summaryrefslogtreecommitdiff
path: root/gcc/gimple.c
blob: 090fc94dd2f6df9edbefa8c80710ac89a7923de6 (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
/* Gimple IR support functions.

   Copyright 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
   Contributed by Aldy Hernandez <aldyh@redhat.com>

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 "target.h"
#include "tree.h"
#include "ggc.h"
#include "hard-reg-set.h"
#include "basic-block.h"
#include "gimple.h"
#include "diagnostic.h"
#include "tree-flow.h"
#include "value-prof.h"
#include "flags.h"
#include "alias.h"
#include "demangle.h"
#include "langhooks.h"

/* Global type table.  FIXME lto, it should be possible to re-use some
   of the type hashing routines in tree.c (type_hash_canon, type_hash_lookup,
   etc), but those assume that types were built with the various
   build_*_type routines which is not the case with the streamer.  */
static GTY((if_marked ("ggc_marked_p"), param_is (union tree_node)))
  htab_t gimple_types;
static GTY((if_marked ("ggc_marked_p"), param_is (union tree_node)))
  htab_t gimple_canonical_types;
static GTY((if_marked ("tree_int_map_marked_p"), param_is (struct tree_int_map)))
  htab_t type_hash_cache;
static GTY((if_marked ("tree_int_map_marked_p"), param_is (struct tree_int_map)))
  htab_t canonical_type_hash_cache;

/* Global type comparison cache.  This is by TYPE_UID for space efficiency
   and thus cannot use and does not need GC.  */
static htab_t gtc_visited;
static struct obstack gtc_ob;

/* All the tuples have their operand vector (if present) at the very bottom
   of the structure.  Therefore, the offset required to find the
   operands vector the size of the structure minus the size of the 1
   element tree array at the end (see gimple_ops).  */
#define DEFGSSTRUCT(SYM, STRUCT, HAS_TREE_OP) \
	(HAS_TREE_OP ? sizeof (struct STRUCT) - sizeof (tree) : 0),
EXPORTED_CONST size_t gimple_ops_offset_[] = {
#include "gsstruct.def"
};
#undef DEFGSSTRUCT

#define DEFGSSTRUCT(SYM, STRUCT, HAS_TREE_OP) sizeof(struct STRUCT),
static const size_t gsstruct_code_size[] = {
#include "gsstruct.def"
};
#undef DEFGSSTRUCT

#define DEFGSCODE(SYM, NAME, GSSCODE)	NAME,
const char *const gimple_code_name[] = {
#include "gimple.def"
};
#undef DEFGSCODE

#define DEFGSCODE(SYM, NAME, GSSCODE)	GSSCODE,
EXPORTED_CONST enum gimple_statement_structure_enum gss_for_code_[] = {
#include "gimple.def"
};
#undef DEFGSCODE

#ifdef GATHER_STATISTICS
/* Gimple stats.  */

int gimple_alloc_counts[(int) gimple_alloc_kind_all];
int gimple_alloc_sizes[(int) gimple_alloc_kind_all];

/* Keep in sync with gimple.h:enum gimple_alloc_kind.  */
static const char * const gimple_alloc_kind_names[] = {
    "assignments",
    "phi nodes",
    "conditionals",
    "sequences",
    "everything else"
};

#endif /* GATHER_STATISTICS */

/* A cache of gimple_seq objects.  Sequences are created and destroyed
   fairly often during gimplification.  */
static GTY ((deletable)) struct gimple_seq_d *gimple_seq_cache;

/* Private API manipulation functions shared only with some
   other files.  */
extern void gimple_set_stored_syms (gimple, bitmap, bitmap_obstack *);
extern void gimple_set_loaded_syms (gimple, bitmap, bitmap_obstack *);

/* Gimple tuple constructors.
   Note: Any constructor taking a ``gimple_seq'' as a parameter, can
   be passed a NULL to start with an empty sequence.  */

/* Set the code for statement G to CODE.  */

static inline void
gimple_set_code (gimple g, enum gimple_code code)
{
  g->gsbase.code = code;
}

/* Return the number of bytes needed to hold a GIMPLE statement with
   code CODE.  */

static inline size_t
gimple_size (enum gimple_code code)
{
  return gsstruct_code_size[gss_for_code (code)];
}

/* Allocate memory for a GIMPLE statement with code CODE and NUM_OPS
   operands.  */

gimple
gimple_alloc_stat (enum gimple_code code, unsigned num_ops MEM_STAT_DECL)
{
  size_t size;
  gimple stmt;

  size = gimple_size (code);
  if (num_ops > 0)
    size += sizeof (tree) * (num_ops - 1);

#ifdef GATHER_STATISTICS
  {
    enum gimple_alloc_kind kind = gimple_alloc_kind (code);
    gimple_alloc_counts[(int) kind]++;
    gimple_alloc_sizes[(int) kind] += size;
  }
#endif

  stmt = ggc_alloc_cleared_gimple_statement_d_stat (size PASS_MEM_STAT);
  gimple_set_code (stmt, code);
  gimple_set_num_ops (stmt, num_ops);

  /* Do not call gimple_set_modified here as it has other side
     effects and this tuple is still not completely built.  */
  stmt->gsbase.modified = 1;

  return stmt;
}

/* Set SUBCODE to be the code of the expression computed by statement G.  */

static inline void
gimple_set_subcode (gimple g, unsigned subcode)
{
  /* We only have 16 bits for the RHS code.  Assert that we are not
     overflowing it.  */
  gcc_assert (subcode < (1 << 16));
  g->gsbase.subcode = subcode;
}



/* Build a tuple with operands.  CODE is the statement to build (which
   must be one of the GIMPLE_WITH_OPS tuples).  SUBCODE is the sub-code
   for the new tuple.  NUM_OPS is the number of operands to allocate.  */

#define gimple_build_with_ops(c, s, n) \
  gimple_build_with_ops_stat (c, s, n MEM_STAT_INFO)

static gimple
gimple_build_with_ops_stat (enum gimple_code code, unsigned subcode,
		            unsigned num_ops MEM_STAT_DECL)
{
  gimple s = gimple_alloc_stat (code, num_ops PASS_MEM_STAT);
  gimple_set_subcode (s, subcode);

  return s;
}


/* Build a GIMPLE_RETURN statement returning RETVAL.  */

gimple
gimple_build_return (tree retval)
{
  gimple s = gimple_build_with_ops (GIMPLE_RETURN, ERROR_MARK, 1);
  if (retval)
    gimple_return_set_retval (s, retval);
  return s;
}

/* Reset alias information on call S.  */

void
gimple_call_reset_alias_info (gimple s)
{
  if (gimple_call_flags (s) & ECF_CONST)
    memset (gimple_call_use_set (s), 0, sizeof (struct pt_solution));
  else
    pt_solution_reset (gimple_call_use_set (s));
  if (gimple_call_flags (s) & (ECF_CONST|ECF_PURE|ECF_NOVOPS))
    memset (gimple_call_clobber_set (s), 0, sizeof (struct pt_solution));
  else
    pt_solution_reset (gimple_call_clobber_set (s));
}

/* Helper for gimple_build_call, gimple_build_call_vec and
   gimple_build_call_from_tree.  Build the basic components of a
   GIMPLE_CALL statement to function FN with NARGS arguments.  */

static inline gimple
gimple_build_call_1 (tree fn, unsigned nargs)
{
  gimple s = gimple_build_with_ops (GIMPLE_CALL, ERROR_MARK, nargs + 3);
  if (TREE_CODE (fn) == FUNCTION_DECL)
    fn = build_fold_addr_expr (fn);
  gimple_set_op (s, 1, fn);
  gimple_call_set_fntype (s, TREE_TYPE (TREE_TYPE (fn)));
  gimple_call_reset_alias_info (s);
  return s;
}


/* Build a GIMPLE_CALL statement to function FN with the arguments
   specified in vector ARGS.  */

gimple
gimple_build_call_vec (tree fn, VEC(tree, heap) *args)
{
  unsigned i;
  unsigned nargs = VEC_length (tree, args);
  gimple call = gimple_build_call_1 (fn, nargs);

  for (i = 0; i < nargs; i++)
    gimple_call_set_arg (call, i, VEC_index (tree, args, i));

  return call;
}


/* Build a GIMPLE_CALL statement to function FN.  NARGS is the number of
   arguments.  The ... are the arguments.  */

gimple
gimple_build_call (tree fn, unsigned nargs, ...)
{
  va_list ap;
  gimple call;
  unsigned i;

  gcc_assert (TREE_CODE (fn) == FUNCTION_DECL || is_gimple_call_addr (fn));

  call = gimple_build_call_1 (fn, nargs);

  va_start (ap, nargs);
  for (i = 0; i < nargs; i++)
    gimple_call_set_arg (call, i, va_arg (ap, tree));
  va_end (ap);

  return call;
}


/* Build a GIMPLE_CALL statement from CALL_EXPR T.  Note that T is
   assumed to be in GIMPLE form already.  Minimal checking is done of
   this fact.  */

gimple
gimple_build_call_from_tree (tree t)
{
  unsigned i, nargs;
  gimple call;
  tree fndecl = get_callee_fndecl (t);

  gcc_assert (TREE_CODE (t) == CALL_EXPR);

  nargs = call_expr_nargs (t);
  call = gimple_build_call_1 (fndecl ? fndecl : CALL_EXPR_FN (t), nargs);

  for (i = 0; i < nargs; i++)
    gimple_call_set_arg (call, i, CALL_EXPR_ARG (t, i));

  gimple_set_block (call, TREE_BLOCK (t));

  /* Carry all the CALL_EXPR flags to the new GIMPLE_CALL.  */
  gimple_call_set_chain (call, CALL_EXPR_STATIC_CHAIN (t));
  gimple_call_set_tail (call, CALL_EXPR_TAILCALL (t));
  gimple_call_set_cannot_inline (call, CALL_CANNOT_INLINE_P (t));
  gimple_call_set_return_slot_opt (call, CALL_EXPR_RETURN_SLOT_OPT (t));
  gimple_call_set_from_thunk (call, CALL_FROM_THUNK_P (t));
  gimple_call_set_va_arg_pack (call, CALL_EXPR_VA_ARG_PACK (t));
  gimple_call_set_nothrow (call, TREE_NOTHROW (t));
  gimple_set_no_warning (call, TREE_NO_WARNING (t));

  return call;
}


/* Extract the operands and code for expression EXPR into *SUBCODE_P,
   *OP1_P, *OP2_P and *OP3_P respectively.  */

void
extract_ops_from_tree_1 (tree expr, enum tree_code *subcode_p, tree *op1_p,
			 tree *op2_p, tree *op3_p)
{
  enum gimple_rhs_class grhs_class;

  *subcode_p = TREE_CODE (expr);
  grhs_class = get_gimple_rhs_class (*subcode_p);

  if (grhs_class == GIMPLE_TERNARY_RHS)
    {
      *op1_p = TREE_OPERAND (expr, 0);
      *op2_p = TREE_OPERAND (expr, 1);
      *op3_p = TREE_OPERAND (expr, 2);
    }
  else if (grhs_class == GIMPLE_BINARY_RHS)
    {
      *op1_p = TREE_OPERAND (expr, 0);
      *op2_p = TREE_OPERAND (expr, 1);
      *op3_p = NULL_TREE;
    }
  else if (grhs_class == GIMPLE_UNARY_RHS)
    {
      *op1_p = TREE_OPERAND (expr, 0);
      *op2_p = NULL_TREE;
      *op3_p = NULL_TREE;
    }
  else if (grhs_class == GIMPLE_SINGLE_RHS)
    {
      *op1_p = expr;
      *op2_p = NULL_TREE;
      *op3_p = NULL_TREE;
    }
  else
    gcc_unreachable ();
}


/* Build a GIMPLE_ASSIGN statement.

   LHS of the assignment.
   RHS of the assignment which can be unary or binary.  */

gimple
gimple_build_assign_stat (tree lhs, tree rhs MEM_STAT_DECL)
{
  enum tree_code subcode;
  tree op1, op2, op3;

  extract_ops_from_tree_1 (rhs, &subcode, &op1, &op2, &op3);
  return gimple_build_assign_with_ops_stat (subcode, lhs, op1, op2, op3
  					    PASS_MEM_STAT);
}


/* Build a GIMPLE_ASSIGN statement with sub-code SUBCODE and operands
   OP1 and OP2.  If OP2 is NULL then SUBCODE must be of class
   GIMPLE_UNARY_RHS or GIMPLE_SINGLE_RHS.  */

gimple
gimple_build_assign_with_ops_stat (enum tree_code subcode, tree lhs, tree op1,
                                   tree op2, tree op3 MEM_STAT_DECL)
{
  unsigned num_ops;
  gimple p;

  /* Need 1 operand for LHS and 1 or 2 for the RHS (depending on the
     code).  */
  num_ops = get_gimple_rhs_num_ops (subcode) + 1;

  p = gimple_build_with_ops_stat (GIMPLE_ASSIGN, (unsigned)subcode, num_ops
  			          PASS_MEM_STAT);
  gimple_assign_set_lhs (p, lhs);
  gimple_assign_set_rhs1 (p, op1);
  if (op2)
    {
      gcc_assert (num_ops > 2);
      gimple_assign_set_rhs2 (p, op2);
    }

  if (op3)
    {
      gcc_assert (num_ops > 3);
      gimple_assign_set_rhs3 (p, op3);
    }

  return p;
}


/* Build a new GIMPLE_ASSIGN tuple and append it to the end of *SEQ_P.

   DST/SRC are the destination and source respectively.  You can pass
   ungimplified trees in DST or SRC, in which case they will be
   converted to a gimple operand if necessary.

   This function returns the newly created GIMPLE_ASSIGN tuple.  */

gimple
gimplify_assign (tree dst, tree src, gimple_seq *seq_p)
{
  tree t = build2 (MODIFY_EXPR, TREE_TYPE (dst), dst, src);
  gimplify_and_add (t, seq_p);
  ggc_free (t);
  return gimple_seq_last_stmt (*seq_p);
}


/* Build a GIMPLE_COND statement.

   PRED is the condition used to compare LHS and the RHS.
   T_LABEL is the label to jump to if the condition is true.
   F_LABEL is the label to jump to otherwise.  */

gimple
gimple_build_cond (enum tree_code pred_code, tree lhs, tree rhs,
		   tree t_label, tree f_label)
{
  gimple p;

  gcc_assert (TREE_CODE_CLASS (pred_code) == tcc_comparison);
  p = gimple_build_with_ops (GIMPLE_COND, pred_code, 4);
  gimple_cond_set_lhs (p, lhs);
  gimple_cond_set_rhs (p, rhs);
  gimple_cond_set_true_label (p, t_label);
  gimple_cond_set_false_label (p, f_label);
  return p;
}


/* Extract operands for a GIMPLE_COND statement out of COND_EXPR tree COND.  */

void
gimple_cond_get_ops_from_tree (tree cond, enum tree_code *code_p,
                               tree *lhs_p, tree *rhs_p)
{
  gcc_assert (TREE_CODE_CLASS (TREE_CODE (cond)) == tcc_comparison
	      || TREE_CODE (cond) == TRUTH_NOT_EXPR
	      || is_gimple_min_invariant (cond)
	      || SSA_VAR_P (cond));

  extract_ops_from_tree (cond, code_p, lhs_p, rhs_p);

  /* Canonicalize conditionals of the form 'if (!VAL)'.  */
  if (*code_p == TRUTH_NOT_EXPR)
    {
      *code_p = EQ_EXPR;
      gcc_assert (*lhs_p && *rhs_p == NULL_TREE);
      *rhs_p = build_zero_cst (TREE_TYPE (*lhs_p));
    }
  /* Canonicalize conditionals of the form 'if (VAL)'  */
  else if (TREE_CODE_CLASS (*code_p) != tcc_comparison)
    {
      *code_p = NE_EXPR;
      gcc_assert (*lhs_p && *rhs_p == NULL_TREE);
      *rhs_p = build_zero_cst (TREE_TYPE (*lhs_p));
    }
}


/* Build a GIMPLE_COND statement from the conditional expression tree
   COND.  T_LABEL and F_LABEL are as in gimple_build_cond.  */

gimple
gimple_build_cond_from_tree (tree cond, tree t_label, tree f_label)
{
  enum tree_code code;
  tree lhs, rhs;

  gimple_cond_get_ops_from_tree (cond, &code, &lhs, &rhs);
  return gimple_build_cond (code, lhs, rhs, t_label, f_label);
}

/* Set code, lhs, and rhs of a GIMPLE_COND from a suitable
   boolean expression tree COND.  */

void
gimple_cond_set_condition_from_tree (gimple stmt, tree cond)
{
  enum tree_code code;
  tree lhs, rhs;

  gimple_cond_get_ops_from_tree (cond, &code, &lhs, &rhs);
  gimple_cond_set_condition (stmt, code, lhs, rhs);
}

/* Build a GIMPLE_LABEL statement for LABEL.  */

gimple
gimple_build_label (tree label)
{
  gimple p = gimple_build_with_ops (GIMPLE_LABEL, ERROR_MARK, 1);
  gimple_label_set_label (p, label);
  return p;
}

/* Build a GIMPLE_GOTO statement to label DEST.  */

gimple
gimple_build_goto (tree dest)
{
  gimple p = gimple_build_with_ops (GIMPLE_GOTO, ERROR_MARK, 1);
  gimple_goto_set_dest (p, dest);
  return p;
}


/* Build a GIMPLE_NOP statement.  */

gimple
gimple_build_nop (void)
{
  return gimple_alloc (GIMPLE_NOP, 0);
}


/* Build a GIMPLE_BIND statement.
   VARS are the variables in BODY.
   BLOCK is the containing block.  */

gimple
gimple_build_bind (tree vars, gimple_seq body, tree block)
{
  gimple p = gimple_alloc (GIMPLE_BIND, 0);
  gimple_bind_set_vars (p, vars);
  if (body)
    gimple_bind_set_body (p, body);
  if (block)
    gimple_bind_set_block (p, block);
  return p;
}

/* Helper function to set the simple fields of a asm stmt.

   STRING is a pointer to a string that is the asm blocks assembly code.
   NINPUT is the number of register inputs.
   NOUTPUT is the number of register outputs.
   NCLOBBERS is the number of clobbered registers.
   */

static inline gimple
gimple_build_asm_1 (const char *string, unsigned ninputs, unsigned noutputs,
                    unsigned nclobbers, unsigned nlabels)
{
  gimple p;
  int size = strlen (string);

  /* ASMs with labels cannot have outputs.  This should have been
     enforced by the front end.  */
  gcc_assert (nlabels == 0 || noutputs == 0);

  p = gimple_build_with_ops (GIMPLE_ASM, ERROR_MARK,
			     ninputs + noutputs + nclobbers + nlabels);

  p->gimple_asm.ni = ninputs;
  p->gimple_asm.no = noutputs;
  p->gimple_asm.nc = nclobbers;
  p->gimple_asm.nl = nlabels;
  p->gimple_asm.string = ggc_alloc_string (string, size);

#ifdef GATHER_STATISTICS
  gimple_alloc_sizes[(int) gimple_alloc_kind (GIMPLE_ASM)] += size;
#endif

  return p;
}

/* Build a GIMPLE_ASM statement.

   STRING is the assembly code.
   NINPUT is the number of register inputs.
   NOUTPUT is the number of register outputs.
   NCLOBBERS is the number of clobbered registers.
   INPUTS is a vector of the input register parameters.
   OUTPUTS is a vector of the output register parameters.
   CLOBBERS is a vector of the clobbered register parameters.
   LABELS is a vector of destination labels.  */

gimple
gimple_build_asm_vec (const char *string, VEC(tree,gc)* inputs,
                      VEC(tree,gc)* outputs, VEC(tree,gc)* clobbers,
		      VEC(tree,gc)* labels)
{
  gimple p;
  unsigned i;

  p = gimple_build_asm_1 (string,
                          VEC_length (tree, inputs),
                          VEC_length (tree, outputs),
                          VEC_length (tree, clobbers),
			  VEC_length (tree, labels));

  for (i = 0; i < VEC_length (tree, inputs); i++)
    gimple_asm_set_input_op (p, i, VEC_index (tree, inputs, i));

  for (i = 0; i < VEC_length (tree, outputs); i++)
    gimple_asm_set_output_op (p, i, VEC_index (tree, outputs, i));

  for (i = 0; i < VEC_length (tree, clobbers); i++)
    gimple_asm_set_clobber_op (p, i, VEC_index (tree, clobbers, i));

  for (i = 0; i < VEC_length (tree, labels); i++)
    gimple_asm_set_label_op (p, i, VEC_index (tree, labels, i));

  return p;
}

/* Build a GIMPLE_CATCH statement.

  TYPES are the catch types.
  HANDLER is the exception handler.  */

gimple
gimple_build_catch (tree types, gimple_seq handler)
{
  gimple p = gimple_alloc (GIMPLE_CATCH, 0);
  gimple_catch_set_types (p, types);
  if (handler)
    gimple_catch_set_handler (p, handler);

  return p;
}

/* Build a GIMPLE_EH_FILTER statement.

   TYPES are the filter's types.
   FAILURE is the filter's failure action.  */

gimple
gimple_build_eh_filter (tree types, gimple_seq failure)
{
  gimple p = gimple_alloc (GIMPLE_EH_FILTER, 0);
  gimple_eh_filter_set_types (p, types);
  if (failure)
    gimple_eh_filter_set_failure (p, failure);

  return p;
}

/* Build a GIMPLE_EH_MUST_NOT_THROW statement.  */

gimple
gimple_build_eh_must_not_throw (tree decl)
{
  gimple p = gimple_alloc (GIMPLE_EH_MUST_NOT_THROW, 0);

  gcc_assert (TREE_CODE (decl) == FUNCTION_DECL);
  gcc_assert (flags_from_decl_or_type (decl) & ECF_NORETURN);
  gimple_eh_must_not_throw_set_fndecl (p, decl);

  return p;
}

/* Build a GIMPLE_TRY statement.

