the dependency producer
	 is actually a check insn.  We need to do this for any register
	 read-read dependency with the check unless we track properly
	 all registers written by BE_IN_SPEC-speculated insns, as
	 we don't have explicit dependence lists.  See PR 53975.  */
      if (reg_last->uses)
	{
	  ds_t pro_spec_checked_ds;

	  pro_spec_checked_ds = INSN_SPEC_CHECKED_DS (has_dependence_data.pro);
	  pro_spec_checked_ds = ds_get_max_dep_weak (pro_spec_checked_ds);

	  if (pro_spec_checked_ds != 0)
	    *dsp = ds_full_merge (*dsp, pro_spec_checked_ds,
				  NULL_RTX, NULL_RTX);
	}
    }
}

/* Note a memory dependence.  */
static void
has_dependence_note_mem_dep (rtx mem ATTRIBUTE_UNUSED,
			     rtx pending_mem ATTRIBUTE_UNUSED,
			     insn_t pending_insn ATTRIBUTE_UNUSED,
			     ds_t ds ATTRIBUTE_UNUSED)
{
  if (!sched_insns_conditions_mutex_p (has_dependence_data.pro,
				       VINSN_INSN_RTX (has_dependence_data.con)))
    {
      ds_t *dsp = &has_dependence_data.has_dep_p[has_dependence_data.where];

      *dsp = ds_full_merge (ds, *dsp, pending_mem, mem);
    }
}

/* Note a dependence.  */
static void
has_dependence_note_dep (insn_t pro ATTRIBUTE_UNUSED,
			 ds_t ds ATTRIBUTE_UNUSED)
{
  if (!sched_insns_conditions_mutex_p (has_dependence_data.pro,
				       VINSN_INSN_RTX (has_dependence_data.con)))
    {
      ds_t *dsp = &has_dependence_data.has_dep_p[has_dependence_data.where];

      *dsp = ds_full_merge (ds, *dsp, NULL_RTX, NULL_RTX);
    }
}

/* Mark the insn as having a hard dependence that prevents speculation.  */
void
sel_mark_hard_insn (rtx insn)
{
  int i;

  /* Only work when we're in has_dependence_p mode.
     ??? This is a hack, this should actually be a hook.  */
  if (!has_dependence_data.dc || !has_dependence_data.pro)
    return;

  gcc_assert (insn == VINSN_INSN_RTX (has_dependence_data.con));
  gcc_assert (has_dependence_data.where == DEPS_IN_INSN);

  for (i = 0; i < DEPS_IN_NOWHERE; i++)
    has_dependence_data.has_dep_p[i] &= ~SPECULATIVE;
}

/* This structure holds the hooks for the dependency analysis used when
   actually processing dependencies in the scheduler.  */
static struct sched_deps_info_def has_dependence_sched_deps_info;

/* This initializes most of the fields of the above structure.  */
static const struct sched_deps_info_def const_has_dependence_sched_deps_info =
  {
    NULL,

    has_dependence_start_insn,
    has_dependence_finish_insn,
    has_dependence_start_lhs,
    has_dependence_finish_lhs,
    has_dependence_start_rhs,
    has_dependence_finish_rhs,
    has_dependence_note_reg_set,
    has_dependence_note_reg_clobber,
    has_dependence_note_reg_use,
    has_dependence_note_mem_dep,
    has_dependence_note_dep,

    0, /* use_cselib */
    0, /* use_deps_list */
    0 /* generate_spec_deps */
  };

/* Initialize has_dependence_sched_deps_info with extra spec field.  */
static void
setup_has_dependence_sched_deps_info (void)
{
  memcpy (&has_dependence_sched_deps_info,
	  &const_has_dependence_sched_deps_info,
	  sizeof (has_dependence_sched_deps_info));

  if (spec_info != NULL)
    has_dependence_sched_deps_info.generate_spec_deps = 1;

  sched_deps_info = &has_dependence_sched_deps_info;
}

/* Remove all dependences found and recorded in has_dependence_data array.  */
void
sel_clear_has_dependence (void)
{
  int i;

  for (i = 0; i < DEPS_IN_NOWHERE; i++)
    has_dependence_data.has_dep_p[i] = 0;
}

/* Return nonzero if EXPR has is dependent upon PRED.  Return the pointer
   to the dependence information array in HAS_DEP_PP.  */
ds_t
has_dependence_p (expr_t expr, insn_t pred, ds_t **has_dep_pp)
{
  int i;
  ds_t ds;
  struct deps_desc *dc;

  if (INSN_SIMPLEJUMP_P (pred))
    /* Unconditional jump is just a transfer of control flow.
       Ignore it.  */
    return false;

  dc = &INSN_DEPS_CONTEXT (pred);

  /* We init this field lazily.  */
  if (dc->reg_last == NULL)
    init_deps_reg_last (dc);

  if (!dc->readonly)
    {
      has_dependence_data.pro = NULL;
      /* Initialize empty dep context with information about PRED.  */
      advance_deps_context (dc, pred);
      dc->readonly = 1;
    }

  has_dependence_data.where = DEPS_IN_NOWHERE;
  has_dependence_data.pro = pred;
  has_dependence_data.con = EXPR_VINSN (expr);
  has_dependence_data.dc = dc;

  sel_clear_has_dependence ();

  /* Now catch all dependencies that would be generated between PRED and
     INSN.  */
  setup_has_dependence_sched_deps_info ();
  deps_analyze_insn (dc, EXPR_INSN_RTX (expr));
  has_dependence_data.dc = NULL;

  /* When a barrier was found, set DEPS_IN_INSN bits.  */
  if (dc->last_reg_pending_barrier == TRUE_BARRIER)
    has_dependence_data.has_dep_p[DEPS_IN_INSN] = DEP_TRUE;
  else if (dc->last_reg_pending_barrier == MOVE_BARRIER)
    has_dependence_data.has_dep_p[DEPS_IN_INSN] = DEP_ANTI;

  /* Do not allow stores to memory to move through checks.  Currently
     we don't move this to sched-deps.c as the check doesn't have
     obvious places to which this dependence can be attached.
     FIMXE: this should go to a hook.  */
  if (EXPR_LHS (expr)
      && MEM_P (EXPR_LHS (expr))
      && sel_insn_is_speculation_check (pred))
    has_dependence_data.has_dep_p[DEPS_IN_INSN] = DEP_ANTI;

  *has_dep_pp = has_dependence_data.has_dep_p;
  ds = 0;
  for (i = 0; i < DEPS_IN_NOWHERE; i++)
    ds = ds_full_merge (ds, has_dependence_data.has_dep_p[i],
			NULL_RTX, NULL_RTX);

  return ds;
}


/* Dependence hooks implementation that checks dependence latency constraints
   on the insns being scheduled.  The entry point for these routines is
   tick_check_p predicate.  */

static struct
{
  /* An expr we are currently checking.  */
  expr_t expr;

  /* A minimal cycle for its scheduling.  */
  int cycle;

  /* Whether we have seen a true dependence while checking.  */
  bool seen_true_dep_p;
} tick_check_data;

/* Update minimal scheduling cycle for tick_check_insn given that it depends
   on PRO with status DS and weight DW.  */
static void
tick_check_dep_with_dw (insn_t pro_insn, ds_t ds, dw_t dw)
{
  expr_t con_expr = tick_check_data.expr;
  insn_t con_insn = EXPR_INSN_RTX (con_expr);

  if (con_insn != pro_insn)
    {
      enum reg_note dt;
      int tick;

      if (/* PROducer was removed from above due to pipelining.  */
	  !INSN_IN_STREAM_P (pro_insn)
	  /* Or PROducer was originally on the next iteration regarding the
	     CONsumer.  */
	  || (INSN_SCHED_TIMES (pro_insn)
	      - EXPR_SCHED_TIMES (con_expr)) > 1)
	/* Don't count this dependence.  */
        return;

      dt = ds_to_dt (ds);
      if (dt == REG_DEP_TRUE)
        tick_check_data.seen_true_dep_p = true;

      gcc_assert (INSN_SCHED_CYCLE (pro_insn) > 0);

      {
	dep_def _dep, *dep = &_dep;

	init_dep (dep, pro_insn, con_insn, dt);

	tick = INSN_SCHED_CYCLE (pro_insn) + dep_cost_1 (dep, dw);
      }

      /* When there are several kinds of dependencies between pro and con,
         only REG_DEP_TRUE should be taken into account.  */
      if (tick > tick_check_data.cycle
	  && (dt == REG_DEP_TRUE || !tick_check_data.seen_true_dep_p))
	tick_check_data.cycle = tick;
    }
}

/* An implementation of note_dep hook.  */
static void
tick_check_note_dep (insn_t pro, ds_t ds)
{
  tick_check_dep_with_dw (pro, ds, 0);
}

/* An implementation of note_mem_dep hook.  */
static void
tick_check_note_mem_dep (rtx mem1, rtx mem2, insn_t pro, ds_t ds)
{
  dw_t dw;

  dw = (ds_to_dt (ds) == REG_DEP_TRUE
        ? estimate_dep_weak (mem1, mem2)
        : 0);

  tick_check_dep_with_dw (pro, ds, dw);
}

/* This structure contains hooks for dependence analysis used when determining
   whether an insn is ready for scheduling.  */
static struct sched_deps_info_def tick_check_sched_deps_info =
  {
    NULL,

    NULL,
    NULL,
    NULL,
    NULL,
    NULL,
    NULL,
    haifa_note_reg_set,
    haifa_note_reg_clobber,
    haifa_note_reg_use,
    tick_check_note_mem_dep,
    tick_check_note_dep,

    0, 0, 0
  };

/* Estimate number of cycles from the current cycle of FENCE until EXPR can be
   scheduled.  Return 0 if all data from producers in DC is ready.  */
int
tick_check_p (expr_t expr, deps_t dc, fence_t fence)
{
  int cycles_left;
  /* Initialize variables.  */
  tick_check_data.expr = expr;
  tick_check_data.cycle = 0;
  tick_check_data.seen_true_dep_p = false;
  sched_deps_info = &tick_check_sched_deps_info;

  gcc_assert (!dc->readonly);
  dc->readonly = 1;
  deps_analyze_insn (dc, EXPR_INSN_RTX (expr));
  dc->readonly = 0;

  cycles_left = tick_check_data.cycle - FENCE_CYCLE (fence);

  return cycles_left >= 0 ? cycles_left : 0;
}


/* Functions to work with insns.  */

/* Returns true if LHS of INSN is the same as DEST of an insn
   being moved.  */
bool
lhs_of_insn_equals_to_dest_p (insn_t insn, rtx dest)
{
  rtx lhs = INSN_LHS (insn);

  if (lhs == NULL || dest == NULL)
    return false;

  return rtx_equal_p (lhs, dest);
}

/* Return s_i_d entry of INSN.  Callable from debugger.  */
sel_insn_data_def
insn_sid (insn_t insn)
{
  return *SID (insn);
}

/* True when INSN is a speculative check.  We can tell this by looking
   at the data structures of the selective scheduler, not by examining
   the pattern.  */
bool
sel_insn_is_speculation_check (rtx insn)
{
  return s_i_d.exists () && !! INSN_SPEC_CHECKED_DS (insn);
}

/* Extracts machine mode MODE and destination location DST_LOC
   for given INSN.  */
void
get_dest_and_mode (rtx insn, rtx *dst_loc, enum machine_mode *mode)
{
  rtx pat = PATTERN (insn);

  gcc_assert (dst_loc);
  gcc_assert (GET_CODE (pat) == SET);

  *dst_loc = SET_DEST (pat);

  gcc_assert (*dst_loc);
  gcc_assert (MEM_P (*dst_loc) || REG_P (*dst_loc));

  if (mode)
    *mode = GET_MODE (*dst_loc);
}

/* Returns true when moving through JUMP will result in bookkeeping
   creation.  */
bool
bookkeeping_can_be_created_if_moved_through_p (insn_t jump)
{
  insn_t succ;
  succ_iterator si;

  FOR_EACH_SUCC (succ, si, jump)
    if (sel_num_cfg_preds_gt_1 (succ))
      return true;

  return false;
}

/* Return 'true' if INSN is the only one in its basic block.  */
static bool
insn_is_the_only_one_in_bb_p (insn_t insn)
{
  return sel_bb_head_p (insn) && sel_bb_end_p (insn);
}

