aboutsummaryrefslogtreecommitdiff
path: root/gcc/cgraphunit.c
blob: e6a0ea65b2634b6954a0ba301b5815370c365072 (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
/* Callgraph based interprocedural optimizations.
   Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
   2011 Free Software Foundation, Inc.
   Contributed by Jan Hubicka

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/>.  */

/* This module implements main driver of compilation process as well as
   few basic interprocedural optimizers.

   The main scope of this file is to act as an interface in between
   tree based frontends and the backend (and middle end)

   The front-end is supposed to use following functionality:

    - cgraph_finalize_function

      This function is called once front-end has parsed whole body of function
      and it is certain that the function body nor the declaration will change.

      (There is one exception needed for implementing GCC extern inline
	function.)

    - varpool_finalize_variable

      This function has same behavior as the above but is used for static
      variables.

    - cgraph_finalize_compilation_unit

      This function is called once (source level) compilation unit is finalized
      and it will no longer change.

      In the the call-graph construction and local function
      analysis takes place here.  Bodies of unreachable functions are released
      to conserve memory usage.

      The function can be called multiple times when multiple source level
      compilation units are combined (such as in C frontend)

    - cgraph_optimize

      In this unit-at-a-time compilation the intra procedural analysis takes
      place here.  In particular the static functions whose address is never
      taken are marked as local.  Backend can then use this information to
      modify calling conventions, do better inlining or similar optimizations.

    - cgraph_mark_needed_node
    - varpool_mark_needed_node

      When function or variable is referenced by some hidden way the call-graph
      data structure must be updated accordingly by this function.
      There should be little need to call this function and all the references
      should be made explicit to cgraph code.  At present these functions are
      used by C++ frontend to explicitly mark the keyed methods.

    - analyze_expr callback

      This function is responsible for lowering tree nodes not understood by
      generic code into understandable ones or alternatively marking
      callgraph and varpool nodes referenced by the as needed.

      ??? On the tree-ssa genericizing should take place here and we will avoid
      need for these hooks (replacing them by genericizing hook)

        Analyzing of all functions is deferred
	to cgraph_finalize_compilation_unit and expansion into cgraph_optimize.

	In cgraph_finalize_compilation_unit the reachable functions are
	analyzed.  During analysis the call-graph edges from reachable
	functions are constructed and their destinations are marked as
	reachable.  References to functions and variables are discovered too
	and variables found to be needed output to the assembly file.  Via
	mark_referenced call in assemble_variable functions referenced by
	static variables are noticed too.

	The intra-procedural information is produced and its existence
	indicated by global_info_ready.  Once this flag is set it is impossible
	to change function from !reachable to reachable and thus
	assemble_variable no longer call mark_referenced.

	Finally the call-graph is topologically sorted and all reachable functions
	that has not been completely inlined or are not external are output.

	??? It is possible that reference to function or variable is optimized
	out.  We can not deal with this nicely because topological order is not
	suitable for it.  For tree-ssa we may consider another pass doing
	optimization and re-discovering reachable functions.

	??? Reorganize code so variables are output very last and only if they
	really has been referenced by produced code, so we catch more cases
	where reference has been optimized out.  */


#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
#include "rtl.h"
#include "tree-flow.h"
#include "tree-inline.h"
#include "langhooks.h"
#include "pointer-set.h"
#include "toplev.h"
#include "flags.h"
#include "ggc.h"
#include "debug.h"
#include "target.h"
#include "cgraph.h"
#include "diagnostic.h"
#include "tree-pretty-print.h"
#include "gimple-pretty-print.h"
#include "timevar.h"
#include "params.h"
#include "fibheap.h"
#include "intl.h"
#include "function.h"
#include "ipa-prop.h"
#include "gimple.h"
#include "tree-iterator.h"
#include "tree-pass.h"
#include "tree-dump.h"
#include "output.h"
#include "coverage.h"
#include "plugin.h"

static void cgraph_expand_all_functions (void);
static void cgraph_mark_functions_to_output (void);
static void cgraph_expand_function (struct cgraph_node *);
static void cgraph_output_pending_asms (void);
static void cgraph_analyze_function (struct cgraph_node *);

FILE *cgraph_dump_file;

/* Used for vtable lookup in thunk adjusting.  */
static GTY (()) tree vtable_entry_type;

/* Determine if function DECL is needed.  That is, visible to something
   either outside this translation unit, something magic in the system
   configury.  */

bool
cgraph_decide_is_function_needed (struct cgraph_node *node, tree decl)
{
  /* If the user told us it is used, then it must be so.  */
  if (node->local.externally_visible)
    return true;

  /* ??? If the assembler name is set by hand, it is possible to assemble
     the name later after finalizing the function and the fact is noticed
     in assemble_name then.  This is arguably a bug.  */
  if (DECL_ASSEMBLER_NAME_SET_P (decl)
      && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
    return true;

  /* With -fkeep-inline-functions we are keeping all inline functions except
     for extern inline ones.  */
  if (flag_keep_inline_functions
      && DECL_DECLARED_INLINE_P (decl)
      && !DECL_EXTERNAL (decl)
      && !lookup_attribute ("always_inline", DECL_ATTRIBUTES (decl)))
     return true;

  /* If we decided it was needed before, but at the time we didn't have
     the body of the function available, then it's still needed.  We have
     to go back and re-check its dependencies now.  */
  if (node->needed)
    return true;

  /* Externally visible functions must be output.  The exception is
     COMDAT functions that must be output only when they are needed.