   EVAL is the expression to evaluate.
   CLEANUP is the cleanup expression.
   KIND is either GIMPLE_TRY_CATCH or GIMPLE_TRY_FINALLY depending on
   whether this is a try/catch or a try/finally respectively.  */

gimple
gimple_build_try (gimple_seq eval, gimple_seq cleanup,
    		  enum gimple_try_flags kind)
{
  gimple p;

  gcc_assert (kind == GIMPLE_TRY_CATCH || kind == GIMPLE_TRY_FINALLY);
  p = gimple_alloc (GIMPLE_TRY, 0);
  gimple_set_subcode (p, kind);
  if (eval)
    gimple_try_set_eval (p, eval);
  if (cleanup)
    gimple_try_set_cleanup (p, cleanup);

  return p;
}

/* Construct a GIMPLE_WITH_CLEANUP_EXPR statement.

   CLEANUP is the cleanup expression.  */

gimple
gimple_build_wce (gimple_seq cleanup)
{
  gimple p = gimple_alloc (GIMPLE_WITH_CLEANUP_EXPR, 0);
  if (cleanup)
    gimple_wce_set_cleanup (p, cleanup);

  return p;
}


/* Build a GIMPLE_RESX statement.  */

gimple
gimple_build_resx (int region)
{
  gimple p = gimple_build_with_ops (GIMPLE_RESX, ERROR_MARK, 0);
  p->gimple_eh_ctrl.region = region;
  return p;
}


/* The helper for constructing a gimple switch statement.
   INDEX is the switch's index.
   NLABELS is the number of labels in the switch excluding the default.
   DEFAULT_LABEL is the default label for the switch statement.  */

gimple
gimple_build_switch_nlabels (unsigned nlabels, tree index, tree default_label)
{
  /* nlabels + 1 default label + 1 index.  */
  gimple p = gimple_build_with_ops (GIMPLE_SWITCH, ERROR_MARK,
				    1 + (default_label != NULL) + nlabels);
  gimple_switch_set_index (p, index);
  if (default_label)
    gimple_switch_set_default_label (p, default_label);
  return p;
}


/* Build a GIMPLE_SWITCH statement.

   INDEX is the switch's index.
   NLABELS is the number of labels in the switch excluding the DEFAULT_LABEL.
   ... are the labels excluding the default.  */

gimple
gimple_build_switch (unsigned nlabels, tree index, tree default_label, ...)
{
  va_list al;
  unsigned i, offset;
  gimple p = gimple_build_switch_nlabels (nlabels, index, default_label);

  /* Store the rest of the labels.  */
  va_start (al, default_label);
  offset = (default_label != NULL);
  for (i = 0; i < nlabels; i++)
    gimple_switch_set_label (p, i + offset, va_arg (al, tree));
  va_end (al);

  return p;
}


/* Build a GIMPLE_SWITCH statement.

   INDEX is the switch's index.
   DEFAULT_LABEL is the default label
   ARGS is a vector of labels excluding the default.  */

gimple
gimple_build_switch_vec (tree index, tree default_label, VEC(tree, heap) *args)
{
  unsigned i, offset, nlabels = VEC_length (tree, args);
  gimple p = gimple_build_switch_nlabels (nlabels, index, default_label);

  /* Copy the labels from the vector to the switch statement.  */
  offset = (default_label != NULL);
  for (i = 0; i < nlabels; i++)
    gimple_switch_set_label (p, i + offset, VEC_index (tree, args, i));

  return p;
}

/* Build a GIMPLE_EH_DISPATCH statement.  */

gimple
gimple_build_eh_dispatch (int region)
{
  gimple p = gimple_build_with_ops (GIMPLE_EH_DISPATCH, ERROR_MARK, 0);
  p->gimple_eh_ctrl.region = region;
  return p;
}

/* Build a new GIMPLE_DEBUG_BIND statement.

   VAR is bound to VALUE; block and location are taken from STMT.  */

gimple
gimple_build_debug_bind_stat (tree var, tree value, gimple stmt MEM_STAT_DECL)
{
  gimple p = gimple_build_with_ops_stat (GIMPLE_DEBUG,
					 (unsigned)GIMPLE_DEBUG_BIND, 2
					 PASS_MEM_STAT);

  gimple_debug_bind_set_var (p, var);
  gimple_debug_bind_set_value (p, value);
  if (stmt)
    {
      gimple_set_block (p, gimple_block (stmt));
      gimple_set_location (p, gimple_location (stmt));
    }

  return p;
}


/* Build a GIMPLE_OMP_CRITICAL statement.

   BODY is the sequence of statements for which only one thread can execute.
   NAME is optional identifier for this critical block.  */

gimple
gimple_build_omp_critical (gimple_seq body, tree name)
{
  gimple p = gimple_alloc (GIMPLE_OMP_CRITICAL, 0);
  gimple_omp_critical_set_name (p, name);
  if (body)
    gimple_omp_set_body (p, body);

  return p;
}

/* Build a GIMPLE_OMP_FOR statement.

   BODY is sequence of statements inside the for loop.
   CLAUSES, are any of the OMP loop construct's clauses: private, firstprivate,
   lastprivate, reductions, ordered, schedule, and nowait.
   COLLAPSE is the collapse count.
   PRE_BODY is the sequence of statements that are loop invariant.  */

gimple
gimple_build_omp_for (gimple_seq body, tree clauses, size_t collapse,
		      gimple_seq pre_body)
{
  gimple p = gimple_alloc (GIMPLE_OMP_FOR, 0);
  if (body)
    gimple_omp_set_body (p, body);
  gimple_omp_for_set_clauses (p, clauses);
  p->gimple_omp_for.collapse = collapse;
  p->gimple_omp_for.iter
      = ggc_alloc_cleared_vec_gimple_omp_for_iter (collapse);
  if (pre_body)
    gimple_omp_for_set_pre_body (p, pre_body);

  return p;
}


/* Build a GIMPLE_OMP_PARALLEL statement.

   BODY is sequence of statements which are executed in parallel.
   CLAUSES, are the OMP parallel construct's clauses.
   CHILD_FN is the function created for the parallel threads to execute.
   DATA_ARG are the shared data argument(s).  */

gimple
gimple_build_omp_parallel (gimple_seq body, tree clauses, tree child_fn,
			   tree data_arg)
{
  gimple p = gimple_alloc (GIMPLE_OMP_PARALLEL, 0);
  if (body)
    gimple_omp_set_body (p, body);
  gimple_omp_parallel_set_clauses (p, clauses);
  gimple_omp_parallel_set_child_fn (p, child_fn);
  gimple_omp_parallel_set_data_arg (p, data_arg);

  return p;
}


/* Build a GIMPLE_OMP_TASK statement.

   BODY is sequence of statements which are executed by the explicit task.
   CLAUSES, are the OMP parallel construct's clauses.
   CHILD_FN is the function created for the parallel threads to execute.
   DATA_ARG are the shared data argument(s).
   COPY_FN is the optional function for firstprivate initialization.
   ARG_SIZE and ARG_ALIGN are size and alignment of the data block.  */

gimple
gimple_build_omp_task (gimple_seq body, tree clauses, tree child_fn,
		       tree data_arg, tree copy_fn, tree arg_size,
		       tree arg_align)
{
  gimple p = gimple_alloc (GIMPLE_OMP_TASK, 0);
  if (body)
    gimple_omp_set_body (p, body);
  gimple_omp_task_set_clauses (p, clauses);
  gimple_omp_task_set_child_fn (p, child_fn);
  gimple_omp_task_set_data_arg (p, data_arg);
  gimple_omp_task_set_copy_fn (p, copy_fn);
  gimple_omp_task_set_arg_size (p, arg_size);
  gimple_omp_task_set_arg_align (p, arg_align);

  return p;
}


/* Build a GIMPLE_OMP_SECTION statement for a sections statement.

   BODY is the sequence of statements in the section.  */

gimple
gimple_build_omp_section (gimple_seq body)
{
  gimple p = gimple_alloc (GIMPLE_OMP_SECTION, 0);
  if (body)
    gimple_omp_set_body (p, body);

  return p;
}


/* Build a GIMPLE_OMP_MASTER statement.

   BODY is the sequence of statements to be executed by just the master.  */

gimple
gimple_build_omp_master (gimple_seq body)
{
  gimple p = gimple_alloc (GIMPLE_OMP_MASTER, 0);
  if (body)
    gimple_omp_set_body (p, body);

  return p;
}


/* Build a GIMPLE_OMP_CONTINUE statement.

   CONTROL_DEF is the definition of the control variable.
   CONTROL_USE is the use of the control variable.  */

gimple
gimple_build_omp_continue (tree control_def, tree control_use)
{
  gimple p = gimple_alloc (GIMPLE_OMP_CONTINUE, 0);
  gimple_omp_continue_set_control_def (p, control_def);
  gimple_omp_continue_set_control_use (p, control_use);
  return p;
}

/* Build a GIMPLE_OMP_ORDERED statement.

   BODY is the sequence of statements inside a loop that will executed in
   sequence.  */

gimple
gimple_build_omp_ordered (gimple_seq body)
{
  gimple p = gimple_alloc (GIMPLE_OMP_ORDERED, 0);
  if (body)
    gimple_omp_set_body (p, body);

  return p;
}


/* Build a GIMPLE_OMP_RETURN statement.
   WAIT_P is true if this is a non-waiting return.  */

gimple
gimple_build_omp_return (bool wait_p)
{
  gimple p = gimple_alloc (GIMPLE_OMP_RETURN, 0);
  if (wait_p)
    gimple_omp_return_set_nowait (p);

  return p;
}


/* Build a GIMPLE_OMP_SECTIONS statement.

   BODY is a sequence of section statements.
   CLAUSES are any of the OMP sections contsruct's clauses: private,
   firstprivate, lastprivate, reduction, and nowait.  */

gimple
gimple_build_omp_sections (gimple_seq body, tree clauses)
{
  gimple p = gimple_alloc (GIMPLE_OMP_SECTIONS, 0);
  if (body)
    gimple_omp_set_body (p, body);
  gimple_omp_sections_set_clauses (p, clauses);

  return p;
}


/* Build a GIMPLE_OMP_SECTIONS_SWITCH.  */

gimple
gimple_build_omp_sections_switch (void)
{
  return gimple_alloc (GIMPLE_OMP_SECTIONS_SWITCH, 0);
}


/* Build a GIMPLE_OMP_SINGLE statement.

   BODY is the sequence of statements that will be executed once.
   CLAUSES are any of the OMP single construct's clauses: private, firstprivate,
   copyprivate, nowait.  */

gimple
gimple_build_omp_single (gimple_seq body, tree clauses)
{
  gimple p = gimple_alloc (GIMPLE_OMP_SINGLE, 0);
  if (body)
    gimple_omp_set_body (p, body);
  gimple_omp_single_set_clauses (p, clauses);

  return p;
}


/* Build a GIMPLE_OMP_ATOMIC_LOAD statement.  */

gimple
gimple_build_omp_atomic_load (tree lhs, tree rhs)
{
  gimple p = gimple_alloc (GIMPLE_OMP_ATOMIC_LOAD, 0);
  gimple_omp_atomic_load_set_lhs (p, lhs);
  gimple_omp_atomic_load_set_rhs (p, rhs);
  return p;
}

/* Build a GIMPLE_OMP_ATOMIC_STORE statement.

   VAL is the value we are storing.  */

gimple
gimple_build_omp_atomic_store (tree val)
{
  gimple p = gimple_alloc (GIMPLE_OMP_ATOMIC_STORE, 0);
  gimple_omp_atomic_store_set_val (p, val);
  return p;
}

/* Build a GIMPLE_PREDICT statement.  PREDICT is one of the predictors from
   predict.def, OUTCOME is NOT_TAKEN or TAKEN.  */

gimple
gimple_build_predict (enum br_predictor predictor, enum prediction outcome)
{
  gimple p = gimple_alloc (GIMPLE_PREDICT, 0);
  /* Ensure all the predictors fit into the lower bits of the subcode.  */
  gcc_assert ((int) END_PREDICTORS <= GF_PREDICT_TAKEN);
  gimple_predict_set_predictor (p, predictor);
  gimple_predict_set_outcome (p, outcome);
  return p;
}

#if defined ENABLE_GIMPLE_CHECKING
/* Complain of a gimple type mismatch and die.  */

void
gimple_check_failed (const_gimple gs, const char *file, int line,
		     const char *function, enum gimple_code code,
		     enum tree_code subcode)
{
  internal_error ("gimple check: expected %s(%s), have %s(%s) in %s, at %s:%d",
      		  gimple_code_name[code],
		  tree_code_name[subcode],
		  gimple_code_name[gimple_code (gs)],
		  gs->gsbase.subcode > 0
		    ? tree_code_name[gs->gsbase.subcode]
		    : "",
		  function, trim_filename (file), line);
}
#endif /* ENABLE_GIMPLE_CHECKING */


/* Allocate a new GIMPLE sequence in GC memory and return it.  If
   there are free sequences in GIMPLE_SEQ_CACHE return one of those
   instead.  */

gimple_seq
gimple_seq_alloc (void)
{
  gimple_seq seq = gimple_seq_cache;
  if (seq)
    {
      gimple_seq_cache = gimple_seq_cache->next_free;
      gcc_assert (gimple_seq_cache != seq);
      memset (seq, 0, sizeof (*seq));
    }
  else
    {
      seq = ggc_alloc_cleared_gimple_seq_d ();
#ifdef GATHER_STATISTICS
      gimple_alloc_counts[(int) gimple_alloc_kind_seq]++;
      gimple_alloc_sizes[(int) gimple_alloc_kind_seq] += sizeof (*seq);
#endif
    }

  return seq;
}

/* Return SEQ to the free pool of GIMPLE sequences.  */

void
gimple_seq_free (gimple_seq seq)
{
  if (seq == NULL)
    return;

  gcc_assert (gimple_seq_first (seq) == NULL);
  gcc_assert (gimple_seq_last (seq) == NULL);

  /* If this triggers, it's a sign that the same list is being freed
     twice.  */
  gcc_assert (seq != gimple_seq_cache || gimple_seq_cache == NULL);

  /* Add SEQ to the pool of free sequences.  */
  seq->next_free = gimple_seq_cache;
  gimple_seq_cache = seq;
}


/* Link gimple statement GS to the end of the sequence *SEQ_P.  If
   *SEQ_P is NULL, a new sequence is allocated.  */

void
gimple_seq_add_stmt (gimple_seq *seq_p, gimple gs)
{
  gimple_stmt_iterator si;

  if (gs == NULL)
    return;

  if (*seq_p == NULL)
    *seq_p = gimple_seq_alloc ();

  si = gsi_last (*seq_p);
  gsi_insert_after (&si, gs, GSI_NEW_STMT);
}


/* Append sequence SRC to the end of sequence *DST_P.  If *DST_P is
   NULL, a new sequence is allocated.  */

void
gimple_seq_add_seq (gimple_seq *dst_p, gimple_seq src)
{
  gimple_stmt_iterator si;

  if (src == NULL)
    return;

  if (*dst_p == NULL)
    *dst_p = gimple_seq_alloc ();

  si = gsi_last (*dst_p);
  gsi_insert_seq_after (&si, src, GSI_NEW_STMT);
}


/* Helper function of empty_body_p.  Return true if STMT is an empty
   statement.  */

static bool
empty_stmt_p (gimple stmt)
{
  if (gimple_code (stmt) == GIMPLE_NOP)
    return true;
  if (gimple_code (stmt) == GIMPLE_BIND)
    return empty_body_p (gimple_bind_body (stmt));
  return false;
}


/* Return true if BODY contains nothing but empty statements.  */

bool
empty_body_p (gimple_seq body)
{
  gimple_stmt_iterator i;

  if (gimple_seq_empty_p (body))
    return true;
  for (i = gsi_start (body); !gsi_end_p (i); gsi_next (&i))
    if (!empty_stmt_p (gsi_stmt (i))
	&& !is_gimple_debug (gsi_stmt (i)))
      return false;

  return true;
}


/* Perform a deep copy of sequence SRC and return the result.  */

gimple_seq
gimple_seq_copy (gimple_seq src)
{
  gimple_stmt_iterator gsi;
  gimple_seq new_seq = gimple_seq_alloc ();
  gimple stmt;

  for (gsi = gsi_start (src); !gsi_end_p (gsi); gsi_next (&gsi))
    {
      stmt = gimple_copy (gsi_stmt (gsi));
      gimple_seq_add_stmt (&new_seq, stmt);
    }

  return new_seq;
}


/* Walk all the statements in the sequence SEQ calling walk_gimple_stmt
   on each one.  WI is as in walk_gimple_stmt.

   If walk_gimple_stmt returns non-NULL, the walk is stopped, the
   value is stored in WI->CALLBACK_RESULT and the statement that
   produced the value is returned.

   Otherwise, all the statements are walked and NULL returned.  */

gimple
walk_gimple_seq (gimple_seq seq, walk_stmt_fn callback_stmt,
		 walk_tree_fn callback_op, struct walk_stmt_info *wi)
{
  gimple_stmt_iterator gsi;

  for (gsi = gsi_start (seq); !gsi_end_p (gsi); gsi_next (&gsi))
    {
      tree ret = walk_gimple_stmt (&gsi, callback_stmt, callback_op, wi);
      if (ret)
	{
	  /* If CALLBACK_STMT or CALLBACK_OP return a value, WI must exist
	     to hold it.  */
	  gcc_assert (wi);
	  wi->callback_result = ret;
	  return gsi_stmt (gsi);
	}
    }

  if (wi)
    wi->callback_result = NULL_TREE;

  return NULL;
}


/* Helper function for walk_gimple_stmt.  Walk operands of a GIMPLE_ASM.  */

static tree
walk_gimple_asm (gimple stmt, walk_tree_fn callback_op,
		 struct walk_stmt_info *wi)
{
  tree ret, op;
  unsigned noutputs;
  const char **oconstraints;
  unsigned i, n;
  const char *constraint;
  bool allows_mem, allows_reg, is_inout;

  noutputs = gimple_asm_noutputs (stmt);
  oconstraints = (const char **) alloca ((noutputs) * sizeof (const char *));

  if (wi)
    wi->is_lhs = true;

  for (i = 0; i < noutputs; i++)
    {
      op = gimple_asm_output_op (stmt, i);
      constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
      oconstraints[i] = constraint;
      parse_output_constraint (&constraint, i, 0, 0, &allows_mem, &allows_reg,
	                       &is_inout);
      if (wi)
	wi->val_only = (allows_reg || !allows_mem);
      ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
      if (ret)
	return ret;
    }

  n = gimple_asm_ninputs (stmt);
  for (i = 0; i < n; i++)
    {
      op = gimple_asm_input_op (stmt, i);
      constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
      parse_input_constraint (&constraint, 0, 0, noutputs, 0,
			      oconstraints, &allows_mem, &allows_reg);
      if (wi)
	{
	  wi->val_only = (allows_reg || !allows_mem);
          /* Although input "m" is not really a LHS, we need a lvalue.  */
	  wi->is_lhs = !wi->val_only;
	}
      ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
      if (ret)
	return ret;
    }

  if (wi)
    {
      wi->is_lhs = false;
      wi->val_only = true;
    }

  n = gimple_asm_nlabels (stmt);
  for (i = 0; i < n; i++)
    {
      op = gimple_asm_label_op (stmt, i);
      ret = walk_tree (&TREE_VALUE (op), callback_op, wi, NULL);
      if (ret)
	return ret;
    }

  return NULL_TREE;
}


/* Helper function of WALK_GIMPLE_STMT.  Walk every tree operand in
   STMT.  CALLBACK_OP and WI are as in WALK_GIMPLE_STMT.

   CALLBACK_OP is called on each operand of STMT via walk_tree.
   Additional parameters to walk_tree must be stored in WI.  For each operand
   OP, walk_tree is called as:

	walk_tree (&OP, CALLBACK_OP, WI, WI->PSET)

   If CALLBACK_OP returns non-NULL for an operand, the remaining
   operands are not scanned.