#ifdef ENABLE_CHECKING
/* Check that the region we're scheduling still has at most one
   backedge.  */
static void
verify_backedges (void)
{
  if (pipelining_p)
    {
      int i, n = 0;
      edge e;
      edge_iterator ei;

      for (i = 0; i < current_nr_blocks; i++)
        FOR_EACH_EDGE (e, ei, BASIC_BLOCK_FOR_FN (cfun, BB_TO_BLOCK (i))->succs)
          if (in_current_region_p (e->dest)
              && BLOCK_TO_BB (e->dest->index) < i)
            n++;

      gcc_assert (n <= 1);
    }
}
#endif


/* Functions to work with control flow.  */

/* Recompute BLOCK_TO_BB and BB_FOR_BLOCK for current region so that blocks
   are sorted in topological order (it might have been invalidated by
   redirecting an edge).  */
static void
sel_recompute_toporder (void)
{
  int i, n, rgn;
  int *postorder, n_blocks;

  postorder = XALLOCAVEC (int, n_basic_blocks_for_fn (cfun));
  n_blocks = post_order_compute (postorder, false, false);

  rgn = CONTAINING_RGN (BB_TO_BLOCK (0));
  for (n = 0, i = n_blocks - 1; i >= 0; i--)
    if (CONTAINING_RGN (postorder[i]) == rgn)
      {
	BLOCK_TO_BB (postorder[i]) = n;
	BB_TO_BLOCK (n) = postorder[i];
	n++;
      }

  /* Assert that we updated info for all blocks.  We may miss some blocks if
     this function is called when redirecting an edge made a block
     unreachable, but that block is not deleted yet.  */
  gcc_assert (n == RGN_NR_BLOCKS (rgn));
}

/* Tidy the possibly empty block BB.  */
static bool
maybe_tidy_empty_bb (basic_block bb)
{
  basic_block succ_bb, pred_bb, note_bb;
  vec<basic_block> dom_bbs;
  edge e;
  edge_iterator ei;
  bool rescan_p;

  /* Keep empty bb only if this block immediately precedes EXIT and
     has incoming non-fallthrough edge, or it has no predecessors or
     successors.  Otherwise remove it.  */
  if (!sel_bb_empty_p (bb)
      || (single_succ_p (bb)
	  && single_succ (bb) == EXIT_BLOCK_PTR_FOR_FN (cfun)
          && (!single_pred_p (bb)
              || !(single_pred_edge (bb)->flags & EDGE_FALLTHRU)))
      || EDGE_COUNT (bb->preds) == 0
      || EDGE_COUNT (bb->succs) == 0)
    return false;

  /* Do not attempt to redirect complex edges.  */
  FOR_EACH_EDGE (e, ei, bb->preds)
    if (e->flags & EDGE_COMPLEX)
      return false;
    else if (e->flags & EDGE_FALLTHRU)
      {
	rtx note;
	/* If prev bb ends with asm goto, see if any of the
	   ASM_OPERANDS_LABELs don't point to the fallthru
	   label.  Do not attempt to redirect it in that case.  */
	if (JUMP_P (BB_END (e->src))
	    && (note = extract_asm_operands (PATTERN (BB_END (e->src)))))
	  {
	    int i, n = ASM_OPERANDS_LABEL_LENGTH (note);

	    for (i = 0; i < n; ++i)
	      if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (bb))
		return false;
	  }
      }

  free_data_sets (bb);

  /* Do not delete BB if it has more than one successor.
     That can occur when we moving a jump.  */
  if (!single_succ_p (bb))
    {
      gcc_assert (can_merge_blocks_p (bb->prev_bb, bb));
      sel_merge_blocks (bb->prev_bb, bb);
      return true;
    }

  succ_bb = single_succ (bb);
  rescan_p = true;
  pred_bb = NULL;
  dom_bbs.create (0);

  /* Save a pred/succ from the current region to attach the notes to.  */
  note_bb = NULL;
  FOR_EACH_EDGE (e, ei, bb->preds)
    if (in_current_region_p (e->src))
      {
	note_bb = e->src;
	break;
      }
  if (note_bb == NULL)
    note_bb = succ_bb;

  /* Redirect all non-fallthru edges to the next bb.  */
  while (rescan_p)
    {
      rescan_p = false;

      FOR_EACH_EDGE (e, ei, bb->preds)
        {
          pred_bb = e->src;

          if (!(e->flags & EDGE_FALLTHRU))
            {
	      /* We can not invalidate computed topological order by moving
	         the edge destination block (E->SUCC) along a fallthru edge.

		 We will update dominators here only when we'll get
		 an unreachable block when redirecting, otherwise
		 sel_redirect_edge_and_branch will take care of it.  */
	      if (e->dest != bb
		  && single_pred_p (e->dest))
		dom_bbs.safe_push (e->dest);
              sel_redirect_edge_and_branch (e, succ_bb);
              rescan_p = true;
              break;
            }
	  /* If the edge is fallthru, but PRED_BB ends in a conditional jump
	     to BB (so there is no non-fallthru edge from PRED_BB to BB), we
	     still have to adjust it.  */
	  else if (single_succ_p (pred_bb) && any_condjump_p (BB_END (pred_bb)))
	    {
	      /* If possible, try to remove the unneeded conditional jump.  */
	      if (INSN_SCHED_TIMES (BB_END (pred_bb)) == 0
		  && !IN_CURRENT_FENCE_P (BB_END (pred_bb)))
		{
		  if (!sel_remove_insn (BB_END (pred_bb), false, false))
		    tidy_fallthru_edge (e);
		}
	      else
		sel_redirect_edge_and_branch (e, succ_bb);
	      rescan_p = true;
	      break;
	    }
        }
    }

  if (can_merge_blocks_p (bb->prev_bb, bb))
    sel_merge_blocks (bb->prev_bb, bb);
  else
    {
      /* This is a block without fallthru predecessor.  Just delete it.  */
      gcc_assert (note_bb);
      move_bb_info (note_bb, bb);
      remove_empty_bb (bb, true);
    }

  if (!dom_bbs.is_empty ())
    {
      dom_bbs.safe_push (succ_bb);
      iterate_fix_dominators (CDI_DOMINATORS, dom_bbs, false);
      dom_bbs.release ();
    }

  return true;
}

/* Tidy the control flow after we have removed original insn from
   XBB.  Return true if we have removed some blocks.  When FULL_TIDYING
   is true, also try to optimize control flow on non-empty blocks.  */
bool
tidy_control_flow (basic_block xbb, bool full_tidying)
{
  bool changed = true;
  insn_t first, last;

  /* First check whether XBB is empty.  */
  changed = maybe_tidy_empty_bb (xbb);
  if (changed || !full_tidying)
    return changed;

  /* Check if there is a unnecessary jump after insn left.  */
  if (bb_has_removable_jump_to_p (xbb, xbb->next_bb)
      && INSN_SCHED_TIMES (BB_END (xbb)) == 0
      && !IN_CURRENT_FENCE_P (BB_END (xbb)))
    {
      if (sel_remove_insn (BB_END (xbb), false, false))
        return true;
      tidy_fallthru_edge (EDGE_SUCC (xbb, 0));
    }

  first = sel_bb_head (xbb);
  last = sel_bb_end (xbb);
  if (MAY_HAVE_DEBUG_INSNS)
    {
      if (first != last && DEBUG_INSN_P (first))
	do
	  first = NEXT_INSN (first);
	while (first != last && (DEBUG_INSN_P (first) || NOTE_P (first)));

      if (first != last && DEBUG_INSN_P (last))
	do
	  last = PREV_INSN (last);
	while (first != last && (DEBUG_INSN_P (last) || NOTE_P (last)));
    }
  /* Check if there is an unnecessary jump in previous basic block leading
     to next basic block left after removing INSN from stream.
     If it is so, remove that jump and redirect edge to current
     basic block (where there was INSN before deletion).  This way
     when NOP will be deleted several instructions later with its
     basic block we will not get a jump to next instruction, which
     can be harmful.  */
  if (first == last
      && !sel_bb_empty_p (xbb)
      && INSN_NOP_P (last)
      /* Flow goes fallthru from current block to the next.  */
      && EDGE_COUNT (xbb->succs) == 1
      && (EDGE_SUCC (xbb, 0)->flags & EDGE_FALLTHRU)
      /* When successor is an EXIT block, it may not be the next block.  */
      && single_succ (xbb) != EXIT_BLOCK_PTR_FOR_FN (cfun)
      /* And unconditional jump in previous basic block leads to
         next basic block of XBB and this jump can be safely removed.  */
      && in_current_region_p (xbb->prev_bb)
      && bb_has_removable_jump_to_p (xbb->prev_bb, xbb->next_bb)
      && INSN_SCHED_TIMES (BB_END (xbb->prev_bb)) == 0
      /* Also this jump is not at the scheduling boundary.  */
      && !IN_CURRENT_FENCE_P (BB_END (xbb->prev_bb)))
    {
      bool recompute_toporder_p;
      /* Clear data structures of jump - jump itself will be removed
         by sel_redirect_edge_and_branch.  */
      clear_expr (INSN_EXPR (BB_END (xbb->prev_bb)));
      recompute_toporder_p
        = sel_redirect_edge_and_branch (EDGE_SUCC (xbb->prev_bb, 0), xbb);

      gcc_assert (EDGE_SUCC (xbb->prev_bb, 0)->flags & EDGE_FALLTHRU);

      /* It can turn out that after removing unused jump, basic block
         that contained that jump, becomes empty too.  In such case
         remove it too.  */
      if (sel_bb_empty_p (xbb->prev_bb))
        changed = maybe_tidy_empty_bb (xbb->prev_bb);
      if (recompute_toporder_p)
	sel_recompute_toporder ();
    }

#ifdef ENABLE_CHECKING
  verify_backedges ();
  verify_dominators (CDI_DOMINATORS);
#endif

  return changed;
}

/* Purge meaningless empty blocks in the middle of a region.  */
void
purge_empty_blocks (void)
{
  int i;

  /* Do not attempt to delete the first basic block in the region.  */
  for (i = 1; i < current_nr_blocks; )
    {
      basic_block b = BASIC_BLOCK_FOR_FN (cfun, BB_TO_BLOCK (i));

      if (maybe_tidy_empty_bb (b))
	continue;

      i++;
    }
}

/* Rip-off INSN from the insn stream.  When ONLY_DISCONNECT is true,
   do not delete insn's data, because it will be later re-emitted.
   Return true if we have removed some blocks afterwards.  */
bool
sel_remove_insn (insn_t insn, bool only_disconnect, bool full_tidying)
{
  basic_block bb = BLOCK_FOR_INSN (insn);

  gcc_assert (INSN_IN_STREAM_P (insn));

  if (DEBUG_INSN_P (insn) && BB_AV_SET_VALID_P (bb))
    {
      expr_t expr;
      av_set_iterator i;

      /* When we remove a debug insn that is head of a BB, it remains
	 in the AV_SET of the block, but it shouldn't.  */
      FOR_EACH_EXPR_1 (expr, i, &BB_AV_SET (bb))
	if (EXPR_INSN_RTX (expr) == insn)
	  {
	    av_set_iter_remove (&i);
	    break;
	  }
    }

  if (only_disconnect)
    remove_insn (insn);
  else
    {
      delete_insn (insn);
      clear_expr (INSN_EXPR (insn));
    }

  /* It is necessary to NULL these fields in case we are going to re-insert
     INSN into the insns stream, as will usually happen in the ONLY_DISCONNECT
     case, but also for NOPs that we will return to the nop pool.  */
  PREV_INSN (insn) = NULL_RTX;
  NEXT_INSN (insn) = NULL_RTX;
  set_block_for_insn (insn, NULL);

  return tidy_control_flow (bb, full_tidying);
}

/* Estimate number of the insns in BB.  */
static int
sel_estimate_number_of_insns (basic_block bb)
{
  int res = 0;
  insn_t insn = NEXT_INSN (BB_HEAD (bb)), next_tail = NEXT_INSN (BB_END (bb));

  for (; insn != next_tail; insn = NEXT_INSN (insn))
    if (NONDEBUG_INSN_P (insn))
      res++;

  return res;
}

/* We don't need separate luids for notes or labels.  */
static int
sel_luid_for_non_insn (rtx x)
{
  gcc_assert (NOTE_P (x) || LABEL_P (x));

  return -1;
}

/*  Find the proper seqno for inserting at INSN by successors.
    Return -1 if no successors with positive seqno exist.  */
static int
get_seqno_by_succs (rtx insn)
{
  basic_block bb = BLOCK_FOR_INSN (insn);
  rtx tmp = insn, end = BB_END (bb);
  int seqno;
  insn_t succ = NULL;
  succ_iterator si;

  while (tmp != end)
    {
      tmp = NEXT_INSN (tmp);
      if (INSN_P (tmp))
        return INSN_SEQNO (tmp);
    }

  seqno = INT_MAX;