     When not optimizing, also output the static functions. (see
     PR24561), but don't do so for always_inline functions, functions
     declared inline and nested functions.  These were optimized out
     in the original implementation and it is unclear whether we want
     to change the behavior here.  */
  if (((TREE_PUBLIC (decl)
	|| (!optimize
	    && !node->local.disregard_inline_limits
	    && !DECL_DECLARED_INLINE_P (decl)
	    && !(DECL_CONTEXT (decl)
		 && TREE_CODE (DECL_CONTEXT (decl)) == FUNCTION_DECL)))
       && !flag_whole_program
       && !flag_lto)
      && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
    return true;

  return false;
}

/* Process CGRAPH_NEW_FUNCTIONS and perform actions necessary to add these
   functions into callgraph in a way so they look like ordinary reachable
   functions inserted into callgraph already at construction time.  */

bool
cgraph_process_new_functions (void)
{
  bool output = false;
  tree fndecl;
  struct cgraph_node *node;

  varpool_analyze_pending_decls ();
  /*  Note that this queue may grow as its being processed, as the new
      functions may generate new ones.  */
  while (cgraph_new_nodes)
    {
      node = cgraph_new_nodes;
      fndecl = node->decl;
      cgraph_new_nodes = cgraph_new_nodes->next_needed;
      switch (cgraph_state)
	{
	case CGRAPH_STATE_CONSTRUCTION:
	  /* At construction time we just need to finalize function and move
	     it into reachable functions list.  */

	  node->next_needed = NULL;
	  cgraph_finalize_function (fndecl, false);
	  cgraph_mark_reachable_node (node);
	  output = true;
	  break;

	case CGRAPH_STATE_IPA:
	case CGRAPH_STATE_IPA_SSA:
	  /* When IPA optimization already started, do all essential
	     transformations that has been already performed on the whole
	     cgraph but not on this function.  */

	  gimple_register_cfg_hooks ();
	  if (!node->analyzed)
	    cgraph_analyze_function (node);
	  push_cfun (DECL_STRUCT_FUNCTION (fndecl));
	  current_function_decl = fndecl;
	  if ((cgraph_state == CGRAPH_STATE_IPA_SSA
	      && !gimple_in_ssa_p (DECL_STRUCT_FUNCTION (fndecl)))
	      /* When not optimizing, be sure we run early local passes anyway
		 to expand OMP.  */
	      || !optimize)
	    execute_pass_list (pass_early_local_passes.pass.sub);
	  else
	    compute_inline_parameters (node);
	  free_dominance_info (CDI_POST_DOMINATORS);
	  free_dominance_info (CDI_DOMINATORS);
	  pop_cfun ();
	  current_function_decl = NULL;
	  break;

	case CGRAPH_STATE_EXPANSION:
	  /* Functions created during expansion shall be compiled
	     directly.  */
	  node->process = 0;
	  cgraph_expand_function (node);
	  break;

	default:
	  gcc_unreachable ();
	  break;
	}
      cgraph_call_function_insertion_hooks (node);
      varpool_analyze_pending_decls ();
    }
  return output;
}

/* As an GCC extension we allow redefinition of the function.  The
   semantics when both copies of bodies differ is not well defined.
   We replace the old body with new body so in unit at a time mode
   we always use new body, while in normal mode we may end up with
   old body inlined into some functions and new body expanded and
   inlined in others.

   ??? It may make more sense to use one body for inlining and other
   body for expanding the function but this is difficult to do.  */

static void
cgraph_reset_node (struct cgraph_node *node)
{
  /* If node->process is set, then we have already begun whole-unit analysis.
     This is *not* testing for whether we've already emitted the function.
     That case can be sort-of legitimately seen with real function redefinition
     errors.  I would argue that the front end should never present us with
     such a case, but don't enforce that for now.  */
  gcc_assert (!node->process);

  /* Reset our data structures so we can analyze the function again.  */
  memset (&node->local, 0, sizeof (node->local));
  memset (&node->global, 0, sizeof (node->global));
  memset (&node->rtl, 0, sizeof (node->rtl));
  node->analyzed = false;
  node->local.redefined_extern_inline = true;
  node->local.finalized = false;

  cgraph_node_remove_callees (node);