   The return value is that returned by the last call to walk_tree, or
   NULL_TREE if no CALLBACK_OP is specified.  */

tree
walk_gimple_op (gimple stmt, walk_tree_fn callback_op,
		struct walk_stmt_info *wi)
{
  struct pointer_set_t *pset = (wi) ? wi->pset : NULL;
  unsigned i;
  tree ret = NULL_TREE;

  switch (gimple_code (stmt))
    {
    case GIMPLE_ASSIGN:
      /* Walk the RHS operands.  If the LHS is of a non-renamable type or
         is a register variable, we may use a COMPONENT_REF on the RHS.  */
      if (wi)
	{
	  tree lhs = gimple_assign_lhs (stmt);
	  wi->val_only
	    = (is_gimple_reg_type (TREE_TYPE (lhs)) && !is_gimple_reg (lhs))
	      || !gimple_assign_single_p (stmt);
	}

      for (i = 1; i < gimple_num_ops (stmt); i++)
	{
	  ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi,
			   pset);
	  if (ret)
	    return ret;
	}

      /* Walk the LHS.  If the RHS is appropriate for a memory, we
	 may use a COMPONENT_REF on the LHS.  */
      if (wi)
	{
          /* If the RHS has more than 1 operand, it is not appropriate
             for the memory.  */
	  wi->val_only = !is_gimple_mem_rhs (gimple_assign_rhs1 (stmt))
                         || !gimple_assign_single_p (stmt);
	  wi->is_lhs = true;
	}

      ret = walk_tree (gimple_op_ptr (stmt, 0), callback_op, wi, pset);
      if (ret)
	return ret;

      if (wi)
	{
	  wi->val_only = true;
	  wi->is_lhs = false;
	}
      break;

    case GIMPLE_CALL:
      if (wi)
	{
	  wi->is_lhs = false;
	  wi->val_only = true;
	}

      ret = walk_tree (gimple_call_chain_ptr (stmt), callback_op, wi, pset);
      if (ret)
        return ret;

      ret = walk_tree (gimple_call_fn_ptr (stmt), callback_op, wi, pset);
      if (ret)
        return ret;

      for (i = 0; i < gimple_call_num_args (stmt); i++)
	{
	  if (wi)
	    wi->val_only = is_gimple_reg_type (gimple_call_arg (stmt, i));
	  ret = walk_tree (gimple_call_arg_ptr (stmt, i), callback_op, wi,
			   pset);
	  if (ret)
	    return ret;
	}

      if (gimple_call_lhs (stmt))
	{
	  if (wi)
	    {
	      wi->is_lhs = true;
	      wi->val_only = is_gimple_reg_type (gimple_call_lhs (stmt));
	    }

	  ret = walk_tree (gimple_call_lhs_ptr (stmt), callback_op, wi, pset);
	  if (ret)
	    return ret;
	}

      if (wi)
	{
	  wi->is_lhs = false;
	  wi->val_only = true;
	}
      break;

    case GIMPLE_CATCH:
      ret = walk_tree (gimple_catch_types_ptr (stmt), callback_op, wi,
		       pset);
      if (ret)
	return ret;
      break;

    case GIMPLE_EH_FILTER:
      ret = walk_tree (gimple_eh_filter_types_ptr (stmt), callback_op, wi,
		       pset);
      if (ret)
	return ret;
      break;

    case GIMPLE_ASM:
      ret = walk_gimple_asm (stmt, callback_op, wi);
      if (ret)
	return ret;
      break;

    case GIMPLE_OMP_CONTINUE:
      ret = walk_tree (gimple_omp_continue_control_def_ptr (stmt),
	  	       callback_op, wi, pset);
      if (ret)
	return ret;

      ret = walk_tree (gimple_omp_continue_control_use_ptr (stmt),
	  	       callback_op, wi, pset);
      if (ret)
	return ret;
      break;

    case GIMPLE_OMP_CRITICAL:
      ret = walk_tree (gimple_omp_critical_name_ptr (stmt), callback_op, wi,
		       pset);
      if (ret)
	return ret;
      break;

    case GIMPLE_OMP_FOR:
      ret = walk_tree (gimple_omp_for_clauses_ptr (stmt), callback_op, wi,
		       pset);
      if (ret)
	return ret;
      for (i = 0; i < gimple_omp_for_collapse (stmt); i++)
	{
	  ret = walk_tree (gimple_omp_for_index_ptr (stmt, i), callback_op,
			   wi, pset);
	  if (ret)
	    return ret;
	  ret = walk_tree (gimple_omp_for_initial_ptr (stmt, i), callback_op,
			   wi, pset);
	  if (ret)
	    return ret;
	  ret = walk_tree (gimple_omp_for_final_ptr (stmt, i), callback_op,
			   wi, pset);
	  if (ret)
	    return ret;
	  ret = walk_tree (gimple_omp_for_incr_ptr (stmt, i), callback_op,
			   wi, pset);
	}
      if (ret)
	return ret;
      break;

    case GIMPLE_OMP_PARALLEL:
      ret = walk_tree (gimple_omp_parallel_clauses_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      ret = walk_tree (gimple_omp_parallel_child_fn_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      ret = walk_tree (gimple_omp_parallel_data_arg_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      break;

    case GIMPLE_OMP_TASK:
      ret = walk_tree (gimple_omp_task_clauses_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      ret = walk_tree (gimple_omp_task_child_fn_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      ret = walk_tree (gimple_omp_task_data_arg_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      ret = walk_tree (gimple_omp_task_copy_fn_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      ret = walk_tree (gimple_omp_task_arg_size_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      ret = walk_tree (gimple_omp_task_arg_align_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      break;

    case GIMPLE_OMP_SECTIONS:
      ret = walk_tree (gimple_omp_sections_clauses_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;

      ret = walk_tree (gimple_omp_sections_control_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;

      break;

    case GIMPLE_OMP_SINGLE:
      ret = walk_tree (gimple_omp_single_clauses_ptr (stmt), callback_op, wi,
		       pset);
      if (ret)
	return ret;
      break;

    case GIMPLE_OMP_ATOMIC_LOAD:
      ret = walk_tree (gimple_omp_atomic_load_lhs_ptr (stmt), callback_op, wi,
		       pset);
      if (ret)
	return ret;

      ret = walk_tree (gimple_omp_atomic_load_rhs_ptr (stmt), callback_op, wi,
		       pset);
      if (ret)
	return ret;
      break;

    case GIMPLE_OMP_ATOMIC_STORE:
      ret = walk_tree (gimple_omp_atomic_store_val_ptr (stmt), callback_op,
		       wi, pset);
      if (ret)
	return ret;
      break;

      /* Tuples that do not have operands.  */
    case GIMPLE_NOP:
    case GIMPLE_RESX:
    case GIMPLE_OMP_RETURN:
    case GIMPLE_PREDICT:
      break;

    default:
      {
	enum gimple_statement_structure_enum gss;
	gss = gimple_statement_structure (stmt);
	if (gss == GSS_WITH_OPS || gss == GSS_WITH_MEM_OPS)
	  for (i = 0; i < gimple_num_ops (stmt); i++)
	    {
	      ret = walk_tree (gimple_op_ptr (stmt, i), callback_op, wi, pset);
	      if (ret)
		return ret;
	    }
      }
      break;
    }

  return NULL_TREE;
}


/* Walk the current statement in GSI (optionally using traversal state
   stored in WI).  If WI is NULL, no state is kept during traversal.
   The callback CALLBACK_STMT is called.  If CALLBACK_STMT indicates
   that it has handled all the operands of the statement, its return
   value is returned.  Otherwise, the return value from CALLBACK_STMT
   is discarded and its operands are scanned.

   If CALLBACK_STMT is NULL or it didn't handle the operands,
   CALLBACK_OP is called on each operand of the statement via
   walk_gimple_op.  If walk_gimple_op returns non-NULL for any
   operand, the remaining operands are not scanned.  In this case, the
   return value from CALLBACK_OP is returned.

   In any other case, NULL_TREE is returned.  */

tree
walk_gimple_stmt (gimple_stmt_iterator *gsi, walk_stmt_fn callback_stmt,
		  walk_tree_fn callback_op, struct walk_stmt_info *wi)
{
  gimple ret;
  tree tree_ret;
  gimple stmt = gsi_stmt (*gsi);

  if (wi)
    wi->gsi = *gsi;

  if (wi && wi->want_locations && gimple_has_location (stmt))
    input_location = gimple_location (stmt);

  ret = NULL;

  /* Invoke the statement callback.  Return if the callback handled
     all of STMT operands by itself.  */
  if (callback_stmt)
    {
      bool handled_ops = false;
      tree_ret = callback_stmt (gsi, &handled_ops, wi);
      if (handled_ops)
	return tree_ret;

      /* If CALLBACK_STMT did not handle operands, it should not have
	 a value to return.  */
      gcc_assert (tree_ret == NULL);

      /* Re-read stmt in case the callback changed it.  */
      stmt = gsi_stmt (*gsi);
    }

  /* If CALLBACK_OP is defined, invoke it on every operand of STMT.  */
  if (callback_op)
    {
      tree_ret = walk_gimple_op (stmt, callback_op, wi);
      if (tree_ret)
	return tree_ret;
    }

  /* If STMT can have statements inside (e.g. GIMPLE_BIND), walk them.  */
  switch (gimple_code (stmt))
    {
    case GIMPLE_BIND:
      ret = walk_gimple_seq (gimple_bind_body (stmt), callback_stmt,
	                     callback_op, wi);
      if (ret)
	return wi->callback_result;
      break;

    case GIMPLE_CATCH:
      ret = walk_gimple_seq (gimple_catch_handler (stmt), callback_stmt,
	                     callback_op, wi);
      if (ret)
	return wi->callback_result;
      break;

    case GIMPLE_EH_FILTER:
      ret = walk_gimple_seq (gimple_eh_filter_failure (stmt), callback_stmt,
		             callback_op, wi);
      if (ret)
	return wi->callback_result;
      break;

    case GIMPLE_TRY:
      ret = walk_gimple_seq (gimple_try_eval (stmt), callback_stmt, callback_op,
	                     wi);
      if (ret)
	return wi->callback_result;

      ret = walk_gimple_seq (gimple_try_cleanup (stmt), callback_stmt,
	                     callback_op, wi);
      if (ret)
	return wi->callback_result;
      break;

    case GIMPLE_OMP_FOR:
      ret = walk_gimple_seq (gimple_omp_for_pre_body (stmt), callback_stmt,
		             callback_op, wi);
      if (ret)
	return wi->callback_result;

      /* FALL THROUGH.  */
    case GIMPLE_OMP_CRITICAL:
    case GIMPLE_OMP_MASTER:
    case GIMPLE_OMP_ORDERED:
    case GIMPLE_OMP_SECTION:
    case GIMPLE_OMP_PARALLEL:
    case GIMPLE_OMP_TASK:
    case GIMPLE_OMP_SECTIONS:
    case GIMPLE_OMP_SINGLE:
      ret = walk_gimple_seq (gimple_omp_body (stmt), callback_stmt, callback_op,
	                     wi);
      if (ret)
	return wi->callback_result;
      break;

    case GIMPLE_WITH_CLEANUP_EXPR:
      ret = walk_gimple_seq (gimple_wce_cleanup (stmt), callback_stmt,
			     callback_op, wi);
      if (ret)
	return wi->callback_result;
      break;

    default:
      gcc_assert (!gimple_has_substatements (stmt));
      break;
    }

  return NULL;
}


/* Set sequence SEQ to be the GIMPLE body for function FN.  */

void
gimple_set_body (tree fndecl, gimple_seq seq)
{
  struct function *fn = DECL_STRUCT_FUNCTION (fndecl);
  if (fn == NULL)
    {
      /* If FNDECL still does not have a function structure associated
	 with it, then it does not make sense for it to receive a
	 GIMPLE body.  */
      gcc_assert (seq == NULL);
    }
  else
    fn->gimple_body = seq;
}


/* Return the body of GIMPLE statements for function FN.  After the
   CFG pass, the function body doesn't exist anymore because it has
   been split up into basic blocks.  In this case, it returns
   NULL.  */

gimple_seq
gimple_body (tree fndecl)
{
  struct function *fn = DECL_STRUCT_FUNCTION (fndecl);
  return fn ? fn->gimple_body : NULL;
}

/* Return true when FNDECL has Gimple body either in unlowered
   or CFG form.  */
bool
gimple_has_body_p (tree fndecl)
{
  struct function *fn = DECL_STRUCT_FUNCTION (fndecl);
  return (gimple_body (fndecl) || (fn && fn->cfg));
}

/* Detect flags from a GIMPLE_CALL.  This is just like
   call_expr_flags, but for gimple tuples.  */

int
gimple_call_flags (const_gimple stmt)
{
  int flags;
  tree decl = gimple_call_fndecl (stmt);

  if (decl)
    flags = flags_from_decl_or_type (decl);
  else
    flags = flags_from_decl_or_type (gimple_call_fntype (stmt));

  if (stmt->gsbase.subcode & GF_CALL_NOTHROW)
    flags |= ECF_NOTHROW;

  return flags;
}

/* Detects argument flags for argument number ARG on call STMT.  */

int
gimple_call_arg_flags (const_gimple stmt, unsigned arg)
{
  tree type = gimple_call_fntype (stmt);
  tree attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
  if (!attr)
    return 0;

  attr = TREE_VALUE (TREE_VALUE (attr));
  if (1 + arg >= (unsigned) TREE_STRING_LENGTH (attr))
    return 0;

  switch (TREE_STRING_POINTER (attr)[1 + arg])
    {
    case 'x':
    case 'X':
      return EAF_UNUSED;

    case 'R':
      return EAF_DIRECT | EAF_NOCLOBBER | EAF_NOESCAPE;

    case 'r':
      return EAF_NOCLOBBER | EAF_NOESCAPE;

    case 'W':
      return EAF_DIRECT | EAF_NOESCAPE;

    case 'w':
      return EAF_NOESCAPE;

    case '.':
    default:
      return 0;
    }
}

/* Detects return flags for the call STMT.  */

int
gimple_call_return_flags (const_gimple stmt)
{
  tree type;
  tree attr = NULL_TREE;

  if (gimple_call_flags (stmt) & ECF_MALLOC)
    return ERF_NOALIAS;

  type = gimple_call_fntype (stmt);
  attr = lookup_attribute ("fn spec", TYPE_ATTRIBUTES (type));
  if (!attr)
    return 0;

  attr = TREE_VALUE (TREE_VALUE (attr));
  if (TREE_STRING_LENGTH (attr) < 1)
    return 0;

  switch (TREE_STRING_POINTER (attr)[0])
    {
    case '1':
    case '2':
    case '3':
    case '4':
      return ERF_RETURNS_ARG | (TREE_STRING_POINTER (attr)[0] - '1');

    case 'm':
      return ERF_NOALIAS;

    case '.':
    default:
      return 0;
    }
}


/* Return true if GS is a copy assignment.  */

bool
gimple_assign_copy_p (gimple gs)
{
  return (gimple_assign_single_p (gs)
	  && is_gimple_val (gimple_op (gs, 1)));
}


/* Return true if GS is a SSA_NAME copy assignment.  */

bool
gimple_assign_ssa_name_copy_p (gimple gs)
{
  return (gimple_assign_single_p (gs)
	  && TREE_CODE (gimple_assign_lhs (gs)) == SSA_NAME
	  && TREE_CODE (gimple_assign_rhs1 (gs)) == SSA_NAME);
}


/* Return true if GS is an assignment with a unary RHS, but the
   operator has no effect on the assigned value.  The logic is adapted
   from STRIP_NOPS.  This predicate is intended to be used in tuplifying
   instances in which STRIP_NOPS was previously applied to the RHS of
   an assignment.

   NOTE: In the use cases that led to the creation of this function
   and of gimple_assign_single_p, it is typical to test for either
   condition and to proceed in the same manner.  In each case, the
   assigned value is represented by the single RHS operand of the
   assignment.  I suspect there may be cases where gimple_assign_copy_p,
   gimple_assign_single_p, or equivalent logic is used where a similar
   treatment of unary NOPs is appropriate.  */

bool
gimple_assign_unary_nop_p (gimple gs)
{
  return (is_gimple_assign (gs)
          && (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (gs))
              || gimple_assign_rhs_code (gs) == NON_LVALUE_EXPR)
          && gimple_assign_rhs1 (gs) != error_mark_node
          && (TYPE_MODE (TREE_TYPE (gimple_assign_lhs (gs)))
              == TYPE_MODE (TREE_TYPE (gimple_assign_rhs1 (gs)))));
}

/* Set BB to be the basic block holding G.  */

void
gimple_set_bb (gimple stmt, basic_block bb)
{
  stmt->gsbase.bb = bb;

  /* If the statement is a label, add the label to block-to-labels map
     so that we can speed up edge creation for GIMPLE_GOTOs.  */
  if (cfun->cfg && gimple_code (stmt) == GIMPLE_LABEL)
    {
      tree t;
      int uid;

      t = gimple_label_label (stmt);
      uid = LABEL_DECL_UID (t);
      if (uid == -1)
	{
	  unsigned old_len = VEC_length (basic_block, label_to_block_map);
	  LABEL_DECL_UID (t) = uid = cfun->cfg->last_label_uid++;
	  if (old_len <= (unsigned) uid)
	    {
	      unsigned new_len = 3 * uid / 2 + 1;

	      VEC_safe_grow_cleared (basic_block, gc, label_to_block_map,
				     new_len);
	    }
	}

      VEC_replace (basic_block, label_to_block_map, uid, bb);
    }
}


/* Modify the RHS of the assignment pointed-to by GSI using the
   operands in the expression tree EXPR.

   NOTE: The statement pointed-to by GSI may be reallocated if it
   did not have enough operand slots.

   This function is useful to convert an existing tree expression into
   the flat representation used for the RHS of a GIMPLE assignment.
   It will reallocate memory as needed to expand or shrink the number
   of operand slots needed to represent EXPR.

   NOTE: If you find yourself building a tree and then calling this
   function, you are most certainly doing it the slow way.  It is much
   better to build a new assignment or to use the function
   gimple_assign_set_rhs_with_ops, which does not require an
   expression tree to be built.  */

void
gimple_assign_set_rhs_from_tree (gimple_stmt_iterator *gsi, tree expr)
{
  enum tree_code subcode;
  tree op1, op2, op3;

  extract_ops_from_tree_1 (expr, &subcode, &op1, &op2, &op3);
  gimple_assign_set_rhs_with_ops_1 (gsi, subcode, op1, op2, op3);
}


/* Set the RHS of assignment statement pointed-to by GSI to CODE with
   operands OP1, OP2 and OP3.

   NOTE: The statement pointed-to by GSI may be reallocated if it
   did not have enough operand slots.  */

void
gimple_assign_set_rhs_with_ops_1 (gimple_stmt_iterator *gsi, enum tree_code code,
				  tree op1, tree op2, tree op3)
{
  unsigned new_rhs_ops = get_gimple_rhs_num_ops (code);
  gimple stmt = gsi_stmt (*gsi);

  /* If the new CODE needs more operands, allocate a new statement.  */
  if (gimple_num_ops (stmt) < new_rhs_ops + 1)
    {
      tree lhs = gimple_assign_lhs (stmt);
      gimple new_stmt = gimple_alloc (gimple_code (stmt), new_rhs_ops + 1);
      memcpy (new_stmt, stmt, gimple_size (gimple_code (stmt)));
      gsi_replace (gsi, new_stmt, true);
      stmt = new_stmt;

      /* The LHS needs to be reset as this also changes the SSA name
	 on the LHS.  */
      gimple_assign_set_lhs (stmt, lhs);
    }

  gimple_set_num_ops (stmt, new_rhs_ops + 1);
  gimple_set_subcode (stmt, code);
  gimple_assign_set_rhs1 (stmt, op1);
  if (new_rhs_ops > 1)
    gimple_assign_set_rhs2 (stmt, op2);
  if (new_rhs_ops > 2)
    gimple_assign_set_rhs3 (stmt, op3);
}


/* Return the LHS of a statement that performs an assignment,
   either a GIMPLE_ASSIGN or a GIMPLE_CALL.  Returns NULL_TREE
   for a call to a function that returns no value, or for a
   statement other than an assignment or a call.  */

tree
gimple_get_lhs (const_gimple stmt)
{
  enum gimple_code code = gimple_code (stmt);

  if (code == GIMPLE_ASSIGN)
    return gimple_assign_lhs (stmt);
  else if (code == GIMPLE_CALL)
    return gimple_call_lhs (stmt);
  else
    return NULL_TREE;
}


/* Set the LHS of a statement that performs an assignment,
   either a GIMPLE_ASSIGN or a GIMPLE_CALL.  */

void
gimple_set_lhs (gimple stmt, tree lhs)
{
  enum gimple_code code = gimple_code (stmt);

  if (code == GIMPLE_ASSIGN)
    gimple_assign_set_lhs (stmt, lhs);
  else if (code == GIMPLE_CALL)
    gimple_call_set_lhs (stmt, lhs);
  else
    gcc_unreachable();
}

/* Replace the LHS of STMT, an assignment, either a GIMPLE_ASSIGN or a
   GIMPLE_CALL, with NLHS, in preparation for modifying the RHS to an
   expression with a different value.

   This will update any annotations (say debug bind stmts) referring
   to the original LHS, so that they use the RHS instead.  This is
   done even if NLHS and LHS are the same, for it is understood that
   the RHS will be modified afterwards, and NLHS will not be assigned
   an equivalent value.

   Adjusting any non-annotation uses of the LHS, if needed, is a
   responsibility of the caller.