  FOR_EACH_SUCC_1 (succ, si, end, SUCCS_NORMAL)
    if (INSN_SEQNO (succ) > 0)
      seqno = MIN (seqno, INSN_SEQNO (succ));

  if (seqno == INT_MAX)
    return -1;

  return seqno;
}

/* Compute seqno for INSN by its preds or succs.  Use OLD_SEQNO to compute
   seqno in corner cases.  */
static int
get_seqno_for_a_jump (insn_t insn, int old_seqno)
{
  int seqno;

  gcc_assert (INSN_SIMPLEJUMP_P (insn));

  if (!sel_bb_head_p (insn))
    seqno = INSN_SEQNO (PREV_INSN (insn));
  else
    {
      basic_block bb = BLOCK_FOR_INSN (insn);

      if (single_pred_p (bb)
	  && !in_current_region_p (single_pred (bb)))
	{
          /* We can have preds outside a region when splitting edges
             for pipelining of an outer loop.  Use succ instead.
             There should be only one of them.  */
	  insn_t succ = NULL;
          succ_iterator si;
          bool first = true;

	  gcc_assert (flag_sel_sched_pipelining_outer_loops
		      && current_loop_nest);
          FOR_EACH_SUCC_1 (succ, si, insn,
                           SUCCS_NORMAL | SUCCS_SKIP_TO_LOOP_EXITS)
            {
              gcc_assert (first);
              first = false;
            }

	  gcc_assert (succ != NULL);
	  seqno = INSN_SEQNO (succ);
	}
      else
	{
	  insn_t *preds;
	  int n;

	  cfg_preds (BLOCK_FOR_INSN (insn), &preds, &n);

	  gcc_assert (n > 0);
	  /* For one predecessor, use simple method.  */
	  if (n == 1)
	    seqno = INSN_SEQNO (preds[0]);
	  else
	    seqno = get_seqno_by_preds (insn);

	  free (preds);
	}
    }

  /* We were unable to find a good seqno among preds.  */
  if (seqno < 0)
    seqno = get_seqno_by_succs (insn);

  if (seqno < 0)
    {
      /* The only case where this could be here legally is that the only
	 unscheduled insn was a conditional jump that got removed and turned
	 into this unconditional one.  Initialize from the old seqno
	 of that jump passed down to here.  */
      seqno = old_seqno;
    }

  gcc_assert (seqno >= 0);
  return seqno;
}

/*  Find the proper seqno for inserting at INSN.  Returns -1 if no predecessors
    with positive seqno exist.  */
int
get_seqno_by_preds (rtx insn)
{
  basic_block bb = BLOCK_FOR_INSN (insn);
  rtx tmp = insn, head = BB_HEAD (bb);
  insn_t *preds;
  int n, i, seqno;

  while (tmp != head)
    {
      tmp = PREV_INSN (tmp);
      if (INSN_P (tmp))
        return INSN_SEQNO (tmp);
    }

  cfg_preds (bb, &preds, &n);
  for (i = 0, seqno = -1; i < n; i++)
    seqno = MAX (seqno, INSN_SEQNO (preds[i]));

  return seqno;
}



/* Extend pass-scope data structures for basic blocks.  */
void
sel_extend_global_bb_info (void)
{
  sel_global_bb_info.safe_grow_cleared (last_basic_block_for_fn (cfun));
}

/* Extend region-scope data structures for basic blocks.  */
static void
extend_region_bb_info (void)
{
  sel_region_bb_info.safe_grow_cleared (last_basic_block_for_fn (cfun));
}

/* Extend all data structures to fit for all basic blocks.  */
static void
extend_bb_info (void)
{
  sel_extend_global_bb_info ();
  extend_region_bb_info ();
}

/* Finalize pass-scope data structures for basic blocks.  */
void
sel_finish_global_bb_info (void)
{
  sel_global_bb_info.release ();
}

/* Finalize region-scope data structures for basic blocks.  */
static void
finish_region_bb_info (void)
{
  sel_region_bb_info.release ();
}


/* Data for each insn in current region.  */
vec<sel_insn_data_def> s_i_d = vNULL;

/* Extend data structures for insns from current region.  */
static void
extend_insn_data (void)
{
  int reserve;

  sched_extend_target ();
  sched_deps_init (false);

  /* Extend data structures for insns from current region.  */
  reserve = (sched_max_luid + 1 - s_i_d.length ());
  if (reserve > 0 && ! s_i_d.space (reserve))
    {
      int size;

      if (sched_max_luid / 2 > 1024)
        size = sched_max_luid + 1024;
      else
        size = 3 * sched_max_luid / 2;


      s_i_d.safe_grow_cleared (size);
    }
}

/* Finalize data structures for insns from current region.  */
static void
finish_insns (void)
{
  unsigned i;

  /* Clear here all dependence contexts that may have left from insns that were
     removed during the scheduling.  */
  for (i = 0; i < s_i_d.length (); i++)
    {
      sel_insn_data_def *sid_entry = &s_i_d[i];

      if (sid_entry->live)
        return_regset_to_pool (sid_entry->live);
      if (sid_entry->analyzed_deps)
	{
	  BITMAP_FREE (sid_entry->analyzed_deps);
	  BITMAP_FREE (sid_entry->found_deps);
          htab_delete (sid_entry->transformed_insns);
	  free_deps (&sid_entry->deps_context);
	}
      if (EXPR_VINSN (&sid_entry->expr))
        {
          clear_expr (&sid_entry->expr);

          /* Also, clear CANT_MOVE bit here, because we really don't want it
             to be passed to the next region.  */
          CANT_MOVE_BY_LUID (i) = 0;
        }
    }

  s_i_d.release ();
}

/* A proxy to pass initialization data to init_insn ().  */
static sel_insn_data_def _insn_init_ssid;
static sel_insn_data_t insn_init_ssid = &_insn_init_ssid;

/* If true create a new vinsn.  Otherwise use the one from EXPR.  */
static bool insn_init_create_new_vinsn_p;

/* Set all necessary data for initialization of the new insn[s].  */
static expr_t
set_insn_init (expr_t expr, vinsn_t vi, int seqno)
{
  expr_t x = &insn_init_ssid->expr;

  copy_expr_onside (x, expr);
  if (vi != NULL)
    {
      insn_init_create_new_vinsn_p = false;
      change_vinsn_in_expr (x, vi);
    }
  else
    insn_init_create_new_vinsn_p = true;

  insn_init_ssid->seqno = seqno;
  return x;
}

/* Init data for INSN.  */
static void
init_insn_data (insn_t insn)
{
  expr_t expr;
  sel_insn_data_t ssid = insn_init_ssid;

  /* The fields mentioned below are special and hence are not being
     propagated to the new insns.  */
  gcc_assert (!ssid->asm_p && ssid->sched_next == NULL
	      && !ssid->after_stall_p && ssid->sched_cycle == 0);
  gcc_assert (INSN_P (insn) && INSN_LUID (insn) > 0);

  expr = INSN_EXPR (insn);
  copy_expr (expr, &ssid->expr);
  prepare_insn_expr (insn, ssid->seqno);

  if (insn_init_create_new_vinsn_p)
    change_vinsn_in_expr (expr, vinsn_create (insn, init_insn_force_unique_p));

  if (first_time_insn_init (insn))
    init_first_time_insn_data (insn);
}

/* This is used to initialize spurious jumps generated by
   sel_redirect_edge ().  OLD_SEQNO is used for initializing seqnos
   in corner cases within get_seqno_for_a_jump.  */
static void
init_simplejump_data (insn_t insn, int old_seqno)
{
  init_expr (INSN_EXPR (insn), vinsn_create (insn, false), 0,
	     REG_BR_PROB_BASE, 0, 0, 0, 0, 0, 0,
	     vNULL, true, false, false,
	     false, true);
  INSN_SEQNO (insn) = get_seqno_for_a_jump (insn, old_seqno);
  init_first_time_insn_data (insn);
}

/* Perform deferred initialization of insns.  This is used to process
   a new jump that may be created by redirect_edge.  OLD_SEQNO is used
   for initializing simplejumps in init_simplejump_data.  */
static void
sel_init_new_insn (insn_t insn, int flags, int old_seqno)
{
  /* We create data structures for bb when the first insn is emitted in it.  */
  if (INSN_P (insn)
      && INSN_IN_STREAM_P (insn)
      && insn_is_the_only_one_in_bb_p (insn))
    {
      extend_bb_info ();
      create_initial_data_sets (BLOCK_FOR_INSN (insn));
    }

  if (flags & INSN_INIT_TODO_LUID)
    {
      sched_extend_luids ();
      sched_init_insn_luid (insn);
    }

  if (flags & INSN_INIT_TODO_SSID)
    {
      extend_insn_data ();
      init_insn_data (insn);
      clear_expr (&insn_init_ssid->expr);
    }

  if (flags & INSN_INIT_TODO_SIMPLEJUMP)
    {
      extend_insn_data ();
      init_simplejump_data (insn, old_seqno);
    }

  gcc_assert (CONTAINING_RGN (BLOCK_NUM (insn))
              == CONTAINING_RGN (BB_TO_BLOCK (0)));
}


/* Functions to init/finish work with lv sets.  */

/* Init BB_LV_SET of BB from DF_LR_IN set of BB.  */
static void
init_lv_set (basic_block bb)
{
  gcc_assert (!BB_LV_SET_VALID_P (bb));

  BB_LV_SET (bb) = get_regset_from_pool ();
  COPY_REG_SET (BB_LV_SET (bb), DF_LR_IN (bb));
  BB_LV_SET_VALID_P (bb) = true;
}

/* Copy liveness information to BB from FROM_BB.  */
static void
copy_lv_set_from (basic_block bb, basic_block from_bb)
{
  gcc_assert (!BB_LV_SET_VALID_P (bb));

  COPY_REG_SET (BB_LV_SET (bb), BB_LV_SET (from_bb));
  BB_LV_SET_VALID_P (bb) = true;
}

/* Initialize lv set of all bb headers.  */
void
init_lv_sets (void)
{
  basic_block bb;

  /* Initialize of LV sets.  */
  FOR_EACH_BB_FN (bb, cfun)
    init_lv_set (bb);

  /* Don't forget EXIT_BLOCK.  */
  init_lv_set (EXIT_BLOCK_PTR_FOR_FN (cfun));
}

/* Release lv set of HEAD.  */
static void
free_lv_set (basic_block bb)
{
  gcc_assert (BB_LV_SET (bb) != NULL);

  return_regset_to_pool (BB_LV_SET (bb));
  BB_LV_SET (bb) = NULL;
  BB_LV_SET_VALID_P (bb) = false;
}

/* Finalize lv sets of all bb headers.  */
void
free_lv_sets (void)
{
  basic_block bb;

  /* Don't forget EXIT_BLOCK.  */
  free_lv_set (EXIT_BLOCK_PTR_FOR_FN (cfun));

  /* Free LV sets.  */
  FOR_EACH_BB_FN (bb, cfun)
    if (BB_LV_SET (bb))
      free_lv_set (bb);
}

/* Mark AV_SET for BB as invalid, so this set will be updated the next time
   compute_av() processes BB.  This function is called when creating new basic
   blocks, as well as for blocks (either new or existing) where new jumps are
   created when the control flow is being updated.  */
static void
invalidate_av_set (basic_block bb)
{
  BB_AV_LEVEL (bb) = -1;
}

/* Create initial data sets for BB (they will be invalid).  */
static void
create_initial_data_sets (basic_block bb)
{
  if (BB_LV_SET (bb))
    BB_LV_SET_VALID_P (bb) = false;
  else
    BB_LV_SET (bb) = get_regset_from_pool ();
  invalidate_av_set (bb);
}

/* Free av set of BB.  */
static void
free_av_set (basic_block bb)
{
  av_set_clear (&BB_AV_SET (bb));
  BB_AV_LEVEL (bb) = 0;
}

/* Free data sets of BB.  */
void
free_data_sets (basic_block bb)
{
  free_lv_set (bb);
  free_av_set (bb);
}

/* Exchange lv sets of TO and FROM.  */
static void
exchange_lv_sets (basic_block to, basic_block from)
{
  {
    regset to_lv_set = BB_LV_SET (to);

    BB_LV_SET (to) = BB_LV_SET (from);
    BB_LV_SET (from) = to_lv_set;
  }

  {
    bool to_lv_set_valid_p = BB_LV_SET_VALID_P (to);

    BB_LV_SET_VALID_P (to) = BB_LV_SET_VALID_P (from);
    BB_LV_SET_VALID_P (from) = to_lv_set_valid_p;
  }
}


/* Exchange av sets of TO and FROM.  */
static void
exchange_av_sets (basic_block to, basic_block from)
{
  {
    av_set_t to_av_set = BB_AV_SET (to);

    BB_AV_SET (to) = BB_AV_SET (from);
    BB_AV_SET (from) = to_av_set;
  }

  {
    int to_av_level = BB_AV_LEVEL (to);