  /* We may need to re-queue the node for assembling in case
     we already proceeded it and ignored as not needed or got
     a re-declaration in IMA mode.  */
  if (node->reachable)
    {
      struct cgraph_node *n;

      for (n = cgraph_nodes_queue; n; n = n->next_needed)
	if (n == node)
	  break;
      if (!n)
	node->reachable = 0;
    }
}

static void
cgraph_lower_function (struct cgraph_node *node)
{
  if (node->lowered)
    return;

  if (node->nested)
    lower_nested_functions (node->decl);
  gcc_assert (!node->nested);

  tree_lowering_passes (node->decl);
  node->lowered = true;
}

/* DECL has been parsed.  Take it, queue it, compile it at the whim of the
   logic in effect.  If NESTED is true, then our caller cannot stand to have
   the garbage collector run at the moment.  We would need to either create
   a new GC context, or just not compile right now.  */

void
cgraph_finalize_function (tree decl, bool nested)
{
  struct cgraph_node *node = cgraph_node (decl);

  if (node->local.finalized)
    cgraph_reset_node (node);

  node->pid = cgraph_max_pid ++;
  notice_global_symbol (decl);
  node->local.finalized = true;
  node->lowered = DECL_STRUCT_FUNCTION (decl)->cfg != NULL;
  node->finalized_by_frontend = true;

  if (cgraph_decide_is_function_needed (node, decl))
    cgraph_mark_needed_node (node);

  /* Since we reclaim unreachable nodes at the end of every language
     level unit, we need to be conservative about possible entry points
     there.  */
  if ((TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
      || DECL_STATIC_CONSTRUCTOR (decl)
      || DECL_STATIC_DESTRUCTOR (decl)
      /* COMDAT virtual functions may be referenced by vtable from
	 other compilation unit.  Still we want to devirtualize calls
	 to those so we need to analyze them.
	 FIXME: We should introduce may edges for this purpose and update
	 their handling in unreachable function removal and inliner too.  */
      || (DECL_VIRTUAL_P (decl) && (DECL_COMDAT (decl) || DECL_EXTERNAL (decl))))
    cgraph_mark_reachable_node (node);

  /* If we've not yet emitted decl, tell the debug info about it.  */
  if (!TREE_ASM_WRITTEN (decl))
    (*debug_hooks->deferred_inline_function) (decl);

  /* Possibly warn about unused parameters.  */
  if (warn_unused_parameter)
    do_warn_unused_parameter (decl);

  if (!nested)
    ggc_collect ();
}

/* C99 extern inline keywords allow changing of declaration after function
   has been finalized.  We need to re-decide if we want to mark the function as
   needed then.   */

void
cgraph_mark_if_needed (tree decl)
{
  struct cgraph_node *node = cgraph_node (decl);
  if (node->local.finalized && cgraph_decide_is_function_needed (node, decl))
    cgraph_mark_needed_node (node);
}

/* Return TRUE if NODE2 is equivalent to NODE or its clone.  */
static bool
clone_of_p (struct cgraph_node *node, struct cgraph_node *node2)
{
  while (node != node2 && node2)
    node2 = node2->clone_of;
  return node2 != NULL;
}

/* Verify edge E count and frequency.  */

static bool
verify_edge_count_and_frequency (struct cgraph_edge *e)
{
  bool error_found = false;
  if (e->count < 0)
    {
      error ("caller edge count is negative");
      error_found = true;
    }
  if (e->frequency < 0)
    {
      error ("caller edge frequency is negative");
      error_found = true;
    }
  if (e->frequency > CGRAPH_FREQ_MAX)
    {
      error ("caller edge frequency is too large");
      error_found = true;
    }
  if (gimple_has_body_p (e->caller->decl)
      && !e->caller->global.inlined_to
      && (e->frequency
	  != compute_call_stmt_bb_frequency (e->caller->decl,
					     gimple_bb (e->call_stmt))))
    {
      error ("caller edge frequency %i does not match BB frequency %i",
	     e->frequency,
	     compute_call_stmt_bb_frequency (e->caller->decl,
					     gimple_bb (e->call_stmt)));
      error_found = true;
    }
  return error_found;
}

/* Switch to THIS_CFUN if needed and print STMT to stderr.  */
static void
cgraph_debug_gimple_stmt (struct function *this_cfun, gimple stmt)
{
  /* debug_gimple_stmt needs correct cfun */
  if (cfun != this_cfun)
    set_cfun (this_cfun);
  debug_gimple_stmt (stmt);
}