   The effect of this call should be pretty much the same as that of
   inserting a copy of STMT before STMT, and then removing the
   original stmt, at which time gsi_remove() would have update
   annotations, but using this function saves all the inserting,
   copying and removing.  */

void
gimple_replace_lhs (gimple stmt, tree nlhs)
{
  if (MAY_HAVE_DEBUG_STMTS)
    {
      tree lhs = gimple_get_lhs (stmt);

      gcc_assert (SSA_NAME_DEF_STMT (lhs) == stmt);

      insert_debug_temp_for_var_def (NULL, lhs);
    }

  gimple_set_lhs (stmt, nlhs);
}

/* Return a deep copy of statement STMT.  All the operands from STMT
   are reallocated and copied using unshare_expr.  The DEF, USE, VDEF
   and VUSE operand arrays are set to empty in the new copy.  */

gimple
gimple_copy (gimple stmt)
{
  enum gimple_code code = gimple_code (stmt);
  unsigned num_ops = gimple_num_ops (stmt);
  gimple copy = gimple_alloc (code, num_ops);
  unsigned i;

  /* Shallow copy all the fields from STMT.  */
  memcpy (copy, stmt, gimple_size (code));

  /* If STMT has sub-statements, deep-copy them as well.  */
  if (gimple_has_substatements (stmt))
    {
      gimple_seq new_seq;
      tree t;

      switch (gimple_code (stmt))
	{
	case GIMPLE_BIND:
	  new_seq = gimple_seq_copy (gimple_bind_body (stmt));
	  gimple_bind_set_body (copy, new_seq);
	  gimple_bind_set_vars (copy, unshare_expr (gimple_bind_vars (stmt)));
	  gimple_bind_set_block (copy, gimple_bind_block (stmt));
	  break;

	case GIMPLE_CATCH:
	  new_seq = gimple_seq_copy (gimple_catch_handler (stmt));
	  gimple_catch_set_handler (copy, new_seq);
	  t = unshare_expr (gimple_catch_types (stmt));
	  gimple_catch_set_types (copy, t);
	  break;

	case GIMPLE_EH_FILTER:
	  new_seq = gimple_seq_copy (gimple_eh_filter_failure (stmt));
	  gimple_eh_filter_set_failure (copy, new_seq);
	  t = unshare_expr (gimple_eh_filter_types (stmt));
	  gimple_eh_filter_set_types (copy, t);
	  break;

	case GIMPLE_TRY:
	  new_seq = gimple_seq_copy (gimple_try_eval (stmt));
	  gimple_try_set_eval (copy, new_seq);
	  new_seq = gimple_seq_copy (gimple_try_cleanup (stmt));
	  gimple_try_set_cleanup (copy, new_seq);
	  break;

	case GIMPLE_OMP_FOR:
	  new_seq = gimple_seq_copy (gimple_omp_for_pre_body (stmt));
	  gimple_omp_for_set_pre_body (copy, new_seq);
	  t = unshare_expr (gimple_omp_for_clauses (stmt));
	  gimple_omp_for_set_clauses (copy, t);
	  copy->gimple_omp_for.iter
	    = ggc_alloc_vec_gimple_omp_for_iter
	    (gimple_omp_for_collapse (stmt));
	  for (i = 0; i < gimple_omp_for_collapse (stmt); i++)
	    {
	      gimple_omp_for_set_cond (copy, i,
				       gimple_omp_for_cond (stmt, i));
	      gimple_omp_for_set_index (copy, i,
					gimple_omp_for_index (stmt, i));
	      t = unshare_expr (gimple_omp_for_initial (stmt, i));
	      gimple_omp_for_set_initial (copy, i, t);
	      t = unshare_expr (gimple_omp_for_final (stmt, i));
	      gimple_omp_for_set_final (copy, i, t);
	      t = unshare_expr (gimple_omp_for_incr (stmt, i));
	      gimple_omp_for_set_incr (copy, i, t);
	    }
	  goto copy_omp_body;

	case GIMPLE_OMP_PARALLEL:
	  t = unshare_expr (gimple_omp_parallel_clauses (stmt));
	  gimple_omp_parallel_set_clauses (copy, t);
	  t = unshare_expr (gimple_omp_parallel_child_fn (stmt));
	  gimple_omp_parallel_set_child_fn (copy, t);
	  t = unshare_expr (gimple_omp_parallel_data_arg (stmt));
	  gimple_omp_parallel_set_data_arg (copy, t);
	  goto copy_omp_body;

	case GIMPLE_OMP_TASK:
	  t = unshare_expr (gimple_omp_task_clauses (stmt));
	  gimple_omp_task_set_clauses (copy, t);
	  t = unshare_expr (gimple_omp_task_child_fn (stmt));
	  gimple_omp_task_set_child_fn (copy, t);
	  t = unshare_expr (gimple_omp_task_data_arg (stmt));
	  gimple_omp_task_set_data_arg (copy, t);
	  t = unshare_expr (gimple_omp_task_copy_fn (stmt));
	  gimple_omp_task_set_copy_fn (copy, t);
	  t = unshare_expr (gimple_omp_task_arg_size (stmt));
	  gimple_omp_task_set_arg_size (copy, t);
	  t = unshare_expr (gimple_omp_task_arg_align (stmt));
	  gimple_omp_task_set_arg_align (copy, t);
	  goto copy_omp_body;

	case GIMPLE_OMP_CRITICAL:
	  t = unshare_expr (gimple_omp_critical_name (stmt));
	  gimple_omp_critical_set_name (copy, t);
	  goto copy_omp_body;

	case GIMPLE_OMP_SECTIONS:
	  t = unshare_expr (gimple_omp_sections_clauses (stmt));
	  gimple_omp_sections_set_clauses (copy, t);
	  t = unshare_expr (gimple_omp_sections_control (stmt));
	  gimple_omp_sections_set_control (copy, t);
	  /* FALLTHRU  */

	case GIMPLE_OMP_SINGLE:
	case GIMPLE_OMP_SECTION:
	case GIMPLE_OMP_MASTER:
	case GIMPLE_OMP_ORDERED:
	copy_omp_body:
	  new_seq = gimple_seq_copy (gimple_omp_body (stmt));
	  gimple_omp_set_body (copy, new_seq);
	  break;

	case GIMPLE_WITH_CLEANUP_EXPR:
	  new_seq = gimple_seq_copy (gimple_wce_cleanup (stmt));
	  gimple_wce_set_cleanup (copy, new_seq);
	  break;

	default:
	  gcc_unreachable ();
	}
    }

  /* Make copy of operands.  */
  if (num_ops > 0)
    {
      for (i = 0; i < num_ops; i++)
	gimple_set_op (copy, i, unshare_expr (gimple_op (stmt, i)));

      /* Clear out SSA operand vectors on COPY.  */
      if (gimple_has_ops (stmt))
	{
	  gimple_set_def_ops (copy, NULL);
	  gimple_set_use_ops (copy, NULL);
	}

      if (gimple_has_mem_ops (stmt))
	{
	  gimple_set_vdef (copy, gimple_vdef (stmt));
	  gimple_set_vuse (copy, gimple_vuse (stmt));
	}

      /* SSA operands need to be updated.  */
      gimple_set_modified (copy, true);
    }

  return copy;
}


/* Set the MODIFIED flag to MODIFIEDP, iff the gimple statement G has
   a MODIFIED field.  */

void
gimple_set_modified (gimple s, bool modifiedp)
{
  if (gimple_has_ops (s))
    s->gsbase.modified = (unsigned) modifiedp;
}


/* Return true if statement S has side-effects.  We consider a
   statement to have side effects if:

   - It is a GIMPLE_CALL not marked with ECF_PURE or ECF_CONST.
   - Any of its operands are marked TREE_THIS_VOLATILE or TREE_SIDE_EFFECTS.  */

bool
gimple_has_side_effects (const_gimple s)
{
  unsigned i;

  if (is_gimple_debug (s))
    return false;

  /* We don't have to scan the arguments to check for
     volatile arguments, though, at present, we still
     do a scan to check for TREE_SIDE_EFFECTS.  */
  if (gimple_has_volatile_ops (s))
    return true;

  if (is_gimple_call (s))
    {
      unsigned nargs = gimple_call_num_args (s);

      if (!(gimple_call_flags (s) & (ECF_CONST | ECF_PURE)))
        return true;
      else if (gimple_call_flags (s) & ECF_LOOPING_CONST_OR_PURE)
	/* An infinite loop is considered a side effect.  */
	return true;

      if (gimple_call_lhs (s)
          && TREE_SIDE_EFFECTS (gimple_call_lhs (s)))
	{
	  gcc_assert (gimple_has_volatile_ops (s));
	  return true;
	}

      if (TREE_SIDE_EFFECTS (gimple_call_fn (s)))
        return true;

      for (i = 0; i < nargs; i++)
        if (TREE_SIDE_EFFECTS (gimple_call_arg (s, i)))
	  {
	    gcc_assert (gimple_has_volatile_ops (s));
	    return true;
	  }

      return false;
    }
  else
    {
      for (i = 0; i < gimple_num_ops (s); i++)
	if (TREE_SIDE_EFFECTS (gimple_op (s, i)))
	  {
	    gcc_assert (gimple_has_volatile_ops (s));
	    return true;
	  }
    }

  return false;
}

/* Return true if the RHS of statement S has side effects.
   We may use it to determine if it is admissable to replace
   an assignment or call with a copy of a previously-computed
   value.  In such cases, side-effects due to the LHS are
   preserved.  */

bool
gimple_rhs_has_side_effects (const_gimple s)
{
  unsigned i;

  if (is_gimple_call (s))
    {
      unsigned nargs = gimple_call_num_args (s);

      if (!(gimple_call_flags (s) & (ECF_CONST | ECF_PURE)))
        return true;

      /* We cannot use gimple_has_volatile_ops here,
         because we must ignore a volatile LHS.  */
      if (TREE_SIDE_EFFECTS (gimple_call_fn (s))
          || TREE_THIS_VOLATILE (gimple_call_fn (s)))
	{
	  gcc_assert (gimple_has_volatile_ops (s));
	  return true;
	}

      for (i = 0; i < nargs; i++)
        if (TREE_SIDE_EFFECTS (gimple_call_arg (s, i))
            || TREE_THIS_VOLATILE (gimple_call_arg (s, i)))
          return true;

      return false;
    }
  else if (is_gimple_assign (s))
    {
      /* Skip the first operand, the LHS. */
      for (i = 1; i < gimple_num_ops (s); i++)
	if (TREE_SIDE_EFFECTS (gimple_op (s, i))
            || TREE_THIS_VOLATILE (gimple_op (s, i)))
	  {
	    gcc_assert (gimple_has_volatile_ops (s));
	    return true;
	  }
    }
  else if (is_gimple_debug (s))
    return false;
  else
    {
      /* For statements without an LHS, examine all arguments.  */
      for (i = 0; i < gimple_num_ops (s); i++)
	if (TREE_SIDE_EFFECTS (gimple_op (s, i))
            || TREE_THIS_VOLATILE (gimple_op (s, i)))
	  {
	    gcc_assert (gimple_has_volatile_ops (s));
	    return true;
	  }
    }

  return false;
}

/* Helper for gimple_could_trap_p and gimple_assign_rhs_could_trap_p.
   Return true if S can trap.  When INCLUDE_MEM is true, check whether
   the memory operations could trap.  When INCLUDE_STORES is true and
   S is a GIMPLE_ASSIGN, the LHS of the assignment is also checked.  */

bool
gimple_could_trap_p_1 (gimple s, bool include_mem, bool include_stores)
{
  tree t, div = NULL_TREE;
  enum tree_code op;

  if (include_mem)
    {
      unsigned i, start = (is_gimple_assign (s) && !include_stores) ? 1 : 0;

      for (i = start; i < gimple_num_ops (s); i++)
	if (tree_could_trap_p (gimple_op (s, i)))
	  return true;
    }

  switch (gimple_code (s))
    {
    case GIMPLE_ASM:
      return gimple_asm_volatile_p (s);

    case GIMPLE_CALL:
      t = gimple_call_fndecl (s);
      /* Assume that calls to weak functions may trap.  */
      if (!t || !DECL_P (t) || DECL_WEAK (t))
	return true;
      return false;

    case GIMPLE_ASSIGN:
      t = gimple_expr_type (s);
      op = gimple_assign_rhs_code (s);
      if (get_gimple_rhs_class (op) == GIMPLE_BINARY_RHS)
	div = gimple_assign_rhs2 (s);
      return (operation_could_trap_p (op, FLOAT_TYPE_P (t),
				      (INTEGRAL_TYPE_P (t)
				       && TYPE_OVERFLOW_TRAPS (t)),
				      div));

    default:
      break;
    }

  return false;
}

/* Return true if statement S can trap.  */

bool
gimple_could_trap_p (gimple s)
{
  return gimple_could_trap_p_1 (s, true, true);
}

/* Return true if RHS of a GIMPLE_ASSIGN S can trap.  */

bool
gimple_assign_rhs_could_trap_p (gimple s)
{
  gcc_assert (is_gimple_assign (s));
  return gimple_could_trap_p_1 (s, true, false);
}


/* Print debugging information for gimple stmts generated.  */

void
dump_gimple_statistics (void)
{
#ifdef GATHER_STATISTICS
  int i, total_tuples = 0, total_bytes = 0;

  fprintf (stderr, "\nGIMPLE statements\n");
  fprintf (stderr, "Kind                   Stmts      Bytes\n");
  fprintf (stderr, "---------------------------------------\n");
  for (i = 0; i < (int) gimple_alloc_kind_all; ++i)
    {
      fprintf (stderr, "%-20s %7d %10d\n", gimple_alloc_kind_names[i],
	  gimple_alloc_counts[i], gimple_alloc_sizes[i]);
      total_tuples += gimple_alloc_counts[i];
      total_bytes += gimple_alloc_sizes[i];
    }
  fprintf (stderr, "---------------------------------------\n");
  fprintf (stderr, "%-20s %7d %10d\n", "Total", total_tuples, total_bytes);
  fprintf (stderr, "---------------------------------------\n");
#else
  fprintf (stderr, "No gimple statistics\n");
#endif
}


/* Return the number of operands needed on the RHS of a GIMPLE
   assignment for an expression with tree code CODE.  */

unsigned
get_gimple_rhs_num_ops (enum tree_code code)
{
  enum gimple_rhs_class rhs_class = get_gimple_rhs_class (code);

  if (rhs_class == GIMPLE_UNARY_RHS || rhs_class == GIMPLE_SINGLE_RHS)
    return 1;
  else if (rhs_class == GIMPLE_BINARY_RHS)
    return 2;
  else if (rhs_class == GIMPLE_TERNARY_RHS)
    return 3;
  else
    gcc_unreachable ();
}

#define DEFTREECODE(SYM, STRING, TYPE, NARGS)   			    \
  (unsigned char)							    \
  ((TYPE) == tcc_unary ? GIMPLE_UNARY_RHS				    \
   : ((TYPE) == tcc_binary						    \
      || (TYPE) == tcc_comparison) ? GIMPLE_BINARY_RHS   		    \
   : ((TYPE) == tcc_constant						    \
      || (TYPE) == tcc_declaration					    \
      || (TYPE) == tcc_reference) ? GIMPLE_SINGLE_RHS			    \
   : ((SYM) == TRUTH_AND_EXPR						    \
      || (SYM) == TRUTH_OR_EXPR						    \
      || (SYM) == TRUTH_XOR_EXPR) ? GIMPLE_BINARY_RHS			    \
   : (SYM) == TRUTH_NOT_EXPR ? GIMPLE_UNARY_RHS				    \
   : ((SYM) == WIDEN_MULT_PLUS_EXPR					    \
      || (SYM) == WIDEN_MULT_MINUS_EXPR					    \
      || (SYM) == DOT_PROD_EXPR						    \
      || (SYM) == REALIGN_LOAD_EXPR					    \
      || (SYM) == FMA_EXPR) ? GIMPLE_TERNARY_RHS			    \
   : ((SYM) == COND_EXPR						    \
      || (SYM) == CONSTRUCTOR						    \
      || (SYM) == OBJ_TYPE_REF						    \
      || (SYM) == ASSERT_EXPR						    \
      || (SYM) == ADDR_EXPR						    \
      || (SYM) == WITH_SIZE_EXPR					    \
      || (SYM) == SSA_NAME						    \
      || (SYM) == VEC_COND_EXPR) ? GIMPLE_SINGLE_RHS			    \
   : GIMPLE_INVALID_RHS),
#define END_OF_BASE_TREE_CODES (unsigned char) GIMPLE_INVALID_RHS,

const unsigned char gimple_rhs_class_table[] = {
#include "all-tree.def"
};

#undef DEFTREECODE
#undef END_OF_BASE_TREE_CODES

/* For the definitive definition of GIMPLE, see doc/tree-ssa.texi.  */

/* Validation of GIMPLE expressions.  */

/* Returns true iff T is a valid RHS for an assignment to a renamed
   user -- or front-end generated artificial -- variable.  */

bool
is_gimple_reg_rhs (tree t)
{
  return get_gimple_rhs_class (TREE_CODE (t)) != GIMPLE_INVALID_RHS;
}

/* Returns true iff T is a valid RHS for an assignment to an un-renamed
   LHS, or for a call argument.  */

bool
is_gimple_mem_rhs (tree t)
{
  /* If we're dealing with a renamable type, either source or dest must be
     a renamed variable.  */
  if (is_gimple_reg_type (TREE_TYPE (t)))
    return is_gimple_val (t);
  else
    return is_gimple_val (t) || is_gimple_lvalue (t);
}

/*  Return true if T is a valid LHS for a GIMPLE assignment expression.  */

bool
is_gimple_lvalue (tree t)
{
  return (is_gimple_addressable (t)
	  || TREE_CODE (t) == WITH_SIZE_EXPR
	  /* These are complex lvalues, but don't have addresses, so they
	     go here.  */
	  || TREE_CODE (t) == BIT_FIELD_REF);
}

/*  Return true if T is a GIMPLE condition.  */

bool
is_gimple_condexpr (tree t)
{
  return (is_gimple_val (t) || (COMPARISON_CLASS_P (t)
				&& !tree_could_throw_p (t)
				&& is_gimple_val (TREE_OPERAND (t, 0))
				&& is_gimple_val (TREE_OPERAND (t, 1))));
}

/*  Return true if T is something whose address can be taken.  */

bool
is_gimple_addressable (tree t)
{
  return (is_gimple_id (t) || handled_component_p (t)
	  || TREE_CODE (t) == MEM_REF);
}

/* Return true if T is a valid gimple constant.  */

bool
is_gimple_constant (const_tree t)
{
  switch (TREE_CODE (t))
    {
    case INTEGER_CST:
    case REAL_CST:
    case FIXED_CST:
    case STRING_CST:
    case COMPLEX_CST:
    case VECTOR_CST:
      return true;

    /* Vector constant constructors are gimple invariant.  */
    case CONSTRUCTOR:
      if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
	return TREE_CONSTANT (t);
      else
	return false;

    default:
      return false;
    }
}

/* Return true if T is a gimple address.  */

bool
is_gimple_address (const_tree t)
{
  tree op;

  if (TREE_CODE (t) != ADDR_EXPR)
    return false;

  op = TREE_OPERAND (t, 0);
  while (handled_component_p (op))
    {
      if ((TREE_CODE (op) == ARRAY_REF
	   || TREE_CODE (op) == ARRAY_RANGE_REF)
	  && !is_gimple_val (TREE_OPERAND (op, 1)))
	    return false;

      op = TREE_OPERAND (op, 0);
    }

  if (CONSTANT_CLASS_P (op) || TREE_CODE (op) == MEM_REF)
    return true;

  switch (TREE_CODE (op))
    {
    case PARM_DECL:
    case RESULT_DECL:
    case LABEL_DECL:
    case FUNCTION_DECL:
    case VAR_DECL:
    case CONST_DECL:
      return true;

    default:
      return false;
    }
}

/* Strip out all handled components that produce invariant
   offsets.  */

static const_tree
strip_invariant_refs (const_tree op)
{
  while (handled_component_p (op))
    {
      switch (TREE_CODE (op))
	{
	case ARRAY_REF:
	case ARRAY_RANGE_REF:
	  if (!is_gimple_constant (TREE_OPERAND (op, 1))
	      || TREE_OPERAND (op, 2) != NULL_TREE
	      || TREE_OPERAND (op, 3) != NULL_TREE)
	    return NULL;
	  break;

	case COMPONENT_REF:
	  if (TREE_OPERAND (op, 2) != NULL_TREE)
	    return NULL;
	  break;

	default:;
	}
      op = TREE_OPERAND (op, 0);
    }

  return op;
}

/* Return true if T is a gimple invariant address.  */

bool
is_gimple_invariant_address (const_tree t)
{
  const_tree op;

  if (TREE_CODE (t) != ADDR_EXPR)
    return false;

  op = strip_invariant_refs (TREE_OPERAND (t, 0));
  if (!op)
    return false;

  if (TREE_CODE (op) == MEM_REF)
    {
      const_tree op0 = TREE_OPERAND (op, 0);
      return (TREE_CODE (op0) == ADDR_EXPR
	      && (CONSTANT_CLASS_P (TREE_OPERAND (op0, 0))
		  || decl_address_invariant_p (TREE_OPERAND (op0, 0))));
    }

  return CONSTANT_CLASS_P (op) || decl_address_invariant_p (op);
}

/* Return true if T is a gimple invariant address at IPA level
   (so addresses of variables on stack are not allowed).  */

bool
is_gimple_ip_invariant_address (const_tree t)
{
  const_tree op;

  if (TREE_CODE (t) != ADDR_EXPR)
    return false;

  op = strip_invariant_refs (TREE_OPERAND (t, 0));

  return op && (CONSTANT_CLASS_P (op) || decl_address_ip_invariant_p (op));
}

/* Return true if T is a GIMPLE minimal invariant.  It's a restricted
   form of function invariant.  */

bool
is_gimple_min_invariant (const_tree t)
{
  if (TREE_CODE (t) == ADDR_EXPR)
    return is_gimple_invariant_address (t);

  return is_gimple_constant (t);
}

/* Return true if T is a GIMPLE interprocedural invariant.  It's a restricted
   form of gimple minimal invariant.  */

bool
is_gimple_ip_invariant (const_tree t)
{
  if (TREE_CODE (t) == ADDR_EXPR)
    return is_gimple_ip_invariant_address (t);

  return is_gimple_constant (t);
}

/* Return true if T looks like a valid GIMPLE statement.  */

bool
is_gimple_stmt (tree t)
{
  const enum tree_code code = TREE_CODE (t);

  switch (code)
    {
    case NOP_EXPR:
      /* The only valid NOP_EXPR is the empty statement.  */
      return IS_EMPTY_STMT (t);

    case BIND_EXPR:
    case COND_EXPR:
      /* These are only valid if they're void.  */
      return TREE_TYPE (t) == NULL || VOID_TYPE_P (TREE_TYPE (t));

    case SWITCH_EXPR:
    case GOTO_EXPR:
    case RETURN_EXPR:
    case LABEL_EXPR:
    case CASE_LABEL_EXPR:
    case TRY_CATCH_EXPR:
    case TRY_FINALLY_EXPR:
    case EH_FILTER_EXPR:
    case CATCH_EXPR:
    case ASM_EXPR:
    case STATEMENT_LIST:
    case OMP_PARALLEL:
    case OMP_FOR:
    case OMP_SECTIONS:
    case OMP_SECTION:
    case OMP_SINGLE:
    case OMP_MASTER:
    case OMP_ORDERED:
    case OMP_CRITICAL:
    case OMP_TASK:
      /* These are always void.  */
      return true;

    case CALL_EXPR:
    case MODIFY_EXPR:
    case PREDICT_EXPR:
      /* These are valid regardless of their type.  */
      return true;

    default:
      return false;
    }
}

/* Return true if T is a variable.  */

bool
is_gimple_variable (tree t)
{
  return (TREE_CODE (t) == VAR_DECL
	  || TREE_CODE (t) == PARM_DECL
	  || TREE_CODE (t) == RESULT_DECL
	  || TREE_CODE (t) == SSA_NAME);
}