    BB_AV_LEVEL (to) = BB_AV_LEVEL (from);
    BB_AV_LEVEL (from) = to_av_level;
  }
}

/* Exchange data sets of TO and FROM.  */
void
exchange_data_sets (basic_block to, basic_block from)
{
  exchange_lv_sets (to, from);
  exchange_av_sets (to, from);
}

/* Copy data sets of FROM to TO.  */
void
copy_data_sets (basic_block to, basic_block from)
{
  gcc_assert (!BB_LV_SET_VALID_P (to) && !BB_AV_SET_VALID_P (to));
  gcc_assert (BB_AV_SET (to) == NULL);

  BB_AV_LEVEL (to) = BB_AV_LEVEL (from);
  BB_LV_SET_VALID_P (to) = BB_LV_SET_VALID_P (from);

  if (BB_AV_SET_VALID_P (from))
    {
      BB_AV_SET (to) = av_set_copy (BB_AV_SET (from));
    }
  if (BB_LV_SET_VALID_P (from))
    {
      gcc_assert (BB_LV_SET (to) != NULL);
      COPY_REG_SET (BB_LV_SET (to), BB_LV_SET (from));
    }
}

/* Return an av set for INSN, if any.  */
av_set_t
get_av_set (insn_t insn)
{
  av_set_t av_set;

  gcc_assert (AV_SET_VALID_P (insn));

  if (sel_bb_head_p (insn))
    av_set = BB_AV_SET (BLOCK_FOR_INSN (insn));
  else
    av_set = NULL;

  return av_set;
}

/* Implementation of AV_LEVEL () macro.  Return AV_LEVEL () of INSN.  */
int
get_av_level (insn_t insn)
{
  int av_level;

  gcc_assert (INSN_P (insn));

  if (sel_bb_head_p (insn))
    av_level = BB_AV_LEVEL (BLOCK_FOR_INSN (insn));
  else
    av_level = INSN_WS_LEVEL (insn);

  return av_level;
}



/* Variables to work with control-flow graph.  */

/* The basic block that already has been processed by the sched_data_update (),
   but hasn't been in sel_add_bb () yet.  */
static vec<basic_block>
    last_added_blocks = vNULL;

/* A pool for allocating successor infos.  */
static struct
{
  /* A stack for saving succs_info structures.  */
  struct succs_info *stack;

  /* Its size.  */
  int size;

  /* Top of the stack.  */
  int top;

  /* Maximal value of the top.  */
  int max_top;
}  succs_info_pool;

/* Functions to work with control-flow graph.  */

/* Return basic block note of BB.  */
insn_t
sel_bb_head (basic_block bb)
{
  insn_t head;

  if (bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
    {
      gcc_assert (exit_insn != NULL_RTX);
      head = exit_insn;
    }
  else
    {
      insn_t note;

      note = bb_note (bb);
      head = next_nonnote_insn (note);

      if (head && (BARRIER_P (head) || BLOCK_FOR_INSN (head) != bb))
	head = NULL_RTX;
    }

  return head;
}

/* Return true if INSN is a basic block header.  */
bool
sel_bb_head_p (insn_t insn)
{
  return sel_bb_head (BLOCK_FOR_INSN (insn)) == insn;
}

/* Return last insn of BB.  */
insn_t
sel_bb_end (basic_block bb)
{
  if (sel_bb_empty_p (bb))
    return NULL_RTX;

  gcc_assert (bb != EXIT_BLOCK_PTR_FOR_FN (cfun));

  return BB_END (bb);
}

/* Return true if INSN is the last insn in its basic block.  */
bool
sel_bb_end_p (insn_t insn)
{
  return insn == sel_bb_end (BLOCK_FOR_INSN (insn));
}

/* Return true if BB consist of single NOTE_INSN_BASIC_BLOCK.  */
bool
sel_bb_empty_p (basic_block bb)
{
  return sel_bb_head (bb) == NULL;
}

/* True when BB belongs to the current scheduling region.  */
bool
in_current_region_p (basic_block bb)
{
  if (bb->index < NUM_FIXED_BLOCKS)
    return false;

  return CONTAINING_RGN (bb->index) == CONTAINING_RGN (BB_TO_BLOCK (0));
}

/* Return the block which is a fallthru bb of a conditional jump JUMP.  */
basic_block
fallthru_bb_of_jump (rtx jump)
{
  if (!JUMP_P (jump))
    return NULL;

  if (!any_condjump_p (jump))
    return NULL;

  /* A basic block that ends with a conditional jump may still have one successor
     (and be followed by a barrier), we are not interested.  */
  if (single_succ_p (BLOCK_FOR_INSN (jump)))
    return NULL;

  return FALLTHRU_EDGE (BLOCK_FOR_INSN (jump))->dest;
}

/* Remove all notes from BB.  */
static void
init_bb (basic_block bb)
{
  remove_notes (bb_note (bb), BB_END (bb));
  BB_NOTE_LIST (bb) = note_list;
}

void
sel_init_bbs (bb_vec_t bbs)
{
  const struct sched_scan_info_def ssi =
    {
      extend_bb_info, /* extend_bb */
      init_bb, /* init_bb */
      NULL, /* extend_insn */
      NULL /* init_insn */
    };

  sched_scan (&ssi, bbs);
}

/* Restore notes for the whole region.  */
static void
sel_restore_notes (void)
{
  int bb;
  insn_t insn;

  for (bb = 0; bb < current_nr_blocks; bb++)
    {
      basic_block first, last;

      first = EBB_FIRST_BB (bb);
      last = EBB_LAST_BB (bb)->next_bb;

      do
	{
	  note_list = BB_NOTE_LIST (first);
	  restore_other_notes (NULL, first);
	  BB_NOTE_LIST (first) = NULL_RTX;

	  FOR_BB_INSNS (first, insn)
	    if (NONDEBUG_INSN_P (insn))
	      reemit_notes (insn);

          first = first->next_bb;
	}
      while (first != last);
    }
}

/* Free per-bb data structures.  */
void
sel_finish_bbs (void)
{
  sel_restore_notes ();

  /* Remove current loop preheader from this loop.  */
  if (current_loop_nest)
    sel_remove_loop_preheader ();

  finish_region_bb_info ();
}

/* Return true if INSN has a single successor of type FLAGS.  */
bool
sel_insn_has_single_succ_p (insn_t insn, int flags)
{
  insn_t succ;
  succ_iterator si;
  bool first_p = true;

  FOR_EACH_SUCC_1 (succ, si, insn, flags)
    {
      if (first_p)
	first_p = false;
      else
	return false;
    }

  return true;
}

/* Allocate successor's info.  */
static struct succs_info *
alloc_succs_info (void)
{
  if (succs_info_pool.top == succs_info_pool.max_top)
    {
      int i;

      if (++succs_info_pool.max_top >= succs_info_pool.size)
        gcc_unreachable ();

      i = ++succs_info_pool.top;
      succs_info_pool.stack[i].succs_ok.create (10);
      succs_info_pool.stack[i].succs_other.create (10);
      succs_info_pool.stack[i].probs_ok.create (10);
    }
  else
    succs_info_pool.top++;

  return &succs_info_pool.stack[succs_info_pool.top];
}

/* Free successor's info.  */
void
free_succs_info (struct succs_info * sinfo)
{
  gcc_assert (succs_info_pool.top >= 0
              && &succs_info_pool.stack[succs_info_pool.top] == sinfo);
  succs_info_pool.top--;

  /* Clear stale info.  */
  sinfo->succs_ok.block_remove (0, sinfo->succs_ok.length ());
  sinfo->succs_other.block_remove (0, sinfo->succs_other.length ());
  sinfo->probs_ok.block_remove (0, sinfo->probs_ok.length ());
  sinfo->all_prob = 0;
  sinfo->succs_ok_n = 0;
  sinfo->all_succs_n = 0;
}

/* Compute successor info for INSN.  FLAGS are the flags passed
   to the FOR_EACH_SUCC_1 iterator.  */
struct succs_info *
compute_succs_info (insn_t insn, short flags)
{
  succ_iterator si;
  insn_t succ;
  struct succs_info *sinfo = alloc_succs_info ();

  /* Traverse *all* successors and decide what to do with each.  */
  FOR_EACH_SUCC_1 (succ, si, insn, SUCCS_ALL)
    {
      /* FIXME: this doesn't work for skipping to loop exits, as we don't
         perform code motion through inner loops.  */
      short current_flags = si.current_flags & ~SUCCS_SKIP_TO_LOOP_EXITS;

      if (current_flags & flags)
        {
          sinfo->succs_ok.safe_push (succ);
          sinfo->probs_ok.safe_push (
		    /* FIXME: Improve calculation when skipping
                       inner loop to exits.  */
                    si.bb_end ? si.e1->probability : REG_BR_PROB_BASE);
          sinfo->succs_ok_n++;
        }
      else
        sinfo->succs_other.safe_push (succ);

      /* Compute all_prob.  */
      if (!si.bb_end)
        sinfo->all_prob = REG_BR_PROB_BASE;
      else
        sinfo->all_prob += si.e1->probability;

      sinfo->all_succs_n++;
    }

  return sinfo;
}

/* Return the predecessors of BB in PREDS and their number in N.
   Empty blocks are skipped.  SIZE is used to allocate PREDS.  */
static void
cfg_preds_1 (basic_block bb, insn_t **preds, int *n, int *size)
{
  edge e;
  edge_iterator ei;

  gcc_assert (BLOCK_TO_BB (bb->index) != 0);

  FOR_EACH_EDGE (e, ei, bb->preds)
    {
      basic_block pred_bb = e->src;
      insn_t bb_end = BB_END (pred_bb);

      if (!in_current_region_p (pred_bb))
	{
	  gcc_assert (flag_sel_sched_pipelining_outer_loops
		      && current_loop_nest);
	  continue;
	}

      if (sel_bb_empty_p (pred_bb))
	cfg_preds_1 (pred_bb, preds, n, size);
      else
	{
	  if (*n == *size)
	    *preds = XRESIZEVEC (insn_t, *preds,
                                 (*size = 2 * *size + 1));
	  (*preds)[(*n)++] = bb_end;
	}
    }

  gcc_assert (*n != 0
	      || (flag_sel_sched_pipelining_outer_loops
		  && current_loop_nest));
}

/* Find all predecessors of BB and record them in PREDS and their number
   in N.  Empty blocks are skipped, and only normal (forward in-region)
   edges are processed.  */
static void
cfg_preds (basic_block bb, insn_t **preds, int *n)
{
  int size = 0;

  *preds = NULL;
  *n = 0;
  cfg_preds_1 (bb, preds, n, &size);
}

/* Returns true if we are moving INSN through join point.  */
bool
sel_num_cfg_preds_gt_1 (insn_t insn)
{
  basic_block bb;

  if (!sel_bb_head_p (insn) || INSN_BB (insn) == 0)
    return false;

  bb = BLOCK_FOR_INSN (insn);

  while (1)
    {
      if (EDGE_COUNT (bb->preds) > 1)
	return true;

      gcc_assert (EDGE_PRED (bb, 0)->dest == bb);
      bb = EDGE_PRED (bb, 0)->src;

      if (!sel_bb_empty_p (bb))
	break;
    }

  return false;
}

/* Returns true when BB should be the end of an ebb.  Adapted from the
   code in sched-ebb.c.  */
bool
bb_ends_ebb_p (basic_block bb)
{
  basic_block next_bb = bb_next_bb (bb);
  edge e;

  if (next_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)
      || bitmap_bit_p (forced_ebb_heads, next_bb->index)
      || (LABEL_P (BB_HEAD (next_bb))
	  /* NB: LABEL_NUSES () is not maintained outside of jump.c.
	     Work around that.  */
	  && !single_pred_p (next_bb)))
    return true;

  if (!in_current_region_p (next_bb))
    return true;

  e = find_fallthru_edge (bb->succs);
  if (e)
    {
      gcc_assert (e->dest == next_bb);
      
      return false;
    }

  return true;
}

/* Returns true when INSN and SUCC are in the same EBB, given that SUCC is a
   successor of INSN.  */
bool
in_same_ebb_p (insn_t insn, insn_t succ)
{
  basic_block ptr = BLOCK_FOR_INSN (insn);

  for (;;)
    {
      if (ptr == BLOCK_FOR_INSN (succ))
        return true;

      if (bb_ends_ebb_p (ptr))
        return false;

      ptr = bb_next_bb (ptr);
    }

  gcc_unreachable ();
  return false;
}

/* Recomputes the reverse topological order for the function and
   saves it in REV_TOP_ORDER_INDEX.  REV_TOP_ORDER_INDEX_LEN is also
   modified appropriately.  */
static void
recompute_rev_top_order (void)
{
  int *postorder;
  int n_blocks, i;

  if (!rev_top_order_index
      || rev_top_order_index_len < last_basic_block_for_fn (cfun))
    {
      rev_top_order_index_len = last_basic_block_for_fn (cfun);
      rev_top_order_index = XRESIZEVEC (int, rev_top_order_index,
                                        rev_top_order_index_len);
    }

  postorder = XNEWVEC (int, n_basic_blocks_for_fn (cfun));

  n_blocks = post_order_compute (postorder, true, false);
  gcc_assert (n_basic_blocks_for_fn (cfun) == n_blocks);