/* Verify cgraph nodes of given cgraph node.  */
DEBUG_FUNCTION void
verify_cgraph_node (struct cgraph_node *node)
{
  struct cgraph_edge *e;
  struct function *this_cfun = DECL_STRUCT_FUNCTION (node->decl);
  basic_block this_block;
  gimple_stmt_iterator gsi;
  bool error_found = false;

  if (seen_error ())
    return;

  timevar_push (TV_CGRAPH_VERIFY);
  for (e = node->callees; e; e = e->next_callee)
    if (e->aux)
      {
	error ("aux field set for edge %s->%s",
	       identifier_to_locale (cgraph_node_name (e->caller)),
	       identifier_to_locale (cgraph_node_name (e->callee)));
	error_found = true;
      }
  if (node->count < 0)
    {
      error ("execution count is negative");
      error_found = true;
    }
  if (node->global.inlined_to && node->local.externally_visible)
    {
      error ("externally visible inline clone");
      error_found = true;
    }
  if (node->global.inlined_to && node->address_taken)
    {
      error ("inline clone with address taken");
      error_found = true;
    }
  if (node->global.inlined_to && node->needed)
    {
      error ("inline clone is needed");
      error_found = true;
    }
  for (e = node->indirect_calls; e; e = e->next_callee)
    {
      if (e->aux)
	{
	  error ("aux field set for indirect edge from %s",
		 identifier_to_locale (cgraph_node_name (e->caller)));
	  error_found = true;
	}
      if (!e->indirect_unknown_callee
	  || !e->indirect_info)
	{
	  error ("An indirect edge from %s is not marked as indirect or has "
		 "associated indirect_info, the corresponding statement is: ",
		 identifier_to_locale (cgraph_node_name (e->caller)));
	  cgraph_debug_gimple_stmt (this_cfun, e->call_stmt);
	  error_found = true;
	}
    }
  for (e = node->callers; e; e = e->next_caller)
    {
      if (verify_edge_count_and_frequency (e))
	error_found = true;
      if (!e->inline_failed)
	{
	  if (node->global.inlined_to
	      != (e->caller->global.inlined_to
		  ? e->caller->global.inlined_to : e->caller))
	    {
	      error ("inlined_to pointer is wrong");
	      error_found = true;
	    }
	  if (node->callers->next_caller)
	    {
	      error ("multiple inline callers");
	      error_found = true;
	    }
	}
      else
	if (node->global.inlined_to)
	  {
	    error ("inlined_to pointer set for noninline callers");
	    error_found = true;
	  }
    }
  for (e = node->indirect_calls; e; e = e->next_callee)
    if (verify_edge_count_and_frequency (e))
      error_found = true;
  if (!node->callers && node->global.inlined_to)
    {
      error ("inlined_to pointer is set but no predecessors found");
      error_found = true;
    }
  if (node->global.inlined_to == node)
    {
      error ("inlined_to pointer refers to itself");
      error_found = true;
    }

  if (!cgraph_get_node (node->decl))
    {
      error ("node not found in cgraph_hash");
      error_found = true;
    }

  if (node->clone_of)
    {
      struct cgraph_node *n;
      for (n = node->clone_of->clones; n; n = n->next_sibling_clone)
        if (n == node)
	  break;
      if (!n)
	{
	  error ("node has wrong clone_of");
	  error_found = true;
	}
    }
  if (node->clones)
    {
      struct cgraph_node *n;
      for (n = node->clones; n; n = n->next_sibling_clone)
        if (n->clone_of != node)
	  break;
      if (n)
	{
	  error ("node has wrong clone list");
	  error_found = true;
	}
    }
  if ((node->prev_sibling_clone || node->next_sibling_clone) && !node->clone_of)
    {
       error ("node is in clone list but it is not clone");
       error_found = true;
    }
  if (!node->prev_sibling_clone && node->clone_of && node->clone_of->clones != node)
    {
      error ("node has wrong prev_clone pointer");
      error_found = true;
    }
  if (node->prev_sibling_clone && node->prev_sibling_clone->next_sibling_clone != node)
    {
      error ("double linked list of clones corrupted");
      error_found = true;
    }
  if (node->same_comdat_group)
    {
      struct cgraph_node *n = node->same_comdat_group;

      if (!DECL_ONE_ONLY (node->decl))
	{
	  error ("non-DECL_ONE_ONLY node in a same_comdat_group list");
	  error_found = true;
	}
      if (n == node)
	{
	  error ("node is alone in a comdat group");
	  error_found = true;
	}
      do
	{
	  if (!n->same_comdat_group)
	    {
	      error ("same_comdat_group is not a circular list");
	      error_found = true;
	      break;
	    }
	  n = n->same_comdat_group;
	}
      while (n != node);
    }