/*  Return true if T is a GIMPLE identifier (something with an address).  */

bool
is_gimple_id (tree t)
{
  return (is_gimple_variable (t)
	  || TREE_CODE (t) == FUNCTION_DECL
	  || TREE_CODE (t) == LABEL_DECL
	  || TREE_CODE (t) == CONST_DECL
	  /* Allow string constants, since they are addressable.  */
	  || TREE_CODE (t) == STRING_CST);
}

/* Return true if TYPE is a suitable type for a scalar register variable.  */

bool
is_gimple_reg_type (tree type)
{
  return !AGGREGATE_TYPE_P (type);
}

/* Return true if T is a non-aggregate register variable.  */

bool
is_gimple_reg (tree t)
{
  if (TREE_CODE (t) == SSA_NAME)
    t = SSA_NAME_VAR (t);

  if (!is_gimple_variable (t))
    return false;

  if (!is_gimple_reg_type (TREE_TYPE (t)))
    return false;

  /* A volatile decl is not acceptable because we can't reuse it as
     needed.  We need to copy it into a temp first.  */
  if (TREE_THIS_VOLATILE (t))
    return false;

  /* We define "registers" as things that can be renamed as needed,
     which with our infrastructure does not apply to memory.  */
  if (needs_to_live_in_memory (t))
    return false;

  /* Hard register variables are an interesting case.  For those that
     are call-clobbered, we don't know where all the calls are, since
     we don't (want to) take into account which operations will turn
     into libcalls at the rtl level.  For those that are call-saved,
     we don't currently model the fact that calls may in fact change
     global hard registers, nor do we examine ASM_CLOBBERS at the tree
     level, and so miss variable changes that might imply.  All around,
     it seems safest to not do too much optimization with these at the
     tree level at all.  We'll have to rely on the rtl optimizers to
     clean this up, as there we've got all the appropriate bits exposed.  */
  if (TREE_CODE (t) == VAR_DECL && DECL_HARD_REGISTER (t))
    return false;

  /* Complex and vector values must have been put into SSA-like form.
     That is, no assignments to the individual components.  */
  if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE
      || TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
    return DECL_GIMPLE_REG_P (t);

  return true;
}


/* Return true if T is a GIMPLE variable whose address is not needed.  */

bool
is_gimple_non_addressable (tree t)
{
  if (TREE_CODE (t) == SSA_NAME)
    t = SSA_NAME_VAR (t);

  return (is_gimple_variable (t) && ! needs_to_live_in_memory (t));
}

/* Return true if T is a GIMPLE rvalue, i.e. an identifier or a constant.  */

bool
is_gimple_val (tree t)
{
  /* Make loads from volatiles and memory vars explicit.  */
  if (is_gimple_variable (t)
      && is_gimple_reg_type (TREE_TYPE (t))
      && !is_gimple_reg (t))
    return false;

  return (is_gimple_variable (t) || is_gimple_min_invariant (t));
}

/* Similarly, but accept hard registers as inputs to asm statements.  */

bool
is_gimple_asm_val (tree t)
{
  if (TREE_CODE (t) == VAR_DECL && DECL_HARD_REGISTER (t))
    return true;

  return is_gimple_val (t);
}

/* Return true if T is a GIMPLE minimal lvalue.  */

bool
is_gimple_min_lval (tree t)
{
  if (!(t = CONST_CAST_TREE (strip_invariant_refs (t))))
    return false;
  return (is_gimple_id (t) || TREE_CODE (t) == MEM_REF);
}

/* Return true if T is a valid function operand of a CALL_EXPR.  */

bool
is_gimple_call_addr (tree t)
{
  return (TREE_CODE (t) == OBJ_TYPE_REF || is_gimple_val (t));
}

/* Return true if T is a valid address operand of a MEM_REF.  */

bool
is_gimple_mem_ref_addr (tree t)
{
  return (is_gimple_reg (t)
	  || TREE_CODE (t) == INTEGER_CST
	  || (TREE_CODE (t) == ADDR_EXPR
	      && (CONSTANT_CLASS_P (TREE_OPERAND (t, 0))
		  || decl_address_invariant_p (TREE_OPERAND (t, 0)))));
}

/* If T makes a function call, return the corresponding CALL_EXPR operand.
   Otherwise, return NULL_TREE.  */

tree
get_call_expr_in (tree t)
{
  if (TREE_CODE (t) == MODIFY_EXPR)
    t = TREE_OPERAND (t, 1);
  if (TREE_CODE (t) == WITH_SIZE_EXPR)
    t = TREE_OPERAND (t, 0);
  if (TREE_CODE (t) == CALL_EXPR)
    return t;
  return NULL_TREE;
}


/* Given a memory reference expression T, return its base address.
   The base address of a memory reference expression is the main
   object being referenced.  For instance, the base address for
   'array[i].fld[j]' is 'array'.  You can think of this as stripping
   away the offset part from a memory address.

   This function calls handled_component_p to strip away all the inner
   parts of the memory reference until it reaches the base object.  */

tree
get_base_address (tree t)
{
  while (handled_component_p (t))
    t = TREE_OPERAND (t, 0);

  if ((TREE_CODE (t) == MEM_REF
       || TREE_CODE (t) == TARGET_MEM_REF)
      && TREE_CODE (TREE_OPERAND (t, 0)) == ADDR_EXPR)
    t = TREE_OPERAND (TREE_OPERAND (t, 0), 0);

  if (TREE_CODE (t) == SSA_NAME
      || DECL_P (t)
      || TREE_CODE (t) == STRING_CST
      || TREE_CODE (t) == CONSTRUCTOR
      || INDIRECT_REF_P (t)
      || TREE_CODE (t) == MEM_REF
      || TREE_CODE (t) == TARGET_MEM_REF)
    return t;
  else
    return NULL_TREE;
}

void
recalculate_side_effects (tree t)
{
  enum tree_code code = TREE_CODE (t);
  int len = TREE_OPERAND_LENGTH (t);
  int i;

  switch (TREE_CODE_CLASS (code))
    {
    case tcc_expression:
      switch (code)
	{
	case INIT_EXPR:
	case MODIFY_EXPR:
	case VA_ARG_EXPR:
	case PREDECREMENT_EXPR:
	case PREINCREMENT_EXPR:
	case POSTDECREMENT_EXPR:
	case POSTINCREMENT_EXPR:
	  /* All of these have side-effects, no matter what their
	     operands are.  */
	  return;

	default:
	  break;
	}
      /* Fall through.  */

    case tcc_comparison:  /* a comparison expression */
    case tcc_unary:       /* a unary arithmetic expression */
    case tcc_binary:      /* a binary arithmetic expression */
    case tcc_reference:   /* a reference */
    case tcc_vl_exp:        /* a function call */
      TREE_SIDE_EFFECTS (t) = TREE_THIS_VOLATILE (t);
      for (i = 0; i < len; ++i)
	{
	  tree op = TREE_OPERAND (t, i);
	  if (op && TREE_SIDE_EFFECTS (op))
	    TREE_SIDE_EFFECTS (t) = 1;
	}
      break;

    case tcc_constant:
      /* No side-effects.  */
      return;

    default:
      gcc_unreachable ();
   }
}

/* Canonicalize a tree T for use in a COND_EXPR as conditional.  Returns
   a canonicalized tree that is valid for a COND_EXPR or NULL_TREE, if
   we failed to create one.  */

tree
canonicalize_cond_expr_cond (tree t)
{
  /* Strip conversions around boolean operations.  */
  if (CONVERT_EXPR_P (t)
      && truth_value_p (TREE_CODE (TREE_OPERAND (t, 0))))
    t = TREE_OPERAND (t, 0);

  /* For (bool)x use x != 0.  */
  if (CONVERT_EXPR_P (t)
      && TREE_CODE (TREE_TYPE (t)) == BOOLEAN_TYPE)
    {
      tree top0 = TREE_OPERAND (t, 0);
      t = build2 (NE_EXPR, TREE_TYPE (t),
		  top0, build_int_cst (TREE_TYPE (top0), 0));
    }
  /* For !x use x == 0.  */
  else if (TREE_CODE (t) == TRUTH_NOT_EXPR)
    {
      tree top0 = TREE_OPERAND (t, 0);
      t = build2 (EQ_EXPR, TREE_TYPE (t),
		  top0, build_int_cst (TREE_TYPE (top0), 0));
    }
  /* For cmp ? 1 : 0 use cmp.  */
  else if (TREE_CODE (t) == COND_EXPR
	   && COMPARISON_CLASS_P (TREE_OPERAND (t, 0))
	   && integer_onep (TREE_OPERAND (t, 1))
	   && integer_zerop (TREE_OPERAND (t, 2)))
    {
      tree top0 = TREE_OPERAND (t, 0);
      t = build2 (TREE_CODE (top0), TREE_TYPE (t),
		  TREE_OPERAND (top0, 0), TREE_OPERAND (top0, 1));
    }

  if (is_gimple_condexpr (t))
    return t;

  return NULL_TREE;
}

/* Build a GIMPLE_CALL identical to STMT but skipping the arguments in
   the positions marked by the set ARGS_TO_SKIP.  */

gimple
gimple_call_copy_skip_args (gimple stmt, bitmap args_to_skip)
{
  int i;
  tree fn = gimple_call_fn (stmt);
  int nargs = gimple_call_num_args (stmt);
  VEC(tree, heap) *vargs = VEC_alloc (tree, heap, nargs);
  gimple new_stmt;

  for (i = 0; i < nargs; i++)
    if (!bitmap_bit_p (args_to_skip, i))
      VEC_quick_push (tree, vargs, gimple_call_arg (stmt, i));

  new_stmt = gimple_build_call_vec (fn, vargs);
  VEC_free (tree, heap, vargs);
  if (gimple_call_lhs (stmt))
    gimple_call_set_lhs (new_stmt, gimple_call_lhs (stmt));

  gimple_set_vuse (new_stmt, gimple_vuse (stmt));
  gimple_set_vdef (new_stmt, gimple_vdef (stmt));

  gimple_set_block (new_stmt, gimple_block (stmt));
  if (gimple_has_location (stmt))
    gimple_set_location (new_stmt, gimple_location (stmt));
  gimple_call_copy_flags (new_stmt, stmt);
  gimple_call_set_chain (new_stmt, gimple_call_chain (stmt));

  gimple_set_modified (new_stmt, true);

  return new_stmt;
}


static hashval_t gimple_type_hash_1 (const void *, enum gtc_mode);

/* Structure used to maintain a cache of some type pairs compared by
   gimple_types_compatible_p when comparing aggregate types.  There are
   three possible values for SAME_P:

   	-2: The pair (T1, T2) has just been inserted in the table.
	 0: T1 and T2 are different types.
	 1: T1 and T2 are the same type.

   The two elements in the SAME_P array are indexed by the comparison
   mode gtc_mode.  */

struct type_pair_d
{
  unsigned int uid1;
  unsigned int uid2;
  signed char same_p[2];
};
typedef struct type_pair_d *type_pair_t;

DEF_VEC_P(type_pair_t);
DEF_VEC_ALLOC_P(type_pair_t,heap);

/* Return a hash value for the type pair pointed-to by P.  */

static hashval_t
type_pair_hash (const void *p)
{
  const struct type_pair_d *pair = (const struct type_pair_d *) p;
  hashval_t val1 = pair->uid1;
  hashval_t val2 = pair->uid2;
  return (iterative_hash_hashval_t (val2, val1)
	  ^ iterative_hash_hashval_t (val1, val2));
}

/* Compare two type pairs pointed-to by P1 and P2.  */

static int
type_pair_eq (const void *p1, const void *p2)
{
  const struct type_pair_d *pair1 = (const struct type_pair_d *) p1;
  const struct type_pair_d *pair2 = (const struct type_pair_d *) p2;
  return ((pair1->uid1 == pair2->uid1 && pair1->uid2 == pair2->uid2)
	  || (pair1->uid1 == pair2->uid2 && pair1->uid2 == pair2->uid1));
}

/* Lookup the pair of types T1 and T2 in *VISITED_P.  Insert a new
   entry if none existed.  */

static type_pair_t
lookup_type_pair (tree t1, tree t2, htab_t *visited_p, struct obstack *ob_p)
{
  struct type_pair_d pair;
  type_pair_t p;
  void **slot;

  if (*visited_p == NULL)
    {
      *visited_p = htab_create (251, type_pair_hash, type_pair_eq, NULL);
      gcc_obstack_init (ob_p);
    }

  pair.uid1 = TYPE_UID (t1);
  pair.uid2 = TYPE_UID (t2);
  slot = htab_find_slot (*visited_p, &pair, INSERT);

  if (*slot)
    p = *((type_pair_t *) slot);
  else
    {
      p = XOBNEW (ob_p, struct type_pair_d);
      p->uid1 = TYPE_UID (t1);
      p->uid2 = TYPE_UID (t2);
      p->same_p[0] = -2;
      p->same_p[1] = -2;
      *slot = (void *) p;
    }

  return p;
}

/* Per pointer state for the SCC finding.  The on_sccstack flag
   is not strictly required, it is true when there is no hash value
   recorded for the type and false otherwise.  But querying that
   is slower.  */

struct sccs
{
  unsigned int dfsnum;
  unsigned int low;
  bool on_sccstack;
  union {
    hashval_t hash;
    signed char same_p;
  } u;
};

static unsigned int next_dfs_num;
static unsigned int gtc_next_dfs_num;


/* GIMPLE type merging cache.  A direct-mapped cache based on TYPE_UID.  */

typedef struct GTY(()) gimple_type_leader_entry_s {
  tree type;
  tree leader;
} gimple_type_leader_entry;

#define GIMPLE_TYPE_LEADER_SIZE 16381
static GTY((deletable, length("GIMPLE_TYPE_LEADER_SIZE")))
  gimple_type_leader_entry *gimple_type_leader;

/* Lookup an existing leader for T and return it or NULL_TREE, if
   there is none in the cache.  */

static tree
gimple_lookup_type_leader (tree t)
{
  gimple_type_leader_entry *leader;

  if (!gimple_type_leader)
    return NULL_TREE;

  leader = &gimple_type_leader[TYPE_UID (t) % GIMPLE_TYPE_LEADER_SIZE];
  if (leader->type != t)
    return NULL_TREE;

  return leader->leader;
}

/* Return true if T1 and T2 have the same name.  If FOR_COMPLETION_P is
   true then if any type has no name return false, otherwise return
   true if both types have no names.  */

static bool
compare_type_names_p (tree t1, tree t2, bool for_completion_p)
{
  tree name1 = TYPE_NAME (t1);
  tree name2 = TYPE_NAME (t2);

  /* Consider anonymous types all unique for completion.  */
  if (for_completion_p
      && (!name1 || !name2))
    return false;

  if (name1 && TREE_CODE (name1) == TYPE_DECL)
    {
      name1 = DECL_NAME (name1);
      if (for_completion_p
	  && !name1)
	return false;
    }
  gcc_assert (!name1 || TREE_CODE (name1) == IDENTIFIER_NODE);

  if (name2 && TREE_CODE (name2) == TYPE_DECL)
    {
      name2 = DECL_NAME (name2);
      if (for_completion_p
	  && !name2)
	return false;
    }
  gcc_assert (!name2 || TREE_CODE (name2) == IDENTIFIER_NODE);

  /* Identifiers can be compared with pointer equality rather
     than a string comparison.  */
  if (name1 == name2)
    return true;

  return false;
}

/* Return true if the field decls F1 and F2 are at the same offset.

   This is intended to be used on GIMPLE types only.  */

bool
gimple_compare_field_offset (tree f1, tree f2)
{
  if (DECL_OFFSET_ALIGN (f1) == DECL_OFFSET_ALIGN (f2))
    {
      tree offset1 = DECL_FIELD_OFFSET (f1);
      tree offset2 = DECL_FIELD_OFFSET (f2);
      return ((offset1 == offset2
	       /* Once gimplification is done, self-referential offsets are
		  instantiated as operand #2 of the COMPONENT_REF built for
		  each access and reset.  Therefore, they are not relevant
		  anymore and fields are interchangeable provided that they
		  represent the same access.  */
	       || (TREE_CODE (offset1) == PLACEHOLDER_EXPR
		   && TREE_CODE (offset2) == PLACEHOLDER_EXPR
		   && (DECL_SIZE (f1) == DECL_SIZE (f2)
		       || (TREE_CODE (DECL_SIZE (f1)) == PLACEHOLDER_EXPR
			   && TREE_CODE (DECL_SIZE (f2)) == PLACEHOLDER_EXPR)
		       || operand_equal_p (DECL_SIZE (f1), DECL_SIZE (f2), 0))
		   && DECL_ALIGN (f1) == DECL_ALIGN (f2))
	       || operand_equal_p (offset1, offset2, 0))
	      && tree_int_cst_equal (DECL_FIELD_BIT_OFFSET (f1),
				     DECL_FIELD_BIT_OFFSET (f2)));
    }

  /* Fortran and C do not always agree on what DECL_OFFSET_ALIGN
     should be, so handle differing ones specially by decomposing
     the offset into a byte and bit offset manually.  */
  if (host_integerp (DECL_FIELD_OFFSET (f1), 0)
      && host_integerp (DECL_FIELD_OFFSET (f2), 0))
    {
      unsigned HOST_WIDE_INT byte_offset1, byte_offset2;
      unsigned HOST_WIDE_INT bit_offset1, bit_offset2;
      bit_offset1 = TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (f1));
      byte_offset1 = (TREE_INT_CST_LOW (DECL_FIELD_OFFSET (f1))
		      + bit_offset1 / BITS_PER_UNIT);
      bit_offset2 = TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (f2));
      byte_offset2 = (TREE_INT_CST_LOW (DECL_FIELD_OFFSET (f2))
		      + bit_offset2 / BITS_PER_UNIT);
      if (byte_offset1 != byte_offset2)
	return false;
      return bit_offset1 % BITS_PER_UNIT == bit_offset2 % BITS_PER_UNIT;
    }

  return false;
}

/* If the type T1 and the type T2 are a complete and an incomplete
   variant of the same type return true.  */

static bool
gimple_compatible_complete_and_incomplete_subtype_p (tree t1, tree t2)
{
  /* If one pointer points to an incomplete type variant of
     the other pointed-to type they are the same.  */
  if (TREE_CODE (t1) == TREE_CODE (t2)
      && RECORD_OR_UNION_TYPE_P (t1)
      && (!COMPLETE_TYPE_P (t1)
	  || !COMPLETE_TYPE_P (t2))
      && TYPE_QUALS (t1) == TYPE_QUALS (t2)
      && compare_type_names_p (TYPE_MAIN_VARIANT (t1),
			       TYPE_MAIN_VARIANT (t2), true))
    return true;
  return false;
}

static bool
gimple_types_compatible_p_1 (tree, tree, enum gtc_mode, type_pair_t,
			     VEC(type_pair_t, heap) **,
			     struct pointer_map_t *, struct obstack *);

/* DFS visit the edge from the callers type pair with state *STATE to
   the pair T1, T2 while operating in FOR_MERGING_P mode.
   Update the merging status if it is not part of the SCC containing the
   callers pair and return it.
   SCCSTACK, SCCSTATE and SCCSTATE_OBSTACK are state for the DFS walk done.  */

static bool
gtc_visit (tree t1, tree t2, enum gtc_mode mode,
	   struct sccs *state,
	   VEC(type_pair_t, heap) **sccstack,
	   struct pointer_map_t *sccstate,
	   struct obstack *sccstate_obstack)
{
  struct sccs *cstate = NULL;
  type_pair_t p;
  void **slot;

  /* Check first for the obvious case of pointer identity.  */
  if (t1 == t2)
    return true;

  /* Check that we have two types to compare.  */
  if (t1 == NULL_TREE || t2 == NULL_TREE)
    return false;

  /* If the types have been previously registered and found equal
     they still are.  */
  if (mode == GTC_MERGE)
    {
      tree leader1 = gimple_lookup_type_leader (t1);
      tree leader2 = gimple_lookup_type_leader (t2);
      if (leader1 == t2
	  || t1 == leader2
	  || (leader1 && leader1 == leader2))
	return true;
    }
  else if (mode == GTC_DIAG)
    {
      if (TYPE_CANONICAL (t1)
	  && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
	return true;
    }

  /* Can't be the same type if the types don't have the same code.  */
  if (TREE_CODE (t1) != TREE_CODE (t2))
    return false;

  /* Can't be the same type if they have different CV qualifiers.  */
  if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
    return false;