  /* Build reverse function: for each basic block with BB->INDEX == K
     rev_top_order_index[K] is it's reverse topological sort number.  */
  for (i = 0; i < n_blocks; i++)
    {
      gcc_assert (postorder[i] < rev_top_order_index_len);
      rev_top_order_index[postorder[i]] = i;
    }

  free (postorder);
}

/* Clear all flags from insns in BB that could spoil its rescheduling.  */
void
clear_outdated_rtx_info (basic_block bb)
{
  rtx insn;

  FOR_BB_INSNS (bb, insn)
    if (INSN_P (insn))
      {
	SCHED_GROUP_P (insn) = 0;
	INSN_AFTER_STALL_P (insn) = 0;
	INSN_SCHED_TIMES (insn) = 0;
	EXPR_PRIORITY_ADJ (INSN_EXPR (insn)) = 0;

        /* We cannot use the changed caches, as previously we could ignore
           the LHS dependence due to enabled renaming and transform
           the expression, and currently we'll be unable to do this.  */
        htab_empty (INSN_TRANSFORMED_INSNS (insn));
      }
}

/* Add BB_NOTE to the pool of available basic block notes.  */
static void
return_bb_to_pool (basic_block bb)
{
  rtx note = bb_note (bb);

  gcc_assert (NOTE_BASIC_BLOCK (note) == bb
	      && bb->aux == NULL);

  /* It turns out that current cfg infrastructure does not support
     reuse of basic blocks.  Don't bother for now.  */
  /*bb_note_pool.safe_push (note);*/
}

/* Get a bb_note from pool or return NULL_RTX if pool is empty.  */
static rtx
get_bb_note_from_pool (void)
{
  if (bb_note_pool.is_empty ())
    return NULL_RTX;
  else
    {
      rtx note = bb_note_pool.pop ();

      PREV_INSN (note) = NULL_RTX;
      NEXT_INSN (note) = NULL_RTX;

      return note;
    }
}

/* Free bb_note_pool.  */
void
free_bb_note_pool (void)
{
  bb_note_pool.release ();
}

/* Setup scheduler pool and successor structure.  */
void
alloc_sched_pools (void)
{
  int succs_size;

  succs_size = MAX_WS + 1;
  succs_info_pool.stack = XCNEWVEC (struct succs_info, succs_size);
  succs_info_pool.size = succs_size;
  succs_info_pool.top = -1;
  succs_info_pool.max_top = -1;

  sched_lists_pool = create_alloc_pool ("sel-sched-lists",
                                        sizeof (struct _list_node), 500);
}

/* Free the pools.  */
void
free_sched_pools (void)
{
  int i;

  free_alloc_pool (sched_lists_pool);
  gcc_assert (succs_info_pool.top == -1);
  for (i = 0; i <= succs_info_pool.max_top; i++)
    {
      succs_info_pool.stack[i].succs_ok.release ();
      succs_info_pool.stack[i].succs_other.release ();
      succs_info_pool.stack[i].probs_ok.release ();
    }
  free (succs_info_pool.stack);
}


/* Returns a position in RGN where BB can be inserted retaining
   topological order.  */
static int
find_place_to_insert_bb (basic_block bb, int rgn)
{
  bool has_preds_outside_rgn = false;
  edge e;
  edge_iterator ei;

  /* Find whether we have preds outside the region.  */
  FOR_EACH_EDGE (e, ei, bb->preds)
    if (!in_current_region_p (e->src))
      {
        has_preds_outside_rgn = true;
        break;
      }

  /* Recompute the top order -- needed when we have > 1 pred
     and in case we don't have preds outside.  */
  if (flag_sel_sched_pipelining_outer_loops
      && (has_preds_outside_rgn || EDGE_COUNT (bb->preds) > 1))
    {
      int i, bbi = bb->index, cur_bbi;

      recompute_rev_top_order ();
      for (i = RGN_NR_BLOCKS (rgn) - 1; i >= 0; i--)
        {
          cur_bbi = BB_TO_BLOCK (i);
          if (rev_top_order_index[bbi]
              < rev_top_order_index[cur_bbi])
            break;
        }

      /* We skipped the right block, so we increase i.  We accommodate
         it for increasing by step later, so we decrease i.  */
      return (i + 1) - 1;
    }
  else if (has_preds_outside_rgn)
    {
      /* This is the case when we generate an extra empty block
         to serve as region head during pipelining.  */
      e = EDGE_SUCC (bb, 0);
      gcc_assert (EDGE_COUNT (bb->succs) == 1
                  && in_current_region_p (EDGE_SUCC (bb, 0)->dest)
                  && (BLOCK_TO_BB (e->dest->index) == 0));
      return -1;
    }

  /* We don't have preds outside the region.  We should have
     the only pred, because the multiple preds case comes from
     the pipelining of outer loops, and that is handled above.
     Just take the bbi of this single pred.  */
  if (EDGE_COUNT (bb->succs) > 0)
    {
      int pred_bbi;

      gcc_assert (EDGE_COUNT (bb->preds) == 1);

      pred_bbi = EDGE_PRED (bb, 0)->src->index;
      return BLOCK_TO_BB (pred_bbi);
    }
  else
    /* BB has no successors.  It is safe to put it in the end.  */
    return current_nr_blocks - 1;
}

/* Deletes an empty basic block freeing its data.  */
static void
delete_and_free_basic_block (basic_block bb)
{
  gcc_assert (sel_bb_empty_p (bb));

  if (BB_LV_SET (bb))
    free_lv_set (bb);

  bitmap_clear_bit (blocks_to_reschedule, bb->index);

  /* Can't assert av_set properties because we use sel_aremove_bb
     when removing loop preheader from the region.  At the point of
     removing the preheader we already have deallocated sel_region_bb_info.  */
  gcc_assert (BB_LV_SET (bb) == NULL
              && !BB_LV_SET_VALID_P (bb)
              && BB_AV_LEVEL (bb) == 0
              && BB_AV_SET (bb) == NULL);

  delete_basic_block (bb);
}

/* Add BB to the current region and update the region data.  */
static void
add_block_to_current_region (basic_block bb)
{
  int i, pos, bbi = -2, rgn;

  rgn = CONTAINING_RGN (BB_TO_BLOCK (0));
  bbi = find_place_to_insert_bb (bb, rgn);
  bbi += 1;
  pos = RGN_BLOCKS (rgn) + bbi;

  gcc_assert (RGN_HAS_REAL_EBB (rgn) == 0
              && ebb_head[bbi] == pos);

  /* Make a place for the new block.  */
  extend_regions ();

  for (i = RGN_BLOCKS (rgn + 1) - 1; i >= pos; i--)
    BLOCK_TO_BB (rgn_bb_table[i])++;

  memmove (rgn_bb_table + pos + 1,
           rgn_bb_table + pos,
           (RGN_BLOCKS (nr_regions) - pos) * sizeof (*rgn_bb_table));

  /* Initialize data for BB.  */
  rgn_bb_table[pos] = bb->index;
  BLOCK_TO_BB (bb->index) = bbi;
  CONTAINING_RGN (bb->index) = rgn;

  RGN_NR_BLOCKS (rgn)++;

  for (i = rgn + 1; i <= nr_regions; i++)
    RGN_BLOCKS (i)++;
}

/* Remove BB from the current region and update the region data.  */
static void
remove_bb_from_region (basic_block bb)
{
  int i, pos, bbi = -2, rgn;

  rgn = CONTAINING_RGN (BB_TO_BLOCK (0));
  bbi = BLOCK_TO_BB (bb->index);
  pos = RGN_BLOCKS (rgn) + bbi;

  gcc_assert (RGN_HAS_REAL_EBB (rgn) == 0
              && ebb_head[bbi] == pos);

  for (i = RGN_BLOCKS (rgn + 1) - 1; i >= pos; i--)
    BLOCK_TO_BB (rgn_bb_table[i])--;

  memmove (rgn_bb_table + pos,
           rgn_bb_table + pos + 1,
           (RGN_BLOCKS (nr_regions) - pos) * sizeof (*rgn_bb_table));

  RGN_NR_BLOCKS (rgn)--;
  for (i = rgn + 1; i <= nr_regions; i++)
    RGN_BLOCKS (i)--;
}

/* Add BB to the current region  and update all data.  If BB is NULL, add all
   blocks from last_added_blocks vector.  */
static void
sel_add_bb (basic_block bb)
{
  /* Extend luids so that new notes will receive zero luids.  */
  sched_extend_luids ();
  sched_init_bbs ();
  sel_init_bbs (last_added_blocks);

  /* When bb is passed explicitly, the vector should contain
     the only element that equals to bb; otherwise, the vector
     should not be NULL.  */
  gcc_assert (last_added_blocks.exists ());

  if (bb != NULL)
    {
      gcc_assert (last_added_blocks.length () == 1
                  && last_added_blocks[0] == bb);
      add_block_to_current_region (bb);

      /* We associate creating/deleting data sets with the first insn
         appearing / disappearing in the bb.  */
      if (!sel_bb_empty_p (bb) && BB_LV_SET (bb) == NULL)
	create_initial_data_sets (bb);

      last_added_blocks.release ();
    }
  else
    /* BB is NULL - process LAST_ADDED_BLOCKS instead.  */
    {
      int i;
      basic_block temp_bb = NULL;

      for (i = 0;
           last_added_blocks.iterate (i, &bb); i++)
        {
          add_block_to_current_region (bb);
          temp_bb = bb;
        }

      /* We need to fetch at least one bb so we know the region
         to update.  */
      gcc_assert (temp_bb != NULL);
      bb = temp_bb;

      last_added_blocks.release ();
    }

  rgn_setup_region (CONTAINING_RGN (bb->index));
}

/* Remove BB from the current region and update all data.
   If REMOVE_FROM_CFG_PBB is true, also remove the block cfom cfg.  */
static void
sel_remove_bb (basic_block bb, bool remove_from_cfg_p)
{
  unsigned idx = bb->index;

  gcc_assert (bb != NULL && BB_NOTE_LIST (bb) == NULL_RTX);

  remove_bb_from_region (bb);
  return_bb_to_pool (bb);
  bitmap_clear_bit (blocks_to_reschedule, idx);

  if (remove_from_cfg_p)
    {
      basic_block succ = single_succ (bb);
      delete_and_free_basic_block (bb);
      set_immediate_dominator (CDI_DOMINATORS, succ,
                               recompute_dominator (CDI_DOMINATORS, succ));
    }

  rgn_setup_region (CONTAINING_RGN (idx));
}

/* Concatenate info of EMPTY_BB to info of MERGE_BB.  */
static void
move_bb_info (basic_block merge_bb, basic_block empty_bb)
{
  if (in_current_region_p (merge_bb))
    concat_note_lists (BB_NOTE_LIST (empty_bb),
		       &BB_NOTE_LIST (merge_bb));
  BB_NOTE_LIST (empty_bb) = NULL_RTX;

}

/* Remove EMPTY_BB.  If REMOVE_FROM_CFG_P is false, remove EMPTY_BB from
   region, but keep it in CFG.  */
static void
remove_empty_bb (basic_block empty_bb, bool remove_from_cfg_p)
{
  /* The block should contain just a note or a label.
     We try to check whether it is unused below.  */
  gcc_assert (BB_HEAD (empty_bb) == BB_END (empty_bb)
              || LABEL_P (BB_HEAD (empty_bb)));

  /* If basic block has predecessors or successors, redirect them.  */
  if (remove_from_cfg_p
      && (EDGE_COUNT (empty_bb->preds) > 0
	  || EDGE_COUNT (empty_bb->succs) > 0))
    {
      basic_block pred;
      basic_block succ;