  if (node->analyzed && gimple_has_body_p (node->decl)
      && !TREE_ASM_WRITTEN (node->decl)
      && (!DECL_EXTERNAL (node->decl) || node->global.inlined_to)
      && !flag_wpa)
    {
      if (this_cfun->cfg)
	{
	  /* The nodes we're interested in are never shared, so walk
	     the tree ignoring duplicates.  */
	  struct pointer_set_t *visited_nodes = pointer_set_create ();
	  /* Reach the trees by walking over the CFG, and note the
	     enclosing basic-blocks in the call edges.  */
	  FOR_EACH_BB_FN (this_block, this_cfun)
	    for (gsi = gsi_start_bb (this_block);
                 !gsi_end_p (gsi);
                 gsi_next (&gsi))
	      {
		gimple stmt = gsi_stmt (gsi);
		if (is_gimple_call (stmt))
		  {
		    struct cgraph_edge *e = cgraph_edge (node, stmt);
		    tree decl = gimple_call_fndecl (stmt);
		    if (e)
		      {
			if (e->aux)
			  {
			    error ("shared call_stmt:");
			    cgraph_debug_gimple_stmt (this_cfun, stmt);
			    error_found = true;
			  }
			if (!e->indirect_unknown_callee)
			  {
			    struct cgraph_node *n;

			    if (e->callee->same_body_alias)
			      {
				error ("edge points to same body alias:");
				debug_tree (e->callee->decl);
				error_found = true;
			      }
			    else if (!e->callee->global.inlined_to
				     && decl
				     && cgraph_get_node (decl)
				     && (e->callee->former_clone_of
					 != cgraph_get_node (decl)->decl)
				     && !clone_of_p (cgraph_node (decl),
						     e->callee))
			      {
				error ("edge points to wrong declaration:");
				debug_tree (e->callee->decl);
				fprintf (stderr," Instead of:");
				debug_tree (decl);
				error_found = true;
			      }
			    else if (decl
				     && (n = cgraph_get_node_or_alias (decl))
				     && (n->same_body_alias
					 && n->thunk.thunk_p))
			      {
				error ("a call to thunk improperly represented "
				       "in the call graph:");
				cgraph_debug_gimple_stmt (this_cfun, stmt);
				error_found = true;
			      }
			  }
			else if (decl)
			  {
			    error ("an indirect edge with unknown callee "
				   "corresponding to a call_stmt with "
				   "a known declaration:");
			    error_found = true;
			    cgraph_debug_gimple_stmt (this_cfun, e->call_stmt);
			  }
			e->aux = (void *)1;
		      }
		    else if (decl)
		      {
			error ("missing callgraph edge for call stmt:");
			cgraph_debug_gimple_stmt (this_cfun, stmt);
			error_found = true;
		      }
		  }
	      }
	  pointer_set_destroy (visited_nodes);
	}
      else
	/* No CFG available?!  */
	gcc_unreachable ();

      for (e = node->callees; e; e = e->next_callee)
	{
	  if (!e->aux)
	    {
	      error ("edge %s->%s has no corresponding call_stmt",
		     identifier_to_locale (cgraph_node_name (e->caller)),
		     identifier_to_locale (cgraph_node_name (e->callee)));
	      cgraph_debug_gimple_stmt (this_cfun, e->call_stmt);
	      error_found = true;
	    }
	  e->aux = 0;
	}
      for (e = node->indirect_calls; e; e = e->next_callee)
	{
	  if (!e->aux)
	    {
	      error ("an indirect edge from %s has no corresponding call_stmt",
		     identifier_to_locale (cgraph_node_name (e->caller)));
	      cgraph_debug_gimple_stmt (this_cfun, e->call_stmt);
	      error_found = true;
	    }
	  e->aux = 0;
	}
    }
  if (error_found)
    {
      dump_cgraph_node (stderr, node);
      internal_error ("verify_cgraph_node failed");
    }
  timevar_pop (TV_CGRAPH_VERIFY);
}

/* Verify whole cgraph structure.  */
DEBUG_FUNCTION void
verify_cgraph (void)
{
  struct cgraph_node *node;

  if (seen_error ())
    return;

  for (node = cgraph_nodes; node; node = node->next)
    verify_cgraph_node (node);
}

/* Output all asm statements we have stored up to be output.  */

static void
cgraph_output_pending_asms (void)
{
  struct cgraph_asm_node *can;

  if (seen_error ())
    return;

  for (can = cgraph_asm_nodes; can; can = can->next)
    assemble_asm (can->asm_str);
  cgraph_asm_nodes = NULL;
}

/* Analyze the function scheduled to be output.  */
static void
cgraph_analyze_function (struct cgraph_node *node)
{
  tree save = current_function_decl;
  tree decl = node->decl;

  current_function_decl = decl;
  push_cfun (DECL_STRUCT_FUNCTION (decl));

  assign_assembler_name_if_neeeded (node->decl);

  /* disregard_inline_limits affects topological order of the early optimization,
     so we need to compute it ahead of rest of inline parameters.  */
  node->local.disregard_inline_limits
    = DECL_DISREGARD_INLINE_LIMITS (node->decl);