  /* Void types are always the same.  */
  if (TREE_CODE (t1) == VOID_TYPE)
    return true;

  /* Do some simple checks before doing three hashtable queries.  */
  if (INTEGRAL_TYPE_P (t1)
      || SCALAR_FLOAT_TYPE_P (t1)
      || FIXED_POINT_TYPE_P (t1)
      || TREE_CODE (t1) == VECTOR_TYPE
      || TREE_CODE (t1) == COMPLEX_TYPE
      || TREE_CODE (t1) == OFFSET_TYPE)
    {
      /* Can't be the same type if they have different alignment,
	 sign, precision or mode.  */
      if (TYPE_ALIGN (t1) != TYPE_ALIGN (t2)
	  || TYPE_PRECISION (t1) != TYPE_PRECISION (t2)
	  || TYPE_MODE (t1) != TYPE_MODE (t2)
	  || TYPE_UNSIGNED (t1) != TYPE_UNSIGNED (t2))
	return false;

      if (TREE_CODE (t1) == INTEGER_TYPE
	  && (TYPE_IS_SIZETYPE (t1) != TYPE_IS_SIZETYPE (t2)
	      || TYPE_STRING_FLAG (t1) != TYPE_STRING_FLAG (t2)))
	return false;

      /* That's all we need to check for float and fixed-point types.  */
      if (SCALAR_FLOAT_TYPE_P (t1)
	  || FIXED_POINT_TYPE_P (t1))
	return true;

      /* For integral types fall thru to more complex checks.  */
    }

  else if (AGGREGATE_TYPE_P (t1) || POINTER_TYPE_P (t1))
    {
      /* Can't be the same type if they have different alignment or mode.  */
      if (TYPE_ALIGN (t1) != TYPE_ALIGN (t2)
	  || TYPE_MODE (t1) != TYPE_MODE (t2))
	return false;
    }

  /* If the hash values of t1 and t2 are different the types can't
     possibly be the same.  This helps keeping the type-pair hashtable
     small, only tracking comparisons for hash collisions.  */
  if (gimple_type_hash_1 (t1, mode) != gimple_type_hash_1 (t2, mode))
    return false;

  /* Allocate a new cache entry for this comparison.  */
  p = lookup_type_pair (t1, t2, &gtc_visited, &gtc_ob);
  if (p->same_p[mode] == 0 || p->same_p[mode] == 1)
    {
      /* We have already decided whether T1 and T2 are the
	 same, return the cached result.  */
      return p->same_p[mode] == 1;
    }

  if ((slot = pointer_map_contains (sccstate, p)) != NULL)
    cstate = (struct sccs *)*slot;
  /* Not yet visited.  DFS recurse.  */
  if (!cstate)
    {
      gimple_types_compatible_p_1 (t1, t2, mode, p,
				   sccstack, sccstate, sccstate_obstack);
      cstate = (struct sccs *)* pointer_map_contains (sccstate, p);
      state->low = MIN (state->low, cstate->low);
    }
  /* If the type is still on the SCC stack adjust the parents low.  */
  if (cstate->dfsnum < state->dfsnum
      && cstate->on_sccstack)
    state->low = MIN (cstate->dfsnum, state->low);

  /* Return the current lattice value.  We start with an equality
     assumption so types part of a SCC will be optimistically
     treated equal unless proven otherwise.  */
  return cstate->u.same_p;
}

/* Worker for gimple_types_compatible.
   SCCSTACK, SCCSTATE and SCCSTATE_OBSTACK are state for the DFS walk done.  */

static bool
gimple_types_compatible_p_1 (tree t1, tree t2, enum gtc_mode mode,
			     type_pair_t p,
			     VEC(type_pair_t, heap) **sccstack,
			     struct pointer_map_t *sccstate,
			     struct obstack *sccstate_obstack)
{
  struct sccs *state;

  gcc_assert (p->same_p[mode] == -2);

  state = XOBNEW (sccstate_obstack, struct sccs);
  *pointer_map_insert (sccstate, p) = state;

  VEC_safe_push (type_pair_t, heap, *sccstack, p);
  state->dfsnum = gtc_next_dfs_num++;
  state->low = state->dfsnum;
  state->on_sccstack = true;
  /* Start with an equality assumption.  As we DFS recurse into child
     SCCs this assumption may get revisited.  */
  state->u.same_p = 1;

  /* If their attributes are not the same they can't be the same type.  */
  if (!attribute_list_equal (TYPE_ATTRIBUTES (t1), TYPE_ATTRIBUTES (t2)))
    goto different_types;

  /* Do type-specific comparisons.  */
  switch (TREE_CODE (t1))
    {
    case VECTOR_TYPE:
    case COMPLEX_TYPE:
      if (!gtc_visit (TREE_TYPE (t1), TREE_TYPE (t2), mode,
		      state, sccstack, sccstate, sccstate_obstack))
	goto different_types;
      goto same_types;

    case ARRAY_TYPE:
      /* Array types are the same if the element types are the same and
	 the number of elements are the same.  */
      if (!gtc_visit (TREE_TYPE (t1), TREE_TYPE (t2), mode,
		      state, sccstack, sccstate, sccstate_obstack)
	  || TYPE_STRING_FLAG (t1) != TYPE_STRING_FLAG (t2)
	  || TYPE_NONALIASED_COMPONENT (t1) != TYPE_NONALIASED_COMPONENT (t2))
	goto different_types;
      else
	{
	  tree i1 = TYPE_DOMAIN (t1);
	  tree i2 = TYPE_DOMAIN (t2);

	  /* For an incomplete external array, the type domain can be
 	     NULL_TREE.  Check this condition also.  */
	  if (i1 == NULL_TREE && i2 == NULL_TREE)
	    goto same_types;
	  else if (i1 == NULL_TREE || i2 == NULL_TREE)
	    goto different_types;
	  /* If for a complete array type the possibly gimplified sizes
	     are different the types are different.  */
	  else if (((TYPE_SIZE (i1) != NULL) ^ (TYPE_SIZE (i2) != NULL))
		   || (TYPE_SIZE (i1)
		       && TYPE_SIZE (i2)
		       && !operand_equal_p (TYPE_SIZE (i1), TYPE_SIZE (i2), 0)))
	    goto different_types;
	  else
	    {
	      tree min1 = TYPE_MIN_VALUE (i1);
	      tree min2 = TYPE_MIN_VALUE (i2);
	      tree max1 = TYPE_MAX_VALUE (i1);
	      tree max2 = TYPE_MAX_VALUE (i2);

	      /* The minimum/maximum values have to be the same.  */
	      if ((min1 == min2
		   || (min1 && min2
		       && ((TREE_CODE (min1) == PLACEHOLDER_EXPR
			    && TREE_CODE (min2) == PLACEHOLDER_EXPR)
		           || operand_equal_p (min1, min2, 0))))
		  && (max1 == max2
		      || (max1 && max2
			  && ((TREE_CODE (max1) == PLACEHOLDER_EXPR
			       && TREE_CODE (max2) == PLACEHOLDER_EXPR)
			      || operand_equal_p (max1, max2, 0)))))
		goto same_types;
	      else
		goto different_types;
	    }
	}

    case METHOD_TYPE:
      /* Method types should belong to the same class.  */
      if (!gtc_visit (TYPE_METHOD_BASETYPE (t1), TYPE_METHOD_BASETYPE (t2),
		      mode, state, sccstack, sccstate, sccstate_obstack))
	goto different_types;

      /* Fallthru  */

    case FUNCTION_TYPE:
      /* Function types are the same if the return type and arguments types
	 are the same.  */
      if ((mode != GTC_DIAG
	   || !gimple_compatible_complete_and_incomplete_subtype_p
	         (TREE_TYPE (t1), TREE_TYPE (t2)))
	  && !gtc_visit (TREE_TYPE (t1), TREE_TYPE (t2), mode,
			 state, sccstack, sccstate, sccstate_obstack))
	goto different_types;

      if (!comp_type_attributes (t1, t2))
	goto different_types;

      if (TYPE_ARG_TYPES (t1) == TYPE_ARG_TYPES (t2))
	goto same_types;
      else
	{
	  tree parms1, parms2;

	  for (parms1 = TYPE_ARG_TYPES (t1), parms2 = TYPE_ARG_TYPES (t2);
	       parms1 && parms2;
	       parms1 = TREE_CHAIN (parms1), parms2 = TREE_CHAIN (parms2))
	    {
	      if ((mode == GTC_MERGE
		   || !gimple_compatible_complete_and_incomplete_subtype_p
		         (TREE_VALUE (parms1), TREE_VALUE (parms2)))
		  && !gtc_visit (TREE_VALUE (parms1), TREE_VALUE (parms2), mode,
				 state, sccstack, sccstate, sccstate_obstack))
		goto different_types;
	    }

	  if (parms1 || parms2)
	    goto different_types;

	  goto same_types;
	}

    case OFFSET_TYPE:
      {
	if (!gtc_visit (TREE_TYPE (t1), TREE_TYPE (t2), mode,
			state, sccstack, sccstate, sccstate_obstack)
	    || !gtc_visit (TYPE_OFFSET_BASETYPE (t1),
			   TYPE_OFFSET_BASETYPE (t2), mode,
			   state, sccstack, sccstate, sccstate_obstack))
	  goto different_types;

	goto same_types;
      }

    case POINTER_TYPE:
    case REFERENCE_TYPE:
      {
	/* If the two pointers have different ref-all attributes,
	   they can't be the same type.  */
	if (TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
	  goto different_types;

	/* If one pointer points to an incomplete type variant of
	   the other pointed-to type they are the same.  */
	if (mode == GTC_DIAG
	    && gimple_compatible_complete_and_incomplete_subtype_p
	         (TREE_TYPE (t1), TREE_TYPE (t2)))
	  goto same_types;

	/* Otherwise, pointer and reference types are the same if the
	   pointed-to types are the same.  */
	if (gtc_visit (TREE_TYPE (t1), TREE_TYPE (t2), mode,
		       state, sccstack, sccstate, sccstate_obstack))
	  goto same_types;

	goto different_types;
      }

    case NULLPTR_TYPE:
      /* There is only one decltype(nullptr).  */
      goto same_types;

    case INTEGER_TYPE:
    case BOOLEAN_TYPE:
      {
	tree min1 = TYPE_MIN_VALUE (t1);
	tree max1 = TYPE_MAX_VALUE (t1);
	tree min2 = TYPE_MIN_VALUE (t2);
	tree max2 = TYPE_MAX_VALUE (t2);
	bool min_equal_p = false;
	bool max_equal_p = false;

	/* If either type has a minimum value, the other type must
	   have the same.  */
	if (min1 == NULL_TREE && min2 == NULL_TREE)
	  min_equal_p = true;
	else if (min1 && min2 && operand_equal_p (min1, min2, 0))
	  min_equal_p = true;

	/* Likewise, if either type has a maximum value, the other
	   type must have the same.  */
	if (max1 == NULL_TREE && max2 == NULL_TREE)
	  max_equal_p = true;
	else if (max1 && max2 && operand_equal_p (max1, max2, 0))
	  max_equal_p = true;

	if (!min_equal_p || !max_equal_p)
	  goto different_types;

	goto same_types;
      }

    case ENUMERAL_TYPE:
      {
	/* FIXME lto, we cannot check bounds on enumeral types because
	   different front ends will produce different values.
	   In C, enumeral types are integers, while in C++ each element
	   will have its own symbolic value.  We should decide how enums
	   are to be represented in GIMPLE and have each front end lower
	   to that.  */
	tree v1, v2;

	/* For enumeral types, all the values must be the same.  */
	if (TYPE_VALUES (t1) == TYPE_VALUES (t2))
	  goto same_types;

	for (v1 = TYPE_VALUES (t1), v2 = TYPE_VALUES (t2);
	     v1 && v2;
	     v1 = TREE_CHAIN (v1), v2 = TREE_CHAIN (v2))
	  {
	    tree c1 = TREE_VALUE (v1);
	    tree c2 = TREE_VALUE (v2);

	    if (TREE_CODE (c1) == CONST_DECL)
	      c1 = DECL_INITIAL (c1);

	    if (TREE_CODE (c2) == CONST_DECL)
	      c2 = DECL_INITIAL (c2);

	    if (tree_int_cst_equal (c1, c2) != 1)
	      goto different_types;
	  }

	/* If one enumeration has more values than the other, they
	   are not the same.  */
	if (v1 || v2)
	  goto different_types;

	goto same_types;
      }

    case RECORD_TYPE:
    case UNION_TYPE:
    case QUAL_UNION_TYPE:
      {
	tree f1, f2;

	/* The struct tags shall compare equal.  */
	if (mode == GTC_MERGE
	    && !compare_type_names_p (TYPE_MAIN_VARIANT (t1),
				      TYPE_MAIN_VARIANT (t2), false))
	  goto different_types;

	/* For aggregate types, all the fields must be the same.  */
	for (f1 = TYPE_FIELDS (t1), f2 = TYPE_FIELDS (t2);
	     f1 && f2;
	     f1 = TREE_CHAIN (f1), f2 = TREE_CHAIN (f2))
	  {
	    /* The fields must have the same name, offset and type.  */
	    if ((mode == GTC_MERGE
		 && DECL_NAME (f1) != DECL_NAME (f2))
		|| DECL_NONADDRESSABLE_P (f1) != DECL_NONADDRESSABLE_P (f2)
		|| !gimple_compare_field_offset (f1, f2)
		|| !gtc_visit (TREE_TYPE (f1), TREE_TYPE (f2), mode,
			       state, sccstack, sccstate, sccstate_obstack))
	      goto different_types;
	  }

	/* If one aggregate has more fields than the other, they
	   are not the same.  */
	if (f1 || f2)
	  goto different_types;

	goto same_types;
      }

    default:
      gcc_unreachable ();
    }

  /* Common exit path for types that are not compatible.  */
different_types:
  state->u.same_p = 0;
  goto pop;

  /* Common exit path for types that are compatible.  */
same_types:
  gcc_assert (state->u.same_p == 1);

pop:
  if (state->low == state->dfsnum)
    {
      type_pair_t x;

      /* Pop off the SCC and set its cache values to the final
         comparison result.  */
      do
	{
	  struct sccs *cstate;
	  x = VEC_pop (type_pair_t, *sccstack);
	  cstate = (struct sccs *)*pointer_map_contains (sccstate, x);
	  cstate->on_sccstack = false;
	  x->same_p[mode] = state->u.same_p;
	}
      while (x != p);
    }

  return state->u.same_p;
}

/* Return true iff T1 and T2 are structurally identical.  When
   FOR_MERGING_P is true the an incomplete type and a complete type
   are considered different, otherwise they are considered compatible.  */

bool
gimple_types_compatible_p (tree t1, tree t2, enum gtc_mode mode)
{
  VEC(type_pair_t, heap) *sccstack = NULL;
  struct pointer_map_t *sccstate;
  struct obstack sccstate_obstack;
  type_pair_t p = NULL;
  bool res;

  /* Before starting to set up the SCC machinery handle simple cases.  */

  /* Check first for the obvious case of pointer identity.  */
  if (t1 == t2)
    return true;

  /* Check that we have two types to compare.  */
  if (t1 == NULL_TREE || t2 == NULL_TREE)
    return false;

  /* If the types have been previously registered and found equal
     they still are.  */
  if (mode == GTC_MERGE)
    {
      tree leader1 = gimple_lookup_type_leader (t1);
      tree leader2 = gimple_lookup_type_leader (t2);
      if (leader1 == t2
	  || t1 == leader2
	  || (leader1 && leader1 == leader2))
	return true;
    }
  else if (mode == GTC_DIAG)
    {
      if (TYPE_CANONICAL (t1)
	  && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
	return true;
    }

  /* Can't be the same type if the types don't have the same code.  */
  if (TREE_CODE (t1) != TREE_CODE (t2))
    return false;

  /* Can't be the same type if they have different CV qualifiers.  */
  if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
    return false;

  /* Void types are always the same.  */
  if (TREE_CODE (t1) == VOID_TYPE)
    return true;

  /* Do some simple checks before doing three hashtable queries.  */
  if (INTEGRAL_TYPE_P (t1)
      || SCALAR_FLOAT_TYPE_P (t1)
      || FIXED_POINT_TYPE_P (t1)
      || TREE_CODE (t1) == VECTOR_TYPE
      || TREE_CODE (t1) == COMPLEX_TYPE
      || TREE_CODE (t1) == OFFSET_TYPE)
    {
      /* Can't be the same type if they have different alignment,
	 sign, precision or mode.  */
      if (TYPE_ALIGN (t1) != TYPE_ALIGN (t2)
	  || TYPE_PRECISION (t1) != TYPE_PRECISION (t2)
	  || TYPE_MODE (t1) != TYPE_MODE (t2)
	  || TYPE_UNSIGNED (t1) != TYPE_UNSIGNED (t2))
	return false;

      if (TREE_CODE (t1) == INTEGER_TYPE
	  && (TYPE_IS_SIZETYPE (t1) != TYPE_IS_SIZETYPE (t2)
	      || TYPE_STRING_FLAG (t1) != TYPE_STRING_FLAG (t2)))
	return false;

      /* That's all we need to check for float and fixed-point types.  */
      if (SCALAR_FLOAT_TYPE_P (t1)
	  || FIXED_POINT_TYPE_P (t1))
	return true;

      /* For integral types fall thru to more complex checks.  */
    }

  else if (AGGREGATE_TYPE_P (t1) || POINTER_TYPE_P (t1))
    {
      /* Can't be the same type if they have different alignment or mode.  */
      if (TYPE_ALIGN (t1) != TYPE_ALIGN (t2)
	  || TYPE_MODE (t1) != TYPE_MODE (t2))
	return false;
    }

  /* If the hash values of t1 and t2 are different the types can't
     possibly be the same.  This helps keeping the type-pair hashtable
     small, only tracking comparisons for hash collisions.  */
  if (gimple_type_hash_1 (t1, mode) != gimple_type_hash_1 (t2, mode))
    return false;

  /* If we've visited this type pair before (in the case of aggregates
     with self-referential types), and we made a decision, return it.  */
  p = lookup_type_pair (t1, t2, &gtc_visited, &gtc_ob);
  if (p->same_p[mode] == 0 || p->same_p[mode] == 1)
    {
      /* We have already decided whether T1 and T2 are the
	 same, return the cached result.  */
      return p->same_p[mode] == 1;
    }

  /* Now set up the SCC machinery for the comparison.  */
  gtc_next_dfs_num = 1;
  sccstate = pointer_map_create ();
  gcc_obstack_init (&sccstate_obstack);
  res = gimple_types_compatible_p_1 (t1, t2, mode, p,
				     &sccstack, sccstate, &sccstate_obstack);
  VEC_free (type_pair_t, heap, sccstack);
  pointer_map_destroy (sccstate);
  obstack_free (&sccstate_obstack, NULL);

  return res;
}


static hashval_t
iterative_hash_gimple_type (tree, hashval_t, VEC(tree, heap) **,
			    struct pointer_map_t *, struct obstack *,
			    enum gtc_mode);

/* DFS visit the edge from the callers type with state *STATE to T.
   Update the callers type hash V with the hash for T if it is not part
   of the SCC containing the callers type and return it.
   SCCSTACK, SCCSTATE and SCCSTATE_OBSTACK are state for the DFS walk done.  */

static hashval_t
visit (tree t, struct sccs *state, hashval_t v,
       VEC (tree, heap) **sccstack,
       struct pointer_map_t *sccstate,
       struct obstack *sccstate_obstack, enum gtc_mode mode)
{
  struct sccs *cstate = NULL;
  struct tree_int_map m;
  void **slot;

  /* If there is a hash value recorded for this type then it can't
     possibly be part of our parent SCC.  Simply mix in its hash.  */
  m.base.from = t;
  if ((slot = htab_find_slot (mode == GTC_MERGE
			      ? type_hash_cache : canonical_type_hash_cache,
			      &m, NO_INSERT))
      && *slot)
    return iterative_hash_hashval_t (((struct tree_int_map *) *slot)->to, v);

  if ((slot = pointer_map_contains (sccstate, t)) != NULL)
    cstate = (struct sccs *)*slot;
  if (!cstate)
    {
      hashval_t tem;
      /* Not yet visited.  DFS recurse.  */
      tem = iterative_hash_gimple_type (t, v,
					sccstack, sccstate, sccstate_obstack,
					mode);
      if (!cstate)
	cstate = (struct sccs *)* pointer_map_contains (sccstate, t);
      state->low = MIN (state->low, cstate->low);
      /* If the type is no longer on the SCC stack and thus is not part
         of the parents SCC mix in its hash value.  Otherwise we will
	 ignore the type for hashing purposes and return the unaltered
	 hash value.  */
      if (!cstate->on_sccstack)
	return tem;
    }
  if (cstate->dfsnum < state->dfsnum
      && cstate->on_sccstack)
    state->low = MIN (cstate->dfsnum, state->low);

  /* We are part of our parents SCC, skip this type during hashing
     and return the unaltered hash value.  */
  return v;
}

/* Hash NAME with the previous hash value V and return it.  */

static hashval_t
iterative_hash_name (tree name, hashval_t v)
{
  if (!name)
    return v;
  if (TREE_CODE (name) == TYPE_DECL)
    name = DECL_NAME (name);
  if (!name)
    return v;
  gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE);
  return iterative_hash_object (IDENTIFIER_HASH_VALUE (name), v);
}

/* Returning a hash value for gimple type TYPE combined with VAL.
   SCCSTACK, SCCSTATE and SCCSTATE_OBSTACK are state for the DFS walk done.