      /* We need to init PRED and SUCC before redirecting edges.  */
      if (EDGE_COUNT (empty_bb->preds) > 0)
	{
	  edge e;

	  gcc_assert (EDGE_COUNT (empty_bb->preds) == 1);

	  e = EDGE_PRED (empty_bb, 0);
          gcc_assert (e->src == empty_bb->prev_bb
		      && (e->flags & EDGE_FALLTHRU));

	  pred = empty_bb->prev_bb;
	}
      else
	pred = NULL;

      if (EDGE_COUNT (empty_bb->succs) > 0)
	{
          /* We do not check fallthruness here as above, because
             after removing a jump the edge may actually be not fallthru.  */
	  gcc_assert (EDGE_COUNT (empty_bb->succs) == 1);
	  succ = EDGE_SUCC (empty_bb, 0)->dest;
	}
      else
	succ = NULL;

      if (EDGE_COUNT (empty_bb->preds) > 0 && succ != NULL)
        {
          edge e = EDGE_PRED (empty_bb, 0);

          if (e->flags & EDGE_FALLTHRU)
            redirect_edge_succ_nodup (e, succ);
          else
            sel_redirect_edge_and_branch (EDGE_PRED (empty_bb, 0), succ);
        }

      if (EDGE_COUNT (empty_bb->succs) > 0 && pred != NULL)
	{
	  edge e = EDGE_SUCC (empty_bb, 0);

	  if (find_edge (pred, e->dest) == NULL)
	    redirect_edge_pred (e, pred);
	}
    }

  /* Finish removing.  */
  sel_remove_bb (empty_bb, remove_from_cfg_p);
}

/* An implementation of create_basic_block hook, which additionally updates
   per-bb data structures.  */
static basic_block
sel_create_basic_block (void *headp, void *endp, basic_block after)
{
  basic_block new_bb;
  insn_t new_bb_note;

  gcc_assert (flag_sel_sched_pipelining_outer_loops
              || !last_added_blocks.exists ());

  new_bb_note = get_bb_note_from_pool ();

  if (new_bb_note == NULL_RTX)
    new_bb = orig_cfg_hooks.create_basic_block (headp, endp, after);
  else
    {
      new_bb = create_basic_block_structure ((rtx) headp, (rtx) endp,
					     new_bb_note, after);
      new_bb->aux = NULL;
    }

  last_added_blocks.safe_push (new_bb);

  return new_bb;
}

/* Implement sched_init_only_bb ().  */
static void
sel_init_only_bb (basic_block bb, basic_block after)
{
  gcc_assert (after == NULL);

  extend_regions ();
  rgn_make_new_region_out_of_new_block (bb);
}

/* Update the latch when we've splitted or merged it from FROM block to TO.
   This should be checked for all outer loops, too.  */
static void
change_loops_latches (basic_block from, basic_block to)
{
  gcc_assert (from != to);

  if (current_loop_nest)
    {
      struct loop *loop;

      for (loop = current_loop_nest; loop; loop = loop_outer (loop))
        if (considered_for_pipelining_p (loop) && loop->latch == from)
          {
            gcc_assert (loop == current_loop_nest);
            loop->latch = to;
            gcc_assert (loop_latch_edge (loop));
          }
    }
}

/* Splits BB on two basic blocks, adding it to the region and extending
   per-bb data structures.  Returns the newly created bb.  */
static basic_block
sel_split_block (basic_block bb, rtx after)
{
  basic_block new_bb;
  insn_t insn;

  new_bb = sched_split_block_1 (bb, after);
  sel_add_bb (new_bb);

  /* This should be called after sel_add_bb, because this uses
     CONTAINING_RGN for the new block, which is not yet initialized.
     FIXME: this function may be a no-op now.  */
  change_loops_latches (bb, new_bb);

  /* Update ORIG_BB_INDEX for insns moved into the new block.  */
  FOR_BB_INSNS (new_bb, insn)
   if (INSN_P (insn))
     EXPR_ORIG_BB_INDEX (INSN_EXPR (insn)) = new_bb->index;

  if (sel_bb_empty_p (bb))
    {
      gcc_assert (!sel_bb_empty_p (new_bb));

      /* NEW_BB has data sets that need to be updated and BB holds
	 data sets that should be removed.  Exchange these data sets
	 so that we won't lose BB's valid data sets.  */
      exchange_data_sets (new_bb, bb);
      free_data_sets (bb);
    }

  if (!sel_bb_empty_p (new_bb)
      && bitmap_bit_p (blocks_to_reschedule, bb->index))
    bitmap_set_bit (blocks_to_reschedule, new_bb->index);

  return new_bb;
}

/* If BB ends with a jump insn whose ID is bigger then PREV_MAX_UID, return it.
   Otherwise returns NULL.  */
static rtx
check_for_new_jump (basic_block bb, int prev_max_uid)
{
  rtx end;

  end = sel_bb_end (bb);
  if (end && INSN_UID (end) >= prev_max_uid)
    return end;
  return NULL;
}

/* Look for a new jump either in FROM_BB block or in newly created JUMP_BB block.
   New means having UID at least equal to PREV_MAX_UID.  */
static rtx
find_new_jump (basic_block from, basic_block jump_bb, int prev_max_uid)
{
  rtx jump;

  /* Return immediately if no new insns were emitted.  */
  if (get_max_uid () == prev_max_uid)
    return NULL;

  /* Now check both blocks for new jumps.  It will ever be only one.  */
  if ((jump = check_for_new_jump (from, prev_max_uid)))
    return jump;

  if (jump_bb != NULL
      && (jump = check_for_new_jump (jump_bb, prev_max_uid)))
    return jump;
  return NULL;
}

/* Splits E and adds the newly created basic block to the current region.
   Returns this basic block.  */
basic_block
sel_split_edge (edge e)
{
  basic_block new_bb, src, other_bb = NULL;
  int prev_max_uid;
  rtx jump;

  src = e->src;
  prev_max_uid = get_max_uid ();
  new_bb = split_edge (e);

  if (flag_sel_sched_pipelining_outer_loops
      && current_loop_nest)
    {
      int i;
      basic_block bb;

      /* Some of the basic blocks might not have been added to the loop.
         Add them here, until this is fixed in force_fallthru.  */
      for (i = 0;
           last_added_blocks.iterate (i, &bb); i++)
        if (!bb->loop_father)
          {
            add_bb_to_loop (bb, e->dest->loop_father);

            gcc_assert (!other_bb && (new_bb->index != bb->index));
            other_bb = bb;
          }
    }

  /* Add all last_added_blocks to the region.  */
  sel_add_bb (NULL);

  jump = find_new_jump (src, new_bb, prev_max_uid);
  if (jump)
    sel_init_new_insn (jump, INSN_INIT_TODO_LUID | INSN_INIT_TODO_SIMPLEJUMP);

  /* Put the correct lv set on this block.  */
  if (other_bb && !sel_bb_empty_p (other_bb))
    compute_live (sel_bb_head (other_bb));

  return new_bb;
}

/* Implement sched_create_empty_bb ().  */
static basic_block
sel_create_empty_bb (basic_block after)
{
  basic_block new_bb;

  new_bb = sched_create_empty_bb_1 (after);

  /* We'll explicitly initialize NEW_BB via sel_init_only_bb () a bit
     later.  */
  gcc_assert (last_added_blocks.length () == 1
	      && last_added_blocks[0] == new_bb);

  last_added_blocks.release ();
  return new_bb;
}

/* Implement sched_create_recovery_block.  ORIG_INSN is where block
   will be splitted to insert a check.  */
basic_block
sel_create_recovery_block (insn_t orig_insn)
{
  basic_block first_bb, second_bb, recovery_block;
  basic_block before_recovery = NULL;
  rtx jump;

  first_bb = BLOCK_FOR_INSN (orig_insn);
  if (sel_bb_end_p (orig_insn))
    {
      /* Avoid introducing an empty block while splitting.  */
      gcc_assert (single_succ_p (first_bb));
      second_bb = single_succ (first_bb);
    }
  else
    second_bb = sched_split_block (first_bb, orig_insn);

  recovery_block = sched_create_recovery_block (&before_recovery);
  if (before_recovery)
    copy_lv_set_from (before_recovery, EXIT_BLOCK_PTR_FOR_FN (cfun));

  gcc_assert (sel_bb_empty_p (recovery_block));
  sched_create_recovery_edges (first_bb, recovery_block, second_bb);
  if (current_loops != NULL)
    add_bb_to_loop (recovery_block, first_bb->loop_father);

  sel_add_bb (recovery_block);

  jump = BB_END (recovery_block);
  gcc_assert (sel_bb_head (recovery_block) == jump);
  sel_init_new_insn (jump, INSN_INIT_TODO_LUID | INSN_INIT_TODO_SIMPLEJUMP);

  return recovery_block;
}

/* Merge basic block B into basic block A.  */
static void
sel_merge_blocks (basic_block a, basic_block b)
{
  gcc_assert (sel_bb_empty_p (b)
              && EDGE_COUNT (b->preds) == 1
              && EDGE_PRED (b, 0)->src == b->prev_bb);

  move_bb_info (b->prev_bb, b);
  remove_empty_bb (b, false);
  merge_blocks (a, b);
  change_loops_latches (b, a);
}

/* A wrapper for redirect_edge_and_branch_force, which also initializes
   data structures for possibly created bb and insns.  */
void
sel_redirect_edge_and_branch_force (edge e, basic_block to)
{
  basic_block jump_bb, src, orig_dest = e->dest;
  int prev_max_uid;
  rtx jump;
  int old_seqno = -1;

  /* This function is now used only for bookkeeping code creation, where
     we'll never get the single pred of orig_dest block and thus will not
     hit unreachable blocks when updating dominator info.  */
  gcc_assert (!sel_bb_empty_p (e->src)
              && !single_pred_p (orig_dest));
  src = e->src;
  prev_max_uid = get_max_uid ();
  /* Compute and pass old_seqno down to sel_init_new_insn only for the case
     when the conditional jump being redirected may become unconditional.  */
  if (any_condjump_p (BB_END (src))
      && INSN_SEQNO (BB_END (src)) >= 0)
    old_seqno = INSN_SEQNO (BB_END (src));

  jump_bb = redirect_edge_and_branch_force (e, to);
  if (jump_bb != NULL)
    sel_add_bb (jump_bb);

  /* This function could not be used to spoil the loop structure by now,
     thus we don't care to update anything.  But check it to be sure.  */
  if (current_loop_nest
      && pipelining_p)
    gcc_assert (loop_latch_edge (current_loop_nest));

  jump = find_new_jump (src, jump_bb, prev_max_uid);
  if (jump)
    sel_init_new_insn (jump, INSN_INIT_TODO_LUID | INSN_INIT_TODO_SIMPLEJUMP,
		       old_seqno);
  set_immediate_dominator (CDI_DOMINATORS, to,
			   recompute_dominator (CDI_DOMINATORS, to));
  set_immediate_dominator (CDI_DOMINATORS, orig_dest,
			   recompute_dominator (CDI_DOMINATORS, orig_dest));
}

/* A wrapper for redirect_edge_and_branch.  Return TRUE if blocks connected by
   redirected edge are in reverse topological order.  */
bool
sel_redirect_edge_and_branch (edge e, basic_block to)
{
  bool latch_edge_p;
  basic_block src, orig_dest = e->dest;
  int prev_max_uid;
  rtx jump;
  edge redirected;
  bool recompute_toporder_p = false;
  bool maybe_unreachable = single_pred_p (orig_dest);
  int old_seqno = -1;

  latch_edge_p = (pipelining_p
                  && current_loop_nest
                  && e == loop_latch_edge (current_loop_nest));

  src = e->src;
  prev_max_uid = get_max_uid ();

  /* Compute and pass old_seqno down to sel_init_new_insn only for the case
     when the conditional jump being redirected may become unconditional.  */
  if (any_condjump_p (BB_END (src))
      && INSN_SEQNO (BB_END (src)) >= 0)
    old_seqno = INSN_SEQNO (BB_END (src));

  redirected = redirect_edge_and_branch (e, to);

  gcc_assert (redirected && !last_added_blocks.exists ());

  /* When we've redirected a latch edge, update the header.  */
  if (latch_edge_p)
    {
      current_loop_nest->header = to;
      gcc_assert (loop_latch_edge (current_loop_nest));
    }

  /* In rare situations, the topological relation between the blocks connected
     by the redirected edge can change (see PR42245 for an example).  Update
     block_to_bb/bb_to_block.  */
  if (CONTAINING_RGN (e->src->index) == CONTAINING_RGN (to->index)
      && BLOCK_TO_BB (e->src->index) > BLOCK_TO_BB (to->index))
    recompute_toporder_p = true;

  jump = find_new_jump (src, NULL, prev_max_uid);
  if (jump)
    sel_init_new_insn (jump, INSN_INIT_TODO_LUID | INSN_INIT_TODO_SIMPLEJUMP, old_seqno);

  /* Only update dominator info when we don't have unreachable blocks.
     Otherwise we'll update in maybe_tidy_empty_bb.  */
  if (!maybe_unreachable)
    {
      set_immediate_dominator (CDI_DOMINATORS, to,
                               recompute_dominator (CDI_DOMINATORS, to));
      set_immediate_dominator (CDI_DOMINATORS, orig_dest,
                               recompute_dominator (CDI_DOMINATORS, orig_dest));
    }
  return recompute_toporder_p;
}