  /* Make sure to gimplify bodies only once.  During analyzing a
     function we lower it, which will require gimplified nested
     functions, so we can end up here with an already gimplified
     body.  */
  if (!gimple_body (decl))
    gimplify_function_tree (decl);
  dump_function (TDI_generic, decl);

  cgraph_lower_function (node);
  node->analyzed = true;

  pop_cfun ();
  current_function_decl = save;
}

/* Process attributes common for vars and functions.  */

static void
process_common_attributes (tree decl)
{
  tree weakref = lookup_attribute ("weakref", DECL_ATTRIBUTES (decl));

  if (weakref && !lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
    {
      warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wattributes,
		  "%<weakref%> attribute should be accompanied with"
		  " an %<alias%> attribute");
      DECL_WEAK (decl) = 0;
      DECL_ATTRIBUTES (decl) = remove_attribute ("weakref",
						 DECL_ATTRIBUTES (decl));
    }
}

/* Look for externally_visible and used attributes and mark cgraph nodes
   accordingly.

   We cannot mark the nodes at the point the attributes are processed (in
   handle_*_attribute) because the copy of the declarations available at that
   point may not be canonical.  For example, in:

    void f();
    void f() __attribute__((used));

   the declaration we see in handle_used_attribute will be the second
   declaration -- but the front end will subsequently merge that declaration
   with the original declaration and discard the second declaration.

   Furthermore, we can't mark these nodes in cgraph_finalize_function because:

    void f() {}
    void f() __attribute__((externally_visible));

   is valid.

   So, we walk the nodes at the end of the translation unit, applying the
   attributes at that point.  */

static void
process_function_and_variable_attributes (struct cgraph_node *first,
                                          struct varpool_node *first_var)
{
  struct cgraph_node *node;
  struct varpool_node *vnode;

  for (node = cgraph_nodes; node != first; node = node->next)
    {
      tree decl = node->decl;
      if (DECL_PRESERVE_P (decl))
	cgraph_mark_needed_node (node);
      if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
	  && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl))
	  && TREE_PUBLIC (node->decl))
	{
	  if (node->local.finalized)
	    cgraph_mark_needed_node (node);
	}
      else if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl)))
	{
	  if (! TREE_PUBLIC (node->decl))
	    warning_at (DECL_SOURCE_LOCATION (node->decl), OPT_Wattributes,
			"%<externally_visible%>"
			" attribute have effect only on public objects");
	  else if (node->local.finalized)
	     cgraph_mark_needed_node (node);
	}
      if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl))
	  && node->local.finalized)
	{
	  warning_at (DECL_SOURCE_LOCATION (node->decl), OPT_Wattributes,
		      "%<weakref%> attribute ignored"
		      " because function is defined");
	  DECL_WEAK (decl) = 0;
	  DECL_ATTRIBUTES (decl) = remove_attribute ("weakref",
						     DECL_ATTRIBUTES (decl));
	}
      process_common_attributes (decl);
    }
  for (vnode = varpool_nodes; vnode != first_var; vnode = vnode->next)
    {
      tree decl = vnode->decl;
      if (DECL_PRESERVE_P (decl))
	{
	  vnode->force_output = true;
	  if (vnode->finalized)
	    varpool_mark_needed_node (vnode);
	}
      if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
	  && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl))
	  && TREE_PUBLIC (vnode->decl))
	{
	  if (vnode->finalized)
	    varpool_mark_needed_node (vnode);
	}
      else if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl)))
	{
	  if (! TREE_PUBLIC (vnode->decl))
	    warning_at (DECL_SOURCE_LOCATION (vnode->decl), OPT_Wattributes,
			"%<externally_visible%>"
			" attribute have effect only on public objects");
	  else if (vnode->finalized)
	    varpool_mark_needed_node (vnode);
	}
      if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl))
	  && vnode->finalized
	  && DECL_INITIAL (decl))
	{
	  warning_at (DECL_SOURCE_LOCATION (vnode->decl), OPT_Wattributes,
		      "%<weakref%> attribute ignored"
		      " because variable is initialized");
	  DECL_WEAK (decl) = 0;
	  DECL_ATTRIBUTES (decl) = remove_attribute ("weakref",
						      DECL_ATTRIBUTES (decl));
	}
      process_common_attributes (decl);
    }
}

/* Process CGRAPH_NODES_NEEDED queue, analyze each function (and transitively
   each reachable functions) and build cgraph.
   The function can be called multiple times after inserting new nodes
   into beginning of queue.  Just the new part of queue is re-scanned then.  */

static void
cgraph_analyze_functions (void)
{
  /* Keep track of already processed nodes when called multiple times for
     intermodule optimization.  */
  static struct cgraph_node *first_analyzed;
  struct cgraph_node *first_processed = first_analyzed;
  static struct varpool_node *first_analyzed_var;
  struct cgraph_node *node, *next;

  bitmap_obstack_initialize (NULL);
  process_function_and_variable_attributes (first_processed,
					    first_analyzed_var);
  first_processed = cgraph_nodes;
  first_analyzed_var = varpool_nodes;
  varpool_analyze_pending_decls ();
  if (cgraph_dump_file)
    {
      fprintf (cgraph_dump_file, "Initial entry points:");
      for (node = cgraph_nodes; node != first_analyzed; node = node->next)
	if (node->needed)
	  fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
      fprintf (cgraph_dump_file, "\n");
    }
  cgraph_process_new_functions ();