   To hash a type we end up hashing in types that are reachable.
   Through pointers we can end up with cycles which messes up the
   required property that we need to compute the same hash value
   for structurally equivalent types.  To avoid this we have to
   hash all types in a cycle (the SCC) in a commutative way.  The
   easiest way is to not mix in the hashes of the SCC members at
   all.  To make this work we have to delay setting the hash
   values of the SCC until it is complete.  */

static hashval_t
iterative_hash_gimple_type (tree type, hashval_t val,
			    VEC(tree, heap) **sccstack,
			    struct pointer_map_t *sccstate,
			    struct obstack *sccstate_obstack,
			    enum gtc_mode mode)
{
  hashval_t v;
  void **slot;
  struct sccs *state;

  /* Not visited during this DFS walk.  */
  gcc_checking_assert (!pointer_map_contains (sccstate, type));
  state = XOBNEW (sccstate_obstack, struct sccs);
  *pointer_map_insert (sccstate, type) = state;

  VEC_safe_push (tree, heap, *sccstack, type);
  state->dfsnum = next_dfs_num++;
  state->low = state->dfsnum;
  state->on_sccstack = true;

  /* Combine a few common features of types so that types are grouped into
     smaller sets; when searching for existing matching types to merge,
     only existing types having the same features as the new type will be
     checked.  */
  v = iterative_hash_hashval_t (TREE_CODE (type), 0);
  v = iterative_hash_hashval_t (TYPE_QUALS (type), v);
  v = iterative_hash_hashval_t (TREE_ADDRESSABLE (type), v);

  /* Do not hash the types size as this will cause differences in
     hash values for the complete vs. the incomplete type variant.  */

  /* Incorporate common features of numerical types.  */
  if (INTEGRAL_TYPE_P (type)
      || SCALAR_FLOAT_TYPE_P (type)
      || FIXED_POINT_TYPE_P (type))
    {
      v = iterative_hash_hashval_t (TYPE_PRECISION (type), v);
      v = iterative_hash_hashval_t (TYPE_MODE (type), v);
      v = iterative_hash_hashval_t (TYPE_UNSIGNED (type), v);
    }

  /* For pointer and reference types, fold in information about the type
     pointed to but do not recurse into possibly incomplete types to
     avoid hash differences for complete vs. incomplete types.  */
  if (POINTER_TYPE_P (type))
    {
      if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (type)))
	{
	  v = iterative_hash_hashval_t (TREE_CODE (TREE_TYPE (type)), v);
	  v = iterative_hash_name
		(TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (type))), v);
	}
      else
	v = visit (TREE_TYPE (type), state, v,
		   sccstack, sccstate, sccstate_obstack, mode);
    }

  /* For integer types hash the types min/max values and the string flag.  */
  if (TREE_CODE (type) == INTEGER_TYPE)
    {
      /* OMP lowering can introduce error_mark_node in place of
	 random local decls in types.  */
      if (TYPE_MIN_VALUE (type) != error_mark_node)
	v = iterative_hash_expr (TYPE_MIN_VALUE (type), v);
      if (TYPE_MAX_VALUE (type) != error_mark_node)
	v = iterative_hash_expr (TYPE_MAX_VALUE (type), v);
      v = iterative_hash_hashval_t (TYPE_STRING_FLAG (type), v);
    }

  /* For array types hash their domain and the string flag.  */
  if (TREE_CODE (type) == ARRAY_TYPE
      && TYPE_DOMAIN (type))
    {
      v = iterative_hash_hashval_t (TYPE_STRING_FLAG (type), v);
      v = visit (TYPE_DOMAIN (type), state, v,
		 sccstack, sccstate, sccstate_obstack, mode);
    }

  /* Recurse for aggregates with a single element type.  */
  if (TREE_CODE (type) == ARRAY_TYPE
      || TREE_CODE (type) == COMPLEX_TYPE
      || TREE_CODE (type) == VECTOR_TYPE)
    v = visit (TREE_TYPE (type), state, v,
	       sccstack, sccstate, sccstate_obstack, mode);

  /* Incorporate function return and argument types.  */
  if (TREE_CODE (type) == FUNCTION_TYPE || TREE_CODE (type) == METHOD_TYPE)
    {
      unsigned na;
      tree p;

      /* For method types also incorporate their parent class.  */
      if (TREE_CODE (type) == METHOD_TYPE)
	v = visit (TYPE_METHOD_BASETYPE (type), state, v,
		   sccstack, sccstate, sccstate_obstack, mode);

      /* For result types allow mismatch in completeness.  */
      if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (type)))
	{
	  v = iterative_hash_hashval_t (TREE_CODE (TREE_TYPE (type)), v);
	  v = iterative_hash_name
		(TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (type))), v);
	}
      else
	v = visit (TREE_TYPE (type), state, v,
		   sccstack, sccstate, sccstate_obstack, mode);

      for (p = TYPE_ARG_TYPES (type), na = 0; p; p = TREE_CHAIN (p))
	{
	  /* For argument types allow mismatch in completeness.  */
	  if (RECORD_OR_UNION_TYPE_P (TREE_VALUE (p)))
	    {
	      v = iterative_hash_hashval_t (TREE_CODE (TREE_VALUE (p)), v);
	      v = iterative_hash_name
		    (TYPE_NAME (TYPE_MAIN_VARIANT (TREE_VALUE (p))), v);
	    }
	  else
	    v = visit (TREE_VALUE (p), state, v,
		       sccstack, sccstate, sccstate_obstack, mode);
	  na++;
	}

      v = iterative_hash_hashval_t (na, v);
    }

  if (TREE_CODE (type) == RECORD_TYPE
      || TREE_CODE (type) == UNION_TYPE
      || TREE_CODE (type) == QUAL_UNION_TYPE)
    {
      unsigned nf;
      tree f;

      if (mode == GTC_MERGE)
	v = iterative_hash_name (TYPE_NAME (TYPE_MAIN_VARIANT (type)), v);

      for (f = TYPE_FIELDS (type), nf = 0; f; f = TREE_CHAIN (f))
	{
	  if (mode == GTC_MERGE)
	    v = iterative_hash_name (DECL_NAME (f), v);
	  v = visit (TREE_TYPE (f), state, v,
		     sccstack, sccstate, sccstate_obstack, mode);
	  nf++;
	}

      v = iterative_hash_hashval_t (nf, v);
    }

  /* Record hash for us.  */
  state->u.hash = v;

  /* See if we found an SCC.  */
  if (state->low == state->dfsnum)
    {
      tree x;

      /* Pop off the SCC and set its hash values.  */
      do
	{
	  struct sccs *cstate;
	  struct tree_int_map *m = ggc_alloc_cleared_tree_int_map ();
	  x = VEC_pop (tree, *sccstack);
	  cstate = (struct sccs *)*pointer_map_contains (sccstate, x);
	  cstate->on_sccstack = false;
	  m->base.from = x;
	  m->to = cstate->u.hash;
	  slot = htab_find_slot (mode == GTC_MERGE
				 ? type_hash_cache : canonical_type_hash_cache,
				 m, INSERT);
	  gcc_assert (!*slot);
	  *slot = (void *) m;
	}
      while (x != type);
    }

  return iterative_hash_hashval_t (v, val);
}


/* Returns a hash value for P (assumed to be a type).  The hash value
   is computed using some distinguishing features of the type.  Note
   that we cannot use pointer hashing here as we may be dealing with
   two distinct instances of the same type.

   This function should produce the same hash value for two compatible
   types according to gimple_types_compatible_p.  */

static hashval_t
gimple_type_hash_1 (const void *p, enum gtc_mode mode)
{
  const_tree t = (const_tree) p;
  VEC(tree, heap) *sccstack = NULL;
  struct pointer_map_t *sccstate;
  struct obstack sccstate_obstack;
  hashval_t val;
  void **slot;
  struct tree_int_map m;

  if (mode == GTC_MERGE
      && type_hash_cache == NULL)
    type_hash_cache = htab_create_ggc (512, tree_int_map_hash,
				       tree_int_map_eq, NULL);
  else if (mode == GTC_DIAG
	   && canonical_type_hash_cache == NULL)
    canonical_type_hash_cache = htab_create_ggc (512, tree_int_map_hash,
						 tree_int_map_eq, NULL);

  m.base.from = CONST_CAST_TREE (t);
  if ((slot = htab_find_slot (mode == GTC_MERGE
			      ? type_hash_cache : canonical_type_hash_cache,
			      &m, NO_INSERT))
      && *slot)
    return iterative_hash_hashval_t (((struct tree_int_map *) *slot)->to, 0);

  /* Perform a DFS walk and pre-hash all reachable types.  */
  next_dfs_num = 1;
  sccstate = pointer_map_create ();
  gcc_obstack_init (&sccstate_obstack);
  val = iterative_hash_gimple_type (CONST_CAST_TREE (t), 0,
				    &sccstack, sccstate, &sccstate_obstack,
				    mode);
  VEC_free (tree, heap, sccstack);
  pointer_map_destroy (sccstate);
  obstack_free (&sccstate_obstack, NULL);

  return val;
}

static hashval_t
gimple_type_hash (const void *p)
{
  return gimple_type_hash_1 (p, GTC_MERGE);
}

static hashval_t
gimple_canonical_type_hash (const void *p)
{
  return gimple_type_hash_1 (p, GTC_DIAG);
}


/* Returns nonzero if P1 and P2 are equal.  */

static int
gimple_type_eq (const void *p1, const void *p2)
{
  const_tree t1 = (const_tree) p1;
  const_tree t2 = (const_tree) p2;
  return gimple_types_compatible_p (CONST_CAST_TREE (t1),
				    CONST_CAST_TREE (t2), GTC_MERGE);
}


/* Register type T in the global type table gimple_types.
   If another type T', compatible with T, already existed in
   gimple_types then return T', otherwise return T.  This is used by
   LTO to merge identical types read from different TUs.  */

tree
gimple_register_type (tree t)
{
  void **slot;
  gimple_type_leader_entry *leader;
  tree mv_leader = NULL_TREE;

  gcc_assert (TYPE_P (t));

  if (!gimple_type_leader)
    gimple_type_leader = ggc_alloc_cleared_vec_gimple_type_leader_entry_s
				(GIMPLE_TYPE_LEADER_SIZE);
  /* If we registered this type before return the cached result.  */
  leader = &gimple_type_leader[TYPE_UID (t) % GIMPLE_TYPE_LEADER_SIZE];
  if (leader->type == t)
    return leader->leader;

  /* Always register the main variant first.  This is important so we
     pick up the non-typedef variants as canonical, otherwise we'll end
     up taking typedef ids for structure tags during comparison.  */
  if (TYPE_MAIN_VARIANT (t) != t)
    mv_leader = gimple_register_type (TYPE_MAIN_VARIANT (t));

  if (gimple_types == NULL)
    gimple_types = htab_create_ggc (16381, gimple_type_hash, gimple_type_eq, 0);

  slot = htab_find_slot (gimple_types, t, INSERT);
  if (*slot
      && *(tree *)slot != t)
    {
      tree new_type = (tree) *((tree *) slot);

      /* Do not merge types with different addressability.  */
      gcc_assert (TREE_ADDRESSABLE (t) == TREE_ADDRESSABLE (new_type));

      /* If t is not its main variant then make t unreachable from its
	 main variant list.  Otherwise we'd queue up a lot of duplicates
	 there.  */
      if (t != TYPE_MAIN_VARIANT (t))
	{
	  tree tem = TYPE_MAIN_VARIANT (t);
	  while (tem && TYPE_NEXT_VARIANT (tem) != t)
	    tem = TYPE_NEXT_VARIANT (tem);
	  if (tem)
	    TYPE_NEXT_VARIANT (tem) = TYPE_NEXT_VARIANT (t);
	  TYPE_NEXT_VARIANT (t) = NULL_TREE;
	}

      /* If we are a pointer then remove us from the pointer-to or
	 reference-to chain.  Otherwise we'd queue up a lot of duplicates
	 there.  */
      if (TREE_CODE (t) == POINTER_TYPE)
	{
	  if (TYPE_POINTER_TO (TREE_TYPE (t)) == t)
	    TYPE_POINTER_TO (TREE_TYPE (t)) = TYPE_NEXT_PTR_TO (t);
	  else
	    {
	      tree tem = TYPE_POINTER_TO (TREE_TYPE (t));
	      while (tem && TYPE_NEXT_PTR_TO (tem) != t)
		tem = TYPE_NEXT_PTR_TO (tem);
	      if (tem)
		TYPE_NEXT_PTR_TO (tem) = TYPE_NEXT_PTR_TO (t);
	    }
	  TYPE_NEXT_PTR_TO (t) = NULL_TREE;
	}
      else if (TREE_CODE (t) == REFERENCE_TYPE)
	{
	  if (TYPE_REFERENCE_TO (TREE_TYPE (t)) == t)
	    TYPE_REFERENCE_TO (TREE_TYPE (t)) = TYPE_NEXT_REF_TO (t);
	  else
	    {
	      tree tem = TYPE_REFERENCE_TO (TREE_TYPE (t));
	      while (tem && TYPE_NEXT_REF_TO (tem) != t)
		tem = TYPE_NEXT_REF_TO (tem);
	      if (tem)
		TYPE_NEXT_REF_TO (tem) = TYPE_NEXT_REF_TO (t);
	    }
	  TYPE_NEXT_REF_TO (t) = NULL_TREE;
	}

      leader->type = t;
      leader->leader = new_type;
      t = new_type;
    }
  else
    {
      leader->type = t;
      leader->leader = t;
      /* We're the type leader.  Make our TYPE_MAIN_VARIANT valid.  */
      if (TYPE_MAIN_VARIANT (t) != t
	  && TYPE_MAIN_VARIANT (t) != mv_leader)
	{
	  /* Remove us from our main variant list as we are not the variant
	     leader and the variant leader will change.  */
	  tree tem = TYPE_MAIN_VARIANT (t);
	  while (tem && TYPE_NEXT_VARIANT (tem) != t)
	    tem = TYPE_NEXT_VARIANT (tem);
	  if (tem)
	    TYPE_NEXT_VARIANT (tem) = TYPE_NEXT_VARIANT (t);
	  TYPE_NEXT_VARIANT (t) = NULL_TREE;
	  /* Adjust our main variant.  Linking us into its variant list
	     will happen at fixup time.  */
	  TYPE_MAIN_VARIANT (t) = mv_leader;
	}
      *slot = (void *) t;
    }

  return t;
}


/* Returns nonzero if P1 and P2 are equal.  */

static int
gimple_canonical_type_eq (const void *p1, const void *p2)
{
  const_tree t1 = (const_tree) p1;
  const_tree t2 = (const_tree) p2;
  return gimple_types_compatible_p (CONST_CAST_TREE (t1),
				    CONST_CAST_TREE (t2), GTC_DIAG);
}

/* Register type T in the global type table gimple_types.
   If another type T', compatible with T, already existed in
   gimple_types then return T', otherwise return T.  This is used by
   LTO to merge identical types read from different TUs.  */

tree
gimple_register_canonical_type (tree t)
{
  void **slot;
  tree orig_t = t;

  gcc_assert (TYPE_P (t));

  if (TYPE_CANONICAL (t))
    return TYPE_CANONICAL (t);

  /* Always register the type itself first so that if it turns out
     to be the canonical type it will be the one we merge to as well.  */
  t = gimple_register_type (t);

  /* Always register the main variant first.  This is important so we
     pick up the non-typedef variants as canonical, otherwise we'll end
     up taking typedef ids for structure tags during comparison.  */
  if (TYPE_MAIN_VARIANT (t) != t)
    gimple_register_canonical_type (TYPE_MAIN_VARIANT (t));

  if (gimple_canonical_types == NULL)
    gimple_canonical_types = htab_create_ggc (16381, gimple_canonical_type_hash,
					      gimple_canonical_type_eq, 0);

  slot = htab_find_slot (gimple_canonical_types, t, INSERT);
  if (*slot
      && *(tree *)slot != t)
    {
      tree new_type = (tree) *((tree *) slot);

      TYPE_CANONICAL (t) = new_type;
      t = new_type;
    }
  else
    {
      TYPE_CANONICAL (t) = t;
      *slot = (void *) t;
    }

  /* Also cache the canonical type in the non-leaders.  */
  TYPE_CANONICAL (orig_t) = t;

  return t;
}


/* Show statistics on references to the global type table gimple_types.  */

void
print_gimple_types_stats (void)
{
  if (gimple_types)
    fprintf (stderr, "GIMPLE type table: size %ld, %ld elements, "
	     "%ld searches, %ld collisions (ratio: %f)\n",
	     (long) htab_size (gimple_types),
	     (long) htab_elements (gimple_types),
	     (long) gimple_types->searches,
	     (long) gimple_types->collisions,
	     htab_collisions (gimple_types));
  else
    fprintf (stderr, "GIMPLE type table is empty\n");
  if (type_hash_cache)
    fprintf (stderr, "GIMPLE type hash table: size %ld, %ld elements, "
	     "%ld searches, %ld collisions (ratio: %f)\n",
	     (long) htab_size (type_hash_cache),
	     (long) htab_elements (type_hash_cache),
	     (long) type_hash_cache->searches,
	     (long) type_hash_cache->collisions,
	     htab_collisions (type_hash_cache));
  else
    fprintf (stderr, "GIMPLE type hash table is empty\n");
  if (gimple_canonical_types)
    fprintf (stderr, "GIMPLE canonical type table: size %ld, %ld elements, "
	     "%ld searches, %ld collisions (ratio: %f)\n",
	     (long) htab_size (gimple_canonical_types),
	     (long) htab_elements (gimple_canonical_types),
	     (long) gimple_canonical_types->searches,
	     (long) gimple_canonical_types->collisions,
	     htab_collisions (gimple_canonical_types));
  else
    fprintf (stderr, "GIMPLE canonical type table is empty\n");
  if (canonical_type_hash_cache)
    fprintf (stderr, "GIMPLE canonical type hash table: size %ld, %ld elements, "
	     "%ld searches, %ld collisions (ratio: %f)\n",
	     (long) htab_size (canonical_type_hash_cache),
	     (long) htab_elements (canonical_type_hash_cache),
	     (long) canonical_type_hash_cache->searches,
	     (long) canonical_type_hash_cache->collisions,
	     htab_collisions (canonical_type_hash_cache));
  else
    fprintf (stderr, "GIMPLE canonical type hash table is empty\n");
  if (gtc_visited)
    fprintf (stderr, "GIMPLE type comparison table: size %ld, %ld "
	     "elements, %ld searches, %ld collisions (ratio: %f)\n",
	     (long) htab_size (gtc_visited),
	     (long) htab_elements (gtc_visited),
	     (long) gtc_visited->searches,
	     (long) gtc_visited->collisions,
	     htab_collisions (gtc_visited));
  else
    fprintf (stderr, "GIMPLE type comparison table is empty\n");
}

/* Free the gimple type hashtables used for LTO type merging.  */

void
free_gimple_type_tables (void)
{
  /* Last chance to print stats for the tables.  */
  if (flag_lto_report)
    print_gimple_types_stats ();

  if (gimple_types)
    {
      htab_delete (gimple_types);
      gimple_types = NULL;
    }
  if (gimple_canonical_types)
    {
      htab_delete (gimple_canonical_types);
      gimple_canonical_types = NULL;
    }
  if (type_hash_cache)
    {
      htab_delete (type_hash_cache);
      type_hash_cache = NULL;
    }
  if (canonical_type_hash_cache)
    {
      htab_delete (canonical_type_hash_cache);
      canonical_type_hash_cache = NULL;
    }
  if (gtc_visited)
    {
      htab_delete (gtc_visited);
      obstack_free (&gtc_ob, NULL);
      gtc_visited = NULL;
    }
  gimple_type_leader = NULL;
}


/* Return a type the same as TYPE except unsigned or
   signed according to UNSIGNEDP.  */

static tree
gimple_signed_or_unsigned_type (bool unsignedp, tree type)
{
  tree type1;

  type1 = TYPE_MAIN_VARIANT (type);
  if (type1 == signed_char_type_node
      || type1 == char_type_node
      || type1 == unsigned_char_type_node)
    return unsignedp ? unsigned_char_type_node : signed_char_type_node;
  if (type1 == integer_type_node || type1 == unsigned_type_node)
    return unsignedp ? unsigned_type_node : integer_type_node;
  if (type1 == short_integer_type_node || type1 == short_unsigned_type_node)
    return unsignedp ? short_unsigned_type_node : short_integer_type_node;
  if (type1 == long_integer_type_node || type1 == long_unsigned_type_node)
    return unsignedp ? long_unsigned_type_node : long_integer_type_node;
  if (type1 == long_long_integer_type_node
      || type1 == long_long_unsigned_type_node)
    return unsignedp
           ? long_long_unsigned_type_node
	   : long_long_integer_type_node;
  if (int128_integer_type_node && (type1 == int128_integer_type_node || type1 == int128_unsigned_type_node))
    return unsignedp
           ? int128_unsigned_type_node
	   : int128_integer_type_node;
#if HOST_BITS_PER_WIDE_INT >= 64
  if (type1 == intTI_type_node || type1 == unsigned_intTI_type_node)
    return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
#endif
  if (type1 == intDI_type_node || type1 == unsigned_intDI_type_node)
    return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
  if (type1 == intSI_type_node || type1 == unsigned_intSI_type_node)
    return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
  if (type1 == intHI_type_node || type1 == unsigned_intHI_type_node)
    return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
  if (type1 == intQI_type_node || type1 == unsigned_intQI_type_node)
    return unsignedp ? unsigned_intQI_type_node : intQI_type_node;