/* This variable holds the cfg hooks used by the selective scheduler.  */
static struct cfg_hooks sel_cfg_hooks;

/* Register sel-sched cfg hooks.  */
void
sel_register_cfg_hooks (void)
{
  sched_split_block = sel_split_block;

  orig_cfg_hooks = get_cfg_hooks ();
  sel_cfg_hooks = orig_cfg_hooks;

  sel_cfg_hooks.create_basic_block = sel_create_basic_block;

  set_cfg_hooks (sel_cfg_hooks);

  sched_init_only_bb = sel_init_only_bb;
  sched_split_block = sel_split_block;
  sched_create_empty_bb = sel_create_empty_bb;
}

/* Unregister sel-sched cfg hooks.  */
void
sel_unregister_cfg_hooks (void)
{
  sched_create_empty_bb = NULL;
  sched_split_block = NULL;
  sched_init_only_bb = NULL;

  set_cfg_hooks (orig_cfg_hooks);
}


/* Emit an insn rtx based on PATTERN.  If a jump insn is wanted,
   LABEL is where this jump should be directed.  */
rtx
create_insn_rtx_from_pattern (rtx pattern, rtx label)
{
  rtx insn_rtx;

  gcc_assert (!INSN_P (pattern));

  start_sequence ();

  if (label == NULL_RTX)
    insn_rtx = emit_insn (pattern);
  else if (DEBUG_INSN_P (label))
    insn_rtx = emit_debug_insn (pattern);
  else
    {
      insn_rtx = emit_jump_insn (pattern);
      JUMP_LABEL (insn_rtx) = label;
      ++LABEL_NUSES (label);
    }

  end_sequence ();

  sched_extend_luids ();
  sched_extend_target ();
  sched_deps_init (false);

  /* Initialize INSN_CODE now.  */
  recog_memoized (insn_rtx);
  return insn_rtx;
}

/* Create a new vinsn for INSN_RTX.  FORCE_UNIQUE_P is true when the vinsn
   must not be clonable.  */
vinsn_t
create_vinsn_from_insn_rtx (rtx insn_rtx, bool force_unique_p)
{
  gcc_assert (INSN_P (insn_rtx) && !INSN_IN_STREAM_P (insn_rtx));

  /* If VINSN_TYPE is not USE, retain its uniqueness.  */
  return vinsn_create (insn_rtx, force_unique_p);
}

/* Create a copy of INSN_RTX.  */
rtx
create_copy_of_insn_rtx (rtx insn_rtx)
{
  rtx res, link;

  if (DEBUG_INSN_P (insn_rtx))
    return create_insn_rtx_from_pattern (copy_rtx (PATTERN (insn_rtx)),
					 insn_rtx);

  gcc_assert (NONJUMP_INSN_P (insn_rtx));

  res = create_insn_rtx_from_pattern (copy_rtx (PATTERN (insn_rtx)),
                                      NULL_RTX);

  /* Copy all REG_NOTES except REG_EQUAL/REG_EQUIV and REG_LABEL_OPERAND
     since mark_jump_label will make them.  REG_LABEL_TARGETs are created
     there too, but are supposed to be sticky, so we copy them.  */
  for (link = REG_NOTES (insn_rtx); link; link = XEXP (link, 1))
    if (REG_NOTE_KIND (link) != REG_LABEL_OPERAND
	&& REG_NOTE_KIND (link) != REG_EQUAL
	&& REG_NOTE_KIND (link) != REG_EQUIV)
      {
	if (GET_CODE (link) == EXPR_LIST)
	  add_reg_note (res, REG_NOTE_KIND (link),
			copy_insn_1 (XEXP (link, 0)));
	else
	  add_reg_note (res, REG_NOTE_KIND (link), XEXP (link, 0));
      }

  return res;
}

/* Change vinsn field of EXPR to hold NEW_VINSN.  */
void
change_vinsn_in_expr (expr_t expr, vinsn_t new_vinsn)
{
  vinsn_detach (EXPR_VINSN (expr));

  EXPR_VINSN (expr) = new_vinsn;
  vinsn_attach (new_vinsn);
}

/* Helpers for global init.  */
/* This structure is used to be able to call existing bundling mechanism
   and calculate insn priorities.  */
static struct haifa_sched_info sched_sel_haifa_sched_info =
{
  NULL, /* init_ready_list */
  NULL, /* can_schedule_ready_p */
  NULL, /* schedule_more_p */
  NULL, /* new_ready */
  NULL, /* rgn_rank */
  sel_print_insn, /* rgn_print_insn */
  contributes_to_priority,
  NULL, /* insn_finishes_block_p */

  NULL, NULL,
  NULL, NULL,
  0, 0,

  NULL, /* add_remove_insn */
  NULL, /* begin_schedule_ready */
  NULL, /* begin_move_insn */
  NULL, /* advance_target_bb */

  NULL,
  NULL,

  SEL_SCHED | NEW_BBS
};

/* Setup special insns used in the scheduler.  */
void
setup_nop_and_exit_insns (void)
{
  gcc_assert (nop_pattern == NULL_RTX
	      && exit_insn == NULL_RTX);

  nop_pattern = constm1_rtx;

  start_sequence ();
  emit_insn (nop_pattern);
  exit_insn = get_insns ();
  end_sequence ();
  set_block_for_insn (exit_insn, EXIT_BLOCK_PTR_FOR_FN (cfun));
}

/* Free special insns used in the scheduler.  */
void
free_nop_and_exit_insns (void)
{
  exit_insn = NULL_RTX;
  nop_pattern = NULL_RTX;
}

/* Setup a special vinsn used in new insns initialization.  */
void
setup_nop_vinsn (void)
{
  nop_vinsn = vinsn_create (exit_insn, false);
  vinsn_attach (nop_vinsn);
}

/* Free a special vinsn used in new insns initialization.  */
void
free_nop_vinsn (void)
{
  gcc_assert (VINSN_COUNT (nop_vinsn) == 1);
  vinsn_detach (nop_vinsn);
  nop_vinsn = NULL;
}

/* Call a set_sched_flags hook.  */
void
sel_set_sched_flags (void)
{
  /* ??? This means that set_sched_flags were called, and we decided to
     support speculation.  However, set_sched_flags also modifies flags
     on current_sched_info, doing this only at global init.  And we
     sometimes change c_s_i later.  So put the correct flags again.  */
  if (spec_info && targetm.sched.set_sched_flags)
    targetm.sched.set_sched_flags (spec_info);
}

/* Setup pointers to global sched info structures.  */
void
sel_setup_sched_infos (void)
{
  rgn_setup_common_sched_info ();

  memcpy (&sel_common_sched_info, common_sched_info,
	  sizeof (sel_common_sched_info));

  sel_common_sched_info.fix_recovery_cfg = NULL;
  sel_common_sched_info.add_block = NULL;
  sel_common_sched_info.estimate_number_of_insns
    = sel_estimate_number_of_insns;
  sel_common_sched_info.luid_for_non_insn = sel_luid_for_non_insn;
  sel_common_sched_info.sched_pass_id = SCHED_SEL_PASS;

  common_sched_info = &sel_common_sched_info;

  current_sched_info = &sched_sel_haifa_sched_info;
  current_sched_info->sched_max_insns_priority =
    get_rgn_sched_max_insns_priority ();

  sel_set_sched_flags ();
}


/* Adds basic block BB to region RGN at the position *BB_ORD_INDEX,
   *BB_ORD_INDEX after that is increased.  */
static void
sel_add_block_to_region (basic_block bb, int *bb_ord_index, int rgn)
{
  RGN_NR_BLOCKS (rgn) += 1;
  RGN_DONT_CALC_DEPS (rgn) = 0;
  RGN_HAS_REAL_EBB (rgn) = 0;
  CONTAINING_RGN (bb->index) = rgn;
  BLOCK_TO_BB (bb->index) = *bb_ord_index;
  rgn_bb_table[RGN_BLOCKS (rgn) + *bb_ord_index] = bb->index;
  (*bb_ord_index)++;

  /* FIXME: it is true only when not scheduling ebbs.  */
  RGN_BLOCKS (rgn + 1) = RGN_BLOCKS (rgn) + RGN_NR_BLOCKS (rgn);
}

/* Functions to support pipelining of outer loops.  */

/* Creates a new empty region and returns it's number.  */
static int
sel_create_new_region (void)
{
  int new_rgn_number = nr_regions;

  RGN_NR_BLOCKS (new_rgn_number) = 0;

  /* FIXME: This will work only when EBBs are not created.  */
  if (new_rgn_number != 0)
    RGN_BLOCKS (new_rgn_number) = RGN_BLOCKS (new_rgn_number - 1) +
      RGN_NR_BLOCKS (new_rgn_number - 1);
  else
    RGN_BLOCKS (new_rgn_number) = 0;

  /* Set the blocks of the next region so the other functions may
     calculate the number of blocks in the region.  */
  RGN_BLOCKS (new_rgn_number + 1) = RGN_BLOCKS (new_rgn_number) +
    RGN_NR_BLOCKS (new_rgn_number);

  nr_regions++;

  return new_rgn_number;
}

/* If X has a smaller topological sort number than Y, returns -1;
   if greater, returns 1.  */
static int
bb_top_order_comparator (const void *x, const void *y)
{
  basic_block bb1 = *(const basic_block *) x;
  basic_block bb2 = *(const basic_block *) y;

  gcc_assert (bb1 == bb2
	      || rev_top_order_index[bb1->index]
		 != rev_top_order_index[bb2->index]);

  /* It's a reverse topological order in REV_TOP_ORDER_INDEX, so
     bbs with greater number should go earlier.  */
  if (rev_top_order_index[bb1->index] > rev_top_order_index[bb2->index])
    return -1;
  else
    return 1;
}

/* Create a region for LOOP and return its number.  If we don't want
   to pipeline LOOP, return -1.  */
static int
make_region_from_loop (struct loop *loop)
{
  unsigned int i;
  int new_rgn_number = -1;
  struct loop *inner;

  /* Basic block index, to be assigned to BLOCK_TO_BB.  */
  int bb_ord_index = 0;
  basic_block *loop_blocks;
  basic_block preheader_block;

  if (loop->num_nodes
      > (unsigned) PARAM_VALUE (PARAM_MAX_PIPELINE_REGION_BLOCKS))
    return -1;

  /* Don't pipeline loops whose latch belongs to some of its inner loops.  */
  for (inner = loop->inner; inner; inner = inner->inner)
    if (flow_bb_inside_loop_p (inner, loop->latch))
      return -1;

  loop->ninsns = num_loop_insns (loop);
  if ((int) loop->ninsns > PARAM_VALUE (PARAM_MAX_PIPELINE_REGION_INSNS))
    return -1;

  loop_blocks = get_loop_body_in_custom_order (loop, bb_top_order_comparator);

  for (i = 0; i < loop->num_nodes; i++)
    if (loop_blocks[i]->flags & BB_IRREDUCIBLE_LOOP)
      {
	free (loop_blocks);
	return -1;
      }

  preheader_block = loop_preheader_edge (loop)->src;
  gcc_assert (preheader_block);
  gcc_assert (loop_blocks[0] == loop->header);

  new_rgn_number = sel_create_new_region ();

  sel_add_block_to_region (preheader_block, &bb_ord_index, new_rgn_number);
  bitmap_set_bit (bbs_in_loop_rgns, preheader_block->index);

  for (i = 0; i < loop->num_nodes; i++)
    {
      /* Add only those blocks that haven't been scheduled in the inner loop.
	 The exception is the basic blocks with bookkeeping code - they should
	 be added to the region (and they actually don't belong to the loop
	 body, but to the region containing that loop body).  */

      gcc_assert (new_rgn_number >= 0);

      if (! bitmap_bit_p (bbs_in_loop_rgns, loop_blocks[i]->index))
	{
	  sel_add_block_to_region (loop_blocks[i], &bb_ord_index,
                                   new_rgn_number);
	  bitmap_set_bit (bbs_in_loop_rgns, loop_blocks[i]->index);
	}
    }

  free (loop_blocks);
  MARK_LOOP_FOR_PIPELINING (loop);

  return new_rgn_number;
}

/* Create a new region from preheader blocks LOOP_BLOCKS.  */
void
make_region_from_loop_preheader (vec<basic_block> *&loop_blocks)
{
  unsigned int i;
  int new_rgn_number = -1;
  basic_block bb;

  /* Basic block index, to be assigned to BLOCK_TO_BB.  */
  int bb_ord_index = 0;

  new_rgn_number = sel_create_new_region ();