  /* Propagate reachability flag and lower representation of all reachable
     functions.  In the future, lowering will introduce new functions and
     new entry points on the way (by template instantiation and virtual
     method table generation for instance).  */
  while (cgraph_nodes_queue)
    {
      struct cgraph_edge *edge;
      tree decl = cgraph_nodes_queue->decl;

      node = cgraph_nodes_queue;
      cgraph_nodes_queue = cgraph_nodes_queue->next_needed;
      node->next_needed = NULL;

      /* ??? It is possible to create extern inline function and later using
	 weak alias attribute to kill its body. See
	 gcc.c-torture/compile/20011119-1.c  */
      if (!DECL_STRUCT_FUNCTION (decl))
	{
	  cgraph_reset_node (node);
	  continue;
	}

      if (!node->analyzed)
	cgraph_analyze_function (node);

      for (edge = node->callees; edge; edge = edge->next_callee)
	if (!edge->callee->reachable)
	  cgraph_mark_reachable_node (edge->callee);

      if (node->same_comdat_group)
	{
	  for (next = node->same_comdat_group;
	       next != node;
	       next = next->same_comdat_group)
	    cgraph_mark_reachable_node (next);
	}

      /* If decl is a clone of an abstract function, mark that abstract
	 function so that we don't release its body. The DECL_INITIAL() of that
         abstract function declaration will be later needed to output debug info.  */
      if (DECL_ABSTRACT_ORIGIN (decl))
	{
	  struct cgraph_node *origin_node = cgraph_node (DECL_ABSTRACT_ORIGIN (decl));
	  origin_node->abstract_and_needed = true;
	}

      /* We finalize local static variables during constructing callgraph
         edges.  Process their attributes too.  */
      process_function_and_variable_attributes (first_processed,
						first_analyzed_var);
      first_processed = cgraph_nodes;
      first_analyzed_var = varpool_nodes;
      varpool_analyze_pending_decls ();
      cgraph_process_new_functions ();
    }

  /* Collect entry points to the unit.  */
  if (cgraph_dump_file)
    {
      fprintf (cgraph_dump_file, "Unit entry points:");
      for (node = cgraph_nodes; node != first_analyzed; node = node->next)
	if (node->needed)
	  fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
      fprintf (cgraph_dump_file, "\n\nInitial ");
      dump_cgraph (cgraph_dump_file);
      dump_varpool (cgraph_dump_file);
    }

  if (cgraph_dump_file)
    fprintf (cgraph_dump_file, "\nReclaiming functions:");

  for (node = cgraph_nodes; node != first_analyzed; node = next)
    {
      tree decl = node->decl;
      next = node->next;

      if (node->local.finalized && !gimple_has_body_p (decl))
	cgraph_reset_node (node);

      if (!node->reachable && gimple_has_body_p (decl))
	{
	  if (cgraph_dump_file)
	    fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
	  cgraph_remove_node (node);
	  continue;
	}
      else
	node->next_needed = NULL;
      gcc_assert (!node->local.finalized || gimple_has_body_p (decl));
      gcc_assert (node->analyzed == node->local.finalized);
    }
  if (cgraph_dump_file)
    {
      fprintf (cgraph_dump_file, "\n\nReclaimed ");
      dump_cgraph (cgraph_dump_file);
      dump_varpool (cgraph_dump_file);
    }
  bitmap_obstack_release (NULL);
  first_analyzed = cgraph_nodes;
  ggc_collect ();
}


/* Analyze the whole compilation unit once it is parsed completely.  */

void
cgraph_finalize_compilation_unit (void)
{
  timevar_push (TV_CGRAPH);

  /* Do not skip analyzing the functions if there were errors, we
     miss diagnostics for following functions otherwise.  */

  /* Emit size functions we didn't inline.  */
  finalize_size_functions ();

  /* Mark alias targets necessary and emit diagnostics.  */
  finish_aliases_1 ();

  if (!quiet_flag)
    {
      fprintf (stderr, "\nAnalyzing compilation unit\n");
      fflush (stderr);
    }

  /* Gimplify and lower all functions, compute reachability and
     remove unreachable nodes.  */
  cgraph_analyze_functions ();

  /* Mark alias targets necessary and emit diagnostics.  */
  finish_aliases_1 ();

  /* Gimplify and lower thunks.  */
  cgraph_analyze_functions ();

  /* Finally drive the pass manager.  */
  cgraph_optimize ();

  timevar_pop (TV_CGRAPH);
}


/* Figure out what functions we want to assemble.  */

static void
cgraph_mark_functions_to_output (void)
{
  struct cgraph_node *node;
#ifdef ENABLE_CHECKING
  bool check_same_comdat_groups = false;

  for (node = cgraph_nodes; node; node = node->next)
    gcc_assert (!node->process);
#endif

  for (node = cgraph_nodes; node; node = node->next)
    {
      tree decl = node->decl;
      struct cgraph_edge *e;

      gcc_assert (!node->process || node->same_comdat_group);
      if (node->process)
	continue;

      for (e = node->callers; e; e = e->next_caller)
	if (e->inline_failed)
	  break;

      /* We need to output all local functions that are used and not
	 always inlined, as well as those that are reachable from
	 outside the current compilation unit.  */
      if (node->analyzed
	  && !node->global.inlined_to
	  && (!cgraph_only_called_directly_p (node)
	      || (e && node->reachable))
	  && !TREE_ASM_WRITTEN (decl)
	  && !DECL_EXTERNAL (decl))
	{
	  node->process = 1;
	  if (node->same_comdat_group)
	    {
	      struct cgraph_node *next;
	      for (next = node->same_comdat_group;
		   next != node;
		   next = next->same_comdat_group)
		next->process = 1;
	    }
	}
      else if (node->same_comdat_group)
	{
#ifdef ENABLE_CHECKING
	  check_same_comdat_groups = true;
#endif
	}
      else
	{
	  /* We should've reclaimed all functions that are not needed.  */
#ifdef ENABLE_CHECKING
	  if (!node->global.inlined_to
	      && gimple_has_body_p (decl)
	      /* FIXME: in ltrans unit when offline copy is outside partition but inline copies
		 are inside partition, we can end up not removing the body since we no longer
		 have analyzed node pointing to it.  */
	      && !node->in_other_partition
	      && !DECL_EXTERNAL (decl))
	    {
	      dump_cgraph_node (stderr, node);
	      internal_error ("failed to reclaim unneeded function");
	    }
#endif
	  gcc_assert (node->global.inlined_to
		      || !gimple_has_body_p (decl)
		      || node->in_other_partition
		      || DECL_EXTERNAL (decl));

	}

    }
#ifdef ENABLE_CHECKING
  if (check_same_comdat_groups)
    for (node = cgraph_nodes; node; node = node->next)
      if (node->same_comdat_group && !node->process)
	{
	  tree decl = node->decl;
	  if (!node->global.inlined_to
	      && gimple_has_body_p (decl)
	      /* FIXME: in ltrans unit when offline copy is outside partition but inline copies
		 are inside partition, we can end up not removing the body since we no longer
		 have analyzed node pointing to it.  */
	      && !node->in_other_partition
	      && !DECL_EXTERNAL (decl))
	    {
	      dump_cgraph_node (stderr, node);
	      internal_error ("failed to reclaim unneeded function");
	    }
	}
#endif
}

/* DECL is FUNCTION_DECL.  Initialize datastructures so DECL is a function
   in lowered gimple form.
   
   Set current_function_decl and cfun to newly constructed empty function body.
   return basic block in the function body.  */

static basic_block
init_lowered_empty_function (tree decl)
{
  basic_block bb;

  current_function_decl = decl;
  allocate_struct_function (decl, false);
  gimple_register_cfg_hooks ();
  init_empty_tree_cfg ();
  init_tree_ssa (cfun);
  init_ssa_operands ();
  cfun->gimple_df->in_ssa_p = true;
  DECL_INITIAL (decl) = make_node (BLOCK);

  DECL_SAVED_TREE (decl) = error_mark_node;
  cfun->curr_properties |=
    (PROP_gimple_lcf | PROP_gimple_leh | PROP_cfg | PROP_referenced_vars |
     PROP_ssa);

  /* Create BB for body of the function and connect it properly.  */
  bb = create_basic_block (NULL, (void *) 0, ENTRY_BLOCK_PTR);
  make_edge (ENTRY_BLOCK_PTR, bb, 0);
  make_edge (bb, EXIT_BLOCK_PTR, 0);

  return bb;
}

/* Adjust PTR by the constant FIXED_OFFSET, and by the vtable
   offset indicated by VIRTUAL_OFFSET, if that is
   non-null. THIS_ADJUSTING is nonzero for a this adjusting thunk and
   zero for a result adjusting thunk.  */

static tree
thunk_adjust (gimple_stmt_iterator * bsi,
	      tree ptr, bool this_adjusting,
	      HOST_WIDE_INT fixed_offset, tree virtual_offset)
{
  gimple stmt;
  tree ret;

  if (this_adjusting
      && fixed_offset != 0)
    {
      stmt = gimple_build_assign (