#define GIMPLE_FIXED_TYPES(NAME)	    \
  if (type1 == short_ ## NAME ## _type_node \
      || type1 == unsigned_short_ ## NAME ## _type_node) \
    return unsignedp ? unsigned_short_ ## NAME ## _type_node \
		     : short_ ## NAME ## _type_node; \
  if (type1 == NAME ## _type_node \
      || type1 == unsigned_ ## NAME ## _type_node) \
    return unsignedp ? unsigned_ ## NAME ## _type_node \
		     : NAME ## _type_node; \
  if (type1 == long_ ## NAME ## _type_node \
      || type1 == unsigned_long_ ## NAME ## _type_node) \
    return unsignedp ? unsigned_long_ ## NAME ## _type_node \
		     : long_ ## NAME ## _type_node; \
  if (type1 == long_long_ ## NAME ## _type_node \
      || type1 == unsigned_long_long_ ## NAME ## _type_node) \
    return unsignedp ? unsigned_long_long_ ## NAME ## _type_node \
		     : long_long_ ## NAME ## _type_node;

#define GIMPLE_FIXED_MODE_TYPES(NAME) \
  if (type1 == NAME ## _type_node \
      || type1 == u ## NAME ## _type_node) \
    return unsignedp ? u ## NAME ## _type_node \
		     : NAME ## _type_node;

#define GIMPLE_FIXED_TYPES_SAT(NAME) \
  if (type1 == sat_ ## short_ ## NAME ## _type_node \
      || type1 == sat_ ## unsigned_short_ ## NAME ## _type_node) \
    return unsignedp ? sat_ ## unsigned_short_ ## NAME ## _type_node \
		     : sat_ ## short_ ## NAME ## _type_node; \
  if (type1 == sat_ ## NAME ## _type_node \
      || type1 == sat_ ## unsigned_ ## NAME ## _type_node) \
    return unsignedp ? sat_ ## unsigned_ ## NAME ## _type_node \
		     : sat_ ## NAME ## _type_node; \
  if (type1 == sat_ ## long_ ## NAME ## _type_node \
      || type1 == sat_ ## unsigned_long_ ## NAME ## _type_node) \
    return unsignedp ? sat_ ## unsigned_long_ ## NAME ## _type_node \
		     : sat_ ## long_ ## NAME ## _type_node; \
  if (type1 == sat_ ## long_long_ ## NAME ## _type_node \
      || type1 == sat_ ## unsigned_long_long_ ## NAME ## _type_node) \
    return unsignedp ? sat_ ## unsigned_long_long_ ## NAME ## _type_node \
		     : sat_ ## long_long_ ## NAME ## _type_node;

#define GIMPLE_FIXED_MODE_TYPES_SAT(NAME)	\
  if (type1 == sat_ ## NAME ## _type_node \
      || type1 == sat_ ## u ## NAME ## _type_node) \
    return unsignedp ? sat_ ## u ## NAME ## _type_node \
		     : sat_ ## NAME ## _type_node;

  GIMPLE_FIXED_TYPES (fract);
  GIMPLE_FIXED_TYPES_SAT (fract);
  GIMPLE_FIXED_TYPES (accum);
  GIMPLE_FIXED_TYPES_SAT (accum);

  GIMPLE_FIXED_MODE_TYPES (qq);
  GIMPLE_FIXED_MODE_TYPES (hq);
  GIMPLE_FIXED_MODE_TYPES (sq);
  GIMPLE_FIXED_MODE_TYPES (dq);
  GIMPLE_FIXED_MODE_TYPES (tq);
  GIMPLE_FIXED_MODE_TYPES_SAT (qq);
  GIMPLE_FIXED_MODE_TYPES_SAT (hq);
  GIMPLE_FIXED_MODE_TYPES_SAT (sq);
  GIMPLE_FIXED_MODE_TYPES_SAT (dq);
  GIMPLE_FIXED_MODE_TYPES_SAT (tq);
  GIMPLE_FIXED_MODE_TYPES (ha);
  GIMPLE_FIXED_MODE_TYPES (sa);
  GIMPLE_FIXED_MODE_TYPES (da);
  GIMPLE_FIXED_MODE_TYPES (ta);
  GIMPLE_FIXED_MODE_TYPES_SAT (ha);
  GIMPLE_FIXED_MODE_TYPES_SAT (sa);
  GIMPLE_FIXED_MODE_TYPES_SAT (da);
  GIMPLE_FIXED_MODE_TYPES_SAT (ta);

  /* For ENUMERAL_TYPEs in C++, must check the mode of the types, not
     the precision; they have precision set to match their range, but
     may use a wider mode to match an ABI.  If we change modes, we may
     wind up with bad conversions.  For INTEGER_TYPEs in C, must check
     the precision as well, so as to yield correct results for
     bit-field types.  C++ does not have these separate bit-field
     types, and producing a signed or unsigned variant of an
     ENUMERAL_TYPE may cause other problems as well.  */
  if (!INTEGRAL_TYPE_P (type)
      || TYPE_UNSIGNED (type) == unsignedp)
    return type;

#define TYPE_OK(node)							    \
  (TYPE_MODE (type) == TYPE_MODE (node)					    \
   && TYPE_PRECISION (type) == TYPE_PRECISION (node))
  if (TYPE_OK (signed_char_type_node))
    return unsignedp ? unsigned_char_type_node : signed_char_type_node;
  if (TYPE_OK (integer_type_node))
    return unsignedp ? unsigned_type_node : integer_type_node;
  if (TYPE_OK (short_integer_type_node))
    return unsignedp ? short_unsigned_type_node : short_integer_type_node;
  if (TYPE_OK (long_integer_type_node))
    return unsignedp ? long_unsigned_type_node : long_integer_type_node;
  if (TYPE_OK (long_long_integer_type_node))
    return (unsignedp
	    ? long_long_unsigned_type_node
	    : long_long_integer_type_node);
  if (int128_integer_type_node && TYPE_OK (int128_integer_type_node))
    return (unsignedp
	    ? int128_unsigned_type_node
	    : int128_integer_type_node);

#if HOST_BITS_PER_WIDE_INT >= 64
  if (TYPE_OK (intTI_type_node))
    return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
#endif
  if (TYPE_OK (intDI_type_node))
    return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
  if (TYPE_OK (intSI_type_node))
    return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
  if (TYPE_OK (intHI_type_node))
    return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
  if (TYPE_OK (intQI_type_node))
    return unsignedp ? unsigned_intQI_type_node : intQI_type_node;

#undef GIMPLE_FIXED_TYPES
#undef GIMPLE_FIXED_MODE_TYPES
#undef GIMPLE_FIXED_TYPES_SAT
#undef GIMPLE_FIXED_MODE_TYPES_SAT
#undef TYPE_OK

  return build_nonstandard_integer_type (TYPE_PRECISION (type), unsignedp);
}


/* Return an unsigned type the same as TYPE in other respects.  */

tree
gimple_unsigned_type (tree type)
{
  return gimple_signed_or_unsigned_type (true, type);
}


/* Return a signed type the same as TYPE in other respects.  */

tree
gimple_signed_type (tree type)
{
  return gimple_signed_or_unsigned_type (false, type);
}


/* Return the typed-based alias set for T, which may be an expression
   or a type.  Return -1 if we don't do anything special.  */

alias_set_type
gimple_get_alias_set (tree t)
{
  tree u;

  /* Permit type-punning when accessing a union, provided the access
     is directly through the union.  For example, this code does not
     permit taking the address of a union member and then storing
     through it.  Even the type-punning allowed here is a GCC
     extension, albeit a common and useful one; the C standard says
     that such accesses have implementation-defined behavior.  */
  for (u = t;
       TREE_CODE (u) == COMPONENT_REF || TREE_CODE (u) == ARRAY_REF;
       u = TREE_OPERAND (u, 0))
    if (TREE_CODE (u) == COMPONENT_REF
	&& TREE_CODE (TREE_TYPE (TREE_OPERAND (u, 0))) == UNION_TYPE)
      return 0;

  /* That's all the expressions we handle specially.  */
  if (!TYPE_P (t))
    return -1;

  /* For convenience, follow the C standard when dealing with
     character types.  Any object may be accessed via an lvalue that
     has character type.  */
  if (t == char_type_node
      || t == signed_char_type_node
      || t == unsigned_char_type_node)
    return 0;

  /* Allow aliasing between signed and unsigned variants of the same
     type.  We treat the signed variant as canonical.  */
  if (TREE_CODE (t) == INTEGER_TYPE && TYPE_UNSIGNED (t))
    {
      tree t1 = gimple_signed_type (t);

      /* t1 == t can happen for boolean nodes which are always unsigned.  */
      if (t1 != t)
	return get_alias_set (t1);
    }

  return -1;
}


/* Data structure used to count the number of dereferences to PTR
   inside an expression.  */
struct count_ptr_d
{
  tree ptr;
  unsigned num_stores;
  unsigned num_loads;
};

/* Helper for count_uses_and_derefs.  Called by walk_tree to look for
   (ALIGN/MISALIGNED_)INDIRECT_REF nodes for the pointer passed in DATA.  */

static tree
count_ptr_derefs (tree *tp, int *walk_subtrees, void *data)
{
  struct walk_stmt_info *wi_p = (struct walk_stmt_info *) data;
  struct count_ptr_d *count_p = (struct count_ptr_d *) wi_p->info;

  /* Do not walk inside ADDR_EXPR nodes.  In the expression &ptr->fld,
     pointer 'ptr' is *not* dereferenced, it is simply used to compute
     the address of 'fld' as 'ptr + offsetof(fld)'.  */
  if (TREE_CODE (*tp) == ADDR_EXPR)
    {
      *walk_subtrees = 0;
      return NULL_TREE;
    }

  if (TREE_CODE (*tp) == MEM_REF && TREE_OPERAND (*tp, 0) == count_p->ptr)
    {
      if (wi_p->is_lhs)
	count_p->num_stores++;
      else
	count_p->num_loads++;
    }

  return NULL_TREE;
}

/* Count the number of direct and indirect uses for pointer PTR in
   statement STMT.  The number of direct uses is stored in
   *NUM_USES_P.  Indirect references are counted separately depending
   on whether they are store or load operations.  The counts are
   stored in *NUM_STORES_P and *NUM_LOADS_P.  */

void
count_uses_and_derefs (tree ptr, gimple stmt, unsigned *num_uses_p,
		       unsigned *num_loads_p, unsigned *num_stores_p)
{
  ssa_op_iter i;
  tree use;

  *num_uses_p = 0;
  *num_loads_p = 0;
  *num_stores_p = 0;

  /* Find out the total number of uses of PTR in STMT.  */
  FOR_EACH_SSA_TREE_OPERAND (use, stmt, i, SSA_OP_USE)
    if (use == ptr)
      (*num_uses_p)++;

  /* Now count the number of indirect references to PTR.  This is
     truly awful, but we don't have much choice.  There are no parent
     pointers inside INDIRECT_REFs, so an expression like
     '*x_1 = foo (x_1, *x_1)' needs to be traversed piece by piece to
     find all the indirect and direct uses of x_1 inside.  The only
     shortcut we can take is the fact that GIMPLE only allows
     INDIRECT_REFs inside the expressions below.  */
  if (is_gimple_assign (stmt)
      || gimple_code (stmt) == GIMPLE_RETURN
      || gimple_code (stmt) == GIMPLE_ASM
      || is_gimple_call (stmt))
    {
      struct walk_stmt_info wi;
      struct count_ptr_d count;

      count.ptr = ptr;
      count.num_stores = 0;
      count.num_loads = 0;

      memset (&wi, 0, sizeof (wi));
      wi.info = &count;
      walk_gimple_op (stmt, count_ptr_derefs, &wi);

      *num_stores_p = count.num_stores;
      *num_loads_p = count.num_loads;
    }

  gcc_assert (*num_uses_p >= *num_loads_p + *num_stores_p);
}

/* From a tree operand OP return the base of a load or store operation
   or NULL_TREE if OP is not a load or a store.  */

static tree
get_base_loadstore (tree op)
{
  while (handled_component_p (op))
    op = TREE_OPERAND (op, 0);
  if (DECL_P (op)
      || INDIRECT_REF_P (op)
      || TREE_CODE (op) == MEM_REF
      || TREE_CODE (op) == TARGET_MEM_REF)
    return op;
  return NULL_TREE;
}

/* For the statement STMT call the callbacks VISIT_LOAD, VISIT_STORE and
   VISIT_ADDR if non-NULL on loads, store and address-taken operands
   passing the STMT, the base of the operand and DATA to it.  The base
   will be either a decl, an indirect reference (including TARGET_MEM_REF)
   or the argument of an address expression.
   Returns the results of these callbacks or'ed.  */

bool
walk_stmt_load_store_addr_ops (gimple stmt, void *data,
			       bool (*visit_load)(gimple, tree, void *),
			       bool (*visit_store)(gimple, tree, void *),
			       bool (*visit_addr)(gimple, tree, void *))
{
  bool ret = false;
  unsigned i;
  if (gimple_assign_single_p (stmt))
    {
      tree lhs, rhs;
      if (visit_store)
	{
	  lhs = get_base_loadstore (gimple_assign_lhs (stmt));
	  if (lhs)
	    ret |= visit_store (stmt, lhs, data);
	}
      rhs = gimple_assign_rhs1 (stmt);
      while (handled_component_p (rhs))
	rhs = TREE_OPERAND (rhs, 0);
      if (visit_addr)
	{
	  if (TREE_CODE (rhs) == ADDR_EXPR)
	    ret |= visit_addr (stmt, TREE_OPERAND (rhs, 0), data);
	  else if (TREE_CODE (rhs) == TARGET_MEM_REF
		   && TREE_CODE (TMR_BASE (rhs)) == ADDR_EXPR)
	    ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (rhs), 0), data);
	  else if (TREE_CODE (rhs) == OBJ_TYPE_REF
		   && TREE_CODE (OBJ_TYPE_REF_OBJECT (rhs)) == ADDR_EXPR)
	    ret |= visit_addr (stmt, TREE_OPERAND (OBJ_TYPE_REF_OBJECT (rhs),
						   0), data);
          lhs = gimple_assign_lhs (stmt);
	  if (TREE_CODE (lhs) == TARGET_MEM_REF
              && TREE_CODE (TMR_BASE (lhs)) == ADDR_EXPR)
            ret |= visit_addr (stmt, TREE_OPERAND (TMR_BASE (lhs), 0), data);
	}
      if (visit_load)
	{
	  rhs = get_base_loadstore (rhs);
	  if (rhs)
	    ret |= visit_load (stmt, rhs, data);
	}
    }
  else if (visit_addr
	   && (is_gimple_assign (stmt)
	       || gimple_code (stmt) == GIMPLE_COND))
    {
      for (i = 0; i < gimple_num_ops (stmt); ++i)
	if (gimple_op (stmt, i)
	    && TREE_CODE (gimple_op (stmt, i)) == ADDR_EXPR)
	  ret |= visit_addr (stmt, TREE_OPERAND (gimple_op (stmt, i), 0), data);
    }
  else if (is_gimple_call (stmt))
    {
      if (visit_store)
	{
	  tree lhs = gimple_call_lhs (stmt);
	  if (lhs)
	    {
	      lhs = get_base_loadstore (lhs);
	      if (lhs)
		ret |= visit_store (stmt, lhs, data);
	    }
	}
      if (visit_load || visit_addr)
	for (i = 0; i < gimple_call_num_args (stmt); ++i)
	  {
	    tree rhs = gimple_call_arg (stmt, i);
	    if (visit_addr
		&& TREE_CODE (rhs) == ADDR_EXPR)
	      ret |= visit_addr (stmt, TREE_OPERAND (rhs, 0), data);
	    else if (visit_load)
	      {
		rhs = get_base_loadstore (rhs);
		if (rhs)
		  ret |= visit_load (stmt, rhs, data);
	      }
	  }
      if (visit_addr
	  && gimple_call_chain (stmt)
	  && TREE_CODE (gimple_call_chain (stmt)) == ADDR_EXPR)
	ret |= visit_addr (stmt, TREE_OPERAND (gimple_call_chain (stmt), 0),
			   data);
      if (visit_addr
	  && gimple_call_return_slot_opt_p (stmt)
	  && gimple_call_lhs (stmt) != NULL_TREE
	  && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (stmt))))
	ret |= visit_addr (stmt, gimple_call_lhs (stmt), data);
    }
  else if (gimple_code (stmt) == GIMPLE_ASM)
    {
      unsigned noutputs;
      const char *constraint;
      const char **oconstraints;
      bool allows_mem, allows_reg, is_inout;
      noutputs = gimple_asm_noutputs (stmt);
      oconstraints = XALLOCAVEC (const char *, noutputs);
      if (visit_store || visit_addr)
	for (i = 0; i < gimple_asm_noutputs (stmt); ++i)
	  {
	    tree link = gimple_asm_output_op (stmt, i);
	    tree op = get_base_loadstore (TREE_VALUE (link));
	    if (op && visit_store)
	      ret |= visit_store (stmt, op, data);
	    if (visit_addr)
	      {
		constraint = TREE_STRING_POINTER
		    (TREE_VALUE (TREE_PURPOSE (link)));
		oconstraints[i] = constraint;
		parse_output_constraint (&constraint, i, 0, 0, &allows_mem,
					 &allows_reg, &is_inout);
		if (op && !allows_reg && allows_mem)
		  ret |= visit_addr (stmt, op, data);
	      }
	  }
      if (visit_load || visit_addr)
	for (i = 0; i < gimple_asm_ninputs (stmt); ++i)
	  {
	    tree link = gimple_asm_input_op (stmt, i);
	    tree op = TREE_VALUE (link);
	    if (visit_addr
		&& TREE_CODE (op) == ADDR_EXPR)
	      ret |= visit_addr (stmt, TREE_OPERAND (op, 0), data);
	    else if (visit_load || visit_addr)
	      {
		op = get_base_loadstore (op);
		if (op)
		  {
		    if (visit_load)
		      ret |= visit_load (stmt, op, data);
		    if (visit_addr)
		      {
			constraint = TREE_STRING_POINTER
			    (TREE_VALUE (TREE_PURPOSE (link)));
			parse_input_constraint (&constraint, 0, 0, noutputs,
						0, oconstraints,
						&allows_mem, &allows_reg);
			if (!allows_reg && allows_mem)
			  ret |= visit_addr (stmt, op, data);
		      }
		  }
	      }
	  }
    }
  else if (gimple_code (stmt) == GIMPLE_RETURN)
    {
      tree op = gimple_return_retval (stmt);
      if (op)
	{
	  if (visit_addr
	      && TREE_CODE (op) == ADDR_EXPR)
	    ret |= visit_addr (stmt, TREE_OPERAND (op, 0), data);
	  else if (visit_load)
	    {
	      op = get_base_loadstore (op);
	      if (op)
		ret |= visit_load (stmt, op, data);
	    }
	}
    }
  else if (visit_addr
	   && gimple_code (stmt) == GIMPLE_PHI)
    {
      for (i = 0; i < gimple_phi_num_args (stmt); ++i)
	{
	  tree op = PHI_ARG_DEF (stmt, i);
	  if (TREE_CODE (op) == ADDR_EXPR)
	    ret |= visit_addr (stmt, TREE_OPERAND (op, 0), data);
	}
    }

  return ret;
}

/* Like walk_stmt_load_store_addr_ops but with NULL visit_addr.  IPA-CP
   should make a faster clone for this case.  */

bool
walk_stmt_load_store_ops (gimple stmt, void *data,
			  bool (*visit_load)(gimple, tree, void *),
			  bool (*visit_store)(gimple, tree, void *))
{
  return walk_stmt_load_store_addr_ops (stmt, data,
					visit_load, visit_store, NULL);
}

/* Helper for gimple_ior_addresses_taken_1.  */

static bool
gimple_ior_addresses_taken_1 (gimple stmt ATTRIBUTE_UNUSED,
			      tree addr, void *data)
{
  bitmap addresses_taken = (bitmap)data;
  addr = get_base_address (addr);
  if (addr
      && DECL_P (addr))
    {
      bitmap_set_bit (addresses_taken, DECL_UID (addr));
      return true;
    }
  return false;
}

/* Set the bit for the uid of all decls that have their address taken
   in STMT in the ADDRESSES_TAKEN bitmap.  Returns true if there
   were any in this stmt.  */

bool
gimple_ior_addresses_taken (bitmap addresses_taken, gimple stmt)
{
  return walk_stmt_load_store_addr_ops (stmt, addresses_taken, NULL, NULL,
					gimple_ior_addresses_taken_1);
}


/* Return a printable name for symbol DECL.  */

const char *
gimple_decl_printable_name (tree decl, int verbosity)
{
  if (!DECL_NAME (decl))
    return NULL;

  if (DECL_ASSEMBLER_NAME_SET_P (decl))
    {
      const char *str, *mangled_str;
      int dmgl_opts = DMGL_NO_OPTS;

      if (verbosity >= 2)
	{
	  dmgl_opts = DMGL_VERBOSE
		      | DMGL_ANSI
		      | DMGL_GNU_V3
		      | DMGL_RET_POSTFIX;
	  if (TREE_CODE (decl) == FUNCTION_DECL)
	    dmgl_opts |= DMGL_PARAMS;
	}

      mangled_str = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
      str = cplus_demangle_v3 (mangled_str, dmgl_opts);
      return (str) ? str : mangled_str;
    }

  return IDENTIFIER_POINTER (DECL_NAME (decl));
}

/* Return true when STMT is builtins call to CODE.  */

bool
gimple_call_builtin_p (gimple stmt, enum built_in_function code)
{
  tree fndecl;
  return (is_gimple_call (stmt)
	  && (fndecl = gimple_call_fndecl (stmt)) != NULL
	  && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
	  && DECL_FUNCTION_CODE (fndecl) == code);
}

#include "gt-gimple.h"