  FOR_EACH_VEC_ELT (*loop_blocks, i, bb)
    {
      gcc_assert (new_rgn_number >= 0);

      sel_add_block_to_region (bb, &bb_ord_index, new_rgn_number);
    }

  vec_free (loop_blocks);
}


/* Create region(s) from loop nest LOOP, such that inner loops will be
   pipelined before outer loops.  Returns true when a region for LOOP
   is created.  */
static bool
make_regions_from_loop_nest (struct loop *loop)
{
  struct loop *cur_loop;
  int rgn_number;

  /* Traverse all inner nodes of the loop.  */
  for (cur_loop = loop->inner; cur_loop; cur_loop = cur_loop->next)
    if (! bitmap_bit_p (bbs_in_loop_rgns, cur_loop->header->index))
      return false;

  /* At this moment all regular inner loops should have been pipelined.
     Try to create a region from this loop.  */
  rgn_number = make_region_from_loop (loop);

  if (rgn_number < 0)
    return false;

  loop_nests.safe_push (loop);
  return true;
}

/* Initalize data structures needed.  */
void
sel_init_pipelining (void)
{
  /* Collect loop information to be used in outer loops pipelining.  */
  loop_optimizer_init (LOOPS_HAVE_PREHEADERS
                       | LOOPS_HAVE_FALLTHRU_PREHEADERS
		       | LOOPS_HAVE_RECORDED_EXITS
		       | LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS);
  current_loop_nest = NULL;

  bbs_in_loop_rgns = sbitmap_alloc (last_basic_block_for_fn (cfun));
  bitmap_clear (bbs_in_loop_rgns);

  recompute_rev_top_order ();
}

/* Returns a struct loop for region RGN.  */
loop_p
get_loop_nest_for_rgn (unsigned int rgn)
{
  /* Regions created with extend_rgns don't have corresponding loop nests,
     because they don't represent loops.  */
  if (rgn < loop_nests.length ())
    return loop_nests[rgn];
  else
    return NULL;
}

/* True when LOOP was included into pipelining regions.   */
bool
considered_for_pipelining_p (struct loop *loop)
{
  if (loop_depth (loop) == 0)
    return false;

  /* Now, the loop could be too large or irreducible.  Check whether its
     region is in LOOP_NESTS.
     We determine the region number of LOOP as the region number of its
     latch.  We can't use header here, because this header could be
     just removed preheader and it will give us the wrong region number.
     Latch can't be used because it could be in the inner loop too.  */
  if (LOOP_MARKED_FOR_PIPELINING_P (loop))
    {
      int rgn = CONTAINING_RGN (loop->latch->index);

      gcc_assert ((unsigned) rgn < loop_nests.length ());
      return true;
    }

  return false;
}

/* Makes regions from the rest of the blocks, after loops are chosen
   for pipelining.  */
static void
make_regions_from_the_rest (void)
{
  int cur_rgn_blocks;
  int *loop_hdr;
  int i;

  basic_block bb;
  edge e;
  edge_iterator ei;
  int *degree;

  /* Index in rgn_bb_table where to start allocating new regions.  */
  cur_rgn_blocks = nr_regions ? RGN_BLOCKS (nr_regions) : 0;

  /* Make regions from all the rest basic blocks - those that don't belong to
     any loop or belong to irreducible loops.  Prepare the data structures
     for extend_rgns.  */

  /* LOOP_HDR[I] == -1 if I-th bb doesn't belong to any loop,
     LOOP_HDR[I] == LOOP_HDR[J] iff basic blocks I and J reside within the same
     loop.  */
  loop_hdr = XNEWVEC (int, last_basic_block_for_fn (cfun));
  degree = XCNEWVEC (int, last_basic_block_for_fn (cfun));


  /* For each basic block that belongs to some loop assign the number
     of innermost loop it belongs to.  */
  for (i = 0; i < last_basic_block_for_fn (cfun); i++)
    loop_hdr[i] = -1;

  FOR_EACH_BB_FN (bb, cfun)
    {
      if (bb->loop_father && !bb->loop_father->num == 0
	  && !(bb->flags & BB_IRREDUCIBLE_LOOP))
	loop_hdr[bb->index] = bb->loop_father->num;
    }

  /* For each basic block degree is calculated as the number of incoming
     edges, that are going out of bbs that are not yet scheduled.
     The basic blocks that are scheduled have degree value of zero.  */
  FOR_EACH_BB_FN (bb, cfun)
    {
      degree[bb->index] = 0;

      if (!bitmap_bit_p (bbs_in_loop_rgns, bb->index))
	{
	  FOR_EACH_EDGE (e, ei, bb->preds)
	    if (!bitmap_bit_p (bbs_in_loop_rgns, e->src->index))
	      degree[bb->index]++;
	}
      else
	degree[bb->index] = -1;
    }

  extend_rgns (degree, &cur_rgn_blocks, bbs_in_loop_rgns, loop_hdr);

  /* Any block that did not end up in a region is placed into a region
     by itself.  */
  FOR_EACH_BB_FN (bb, cfun)
    if (degree[bb->index] >= 0)
      {
	rgn_bb_table[cur_rgn_blocks] = bb->index;
	RGN_NR_BLOCKS (nr_regions) = 1;
	RGN_BLOCKS (nr_regions) = cur_rgn_blocks++;
        RGN_DONT_CALC_DEPS (nr_regions) = 0;
	RGN_HAS_REAL_EBB (nr_regions) = 0;
	CONTAINING_RGN (bb->index) = nr_regions++;
	BLOCK_TO_BB (bb->index) = 0;
      }

  free (degree);
  free (loop_hdr);
}

/* Free data structures used in pipelining of loops.  */
void sel_finish_pipelining (void)
{
  struct loop *loop;

  /* Release aux fields so we don't free them later by mistake.  */
  FOR_EACH_LOOP (loop, 0)
    loop->aux = NULL;

  loop_optimizer_finalize ();

  loop_nests.release ();

  free (rev_top_order_index);
  rev_top_order_index = NULL;
}

/* This function replaces the find_rgns when
   FLAG_SEL_SCHED_PIPELINING_OUTER_LOOPS is set.  */
void
sel_find_rgns (void)
{
  sel_init_pipelining ();
  extend_regions ();

  if (current_loops)
    {
      loop_p loop;

      FOR_EACH_LOOP (loop, (flag_sel_sched_pipelining_outer_loops
			    ? LI_FROM_INNERMOST
			    : LI_ONLY_INNERMOST))
	make_regions_from_loop_nest (loop);
    }

  /* Make regions from all the rest basic blocks and schedule them.
     These blocks include blocks that don't belong to any loop or belong
     to irreducible loops.  */
  make_regions_from_the_rest ();

  /* We don't need bbs_in_loop_rgns anymore.  */
  sbitmap_free (bbs_in_loop_rgns);
  bbs_in_loop_rgns = NULL;
}

/* Add the preheader blocks from previous loop to current region taking
   it from LOOP_PREHEADER_BLOCKS (current_loop_nest) and record them in *BBS.
   This function is only used with -fsel-sched-pipelining-outer-loops.  */
void
sel_add_loop_preheaders (bb_vec_t *bbs)
{
  int i;
  basic_block bb;
  vec<basic_block> *preheader_blocks
    = LOOP_PREHEADER_BLOCKS (current_loop_nest);

  if (!preheader_blocks)
    return;

  for (i = 0; preheader_blocks->iterate (i, &bb); i++)
    {
      bbs->safe_push (bb);
      last_added_blocks.safe_push (bb);
      sel_add_bb (bb);
    }

  vec_free (preheader_blocks);
}

/* While pipelining outer loops, returns TRUE if BB is a loop preheader.
   Please note that the function should also work when pipelining_p is
   false, because it is used when deciding whether we should or should
   not reschedule pipelined code.  */
bool
sel_is_loop_preheader_p (basic_block bb)
{
  if (current_loop_nest)
    {
      struct loop *outer;

      if (preheader_removed)
        return false;

      /* Preheader is the first block in the region.  */
      if (BLOCK_TO_BB (bb->index) == 0)
        return true;

      /* We used to find a preheader with the topological information.
         Check that the above code is equivalent to what we did before.  */

      if (in_current_region_p (current_loop_nest->header))
	gcc_assert (!(BLOCK_TO_BB (bb->index)
		      < BLOCK_TO_BB (current_loop_nest->header->index)));

      /* Support the situation when the latch block of outer loop
         could be from here.  */
      for (outer = loop_outer (current_loop_nest);
	   outer;
	   outer = loop_outer (outer))
        if (considered_for_pipelining_p (outer) && outer->latch == bb)
          gcc_unreachable ();
    }

  return false;
}

/* Check whether JUMP_BB ends with a jump insn that leads only to DEST_BB and
   can be removed, making the corresponding edge fallthrough (assuming that
   all basic blocks between JUMP_BB and DEST_BB are empty).  */
static bool
bb_has_removable_jump_to_p (basic_block jump_bb, basic_block dest_bb)
{
  if (!onlyjump_p (BB_END (jump_bb))
      || tablejump_p (BB_END (jump_bb), NULL, NULL))
    return false;

  /* Several outgoing edges, abnormal edge or destination of jump is
     not DEST_BB.  */
  if (EDGE_COUNT (jump_bb->succs) != 1
      || EDGE_SUCC (jump_bb, 0)->flags & (EDGE_ABNORMAL | EDGE_CROSSING)
      || EDGE_SUCC (jump_bb, 0)->dest != dest_bb)
    return false;

  /* If not anything of the upper.  */
  return true;
}

/* Removes the loop preheader from the current region and saves it in
   PREHEADER_BLOCKS of the father loop, so they will be added later to
   region that represents an outer loop.  */
static void
sel_remove_loop_preheader (void)
{
  int i, old_len;
  int cur_rgn = CONTAINING_RGN (BB_TO_BLOCK (0));
  basic_block bb;
  bool all_empty_p = true;
  vec<basic_block> *preheader_blocks
    = LOOP_PREHEADER_BLOCKS (loop_outer (current_loop_nest));

  vec_check_alloc (preheader_blocks, 0);

  gcc_assert (current_loop_nest);
  old_len = preheader_blocks->length ();

  /* Add blocks that aren't within the current loop to PREHEADER_BLOCKS.  */
  for (i = 0; i < RGN_NR_BLOCKS (cur_rgn); i++)
    {
      bb = BASIC_BLOCK_FOR_FN (cfun, BB_TO_BLOCK (i));

      /* If the basic block belongs to region, but doesn't belong to
	 corresponding loop, then it should be a preheader.  */
      if (sel_is_loop_preheader_p (bb))
        {
          preheader_blocks->safe_push (bb);
          if (BB_END (bb) != bb_note (bb))
            all_empty_p = false;
        }
    }

  /* Remove these blocks only after iterating over the whole region.  */
  for (i = preheader_blocks->length () - 1; i >= old_len; i--)
    {
      bb =  (*preheader_blocks)[i];
      sel_remove_bb (bb, false);
    }

  if (!considered_for_pipelining_p (loop_outer (current_loop_nest)))
    {
      if (!all_empty_p)
        /* Immediately create new region from preheader.  */
        make_region_from_loop_preheader (preheader_blocks);
      else
        {
          /* If all preheader blocks are empty - dont create new empty region.
             Instead, remove them completely.  */
          FOR_EACH_VEC_ELT (*preheader_blocks, i, bb)
            {
              edge e;
              edge_iterator ei;
              basic_block prev_bb = bb->prev_bb, next_bb = bb->next_bb;

              /* Redirect all incoming edges to next basic block.  */
              for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); )
                {
                  if (! (e->flags & EDGE_FALLTHRU))
                    redirect_edge_and_branch (e, bb->next_bb);
                  else
                    redirect_edge_succ (e, bb->next_bb);
                }
              gcc_assert (BB_NOTE_LIST (bb) == NULL);
              delete_and_free_basic_block (bb);

              /* Check if after deleting preheader there is a nonconditional
                 jump in PREV_BB that leads to the next basic block NEXT_BB.
                 If it is so - delete this jump and clear data sets of its
                 basic block if it becomes empty.  */
	      if (next_bb->prev_bb == prev_bb
		  && prev_bb != ENTRY_BLOCK_PTR_FOR_FN (cfun)
                  && bb_has_removable_jump_to_p (prev_bb, next_bb))
                {
                  redirect_edge_and_branch (EDGE_SUCC (prev_bb, 0), next_bb);
                  if (BB_END (prev_bb) == bb_note (prev_bb))
                    free_data_sets (prev_bb);
                }

              set_immediate_dominator (CDI_DOMINATORS, next_bb,
                                       recompute_dominator (CDI_DOMINATORS,
                                                            next_bb));
            }
        }
      vec_free (preheader_blocks);
    }
  else
    /* Store preheader within the father's loop structure.  */
    SET_LOOP_PREHEADER_BLOCKS (loop_outer (current_loop_nest),
			       preheader_blocks);
}
#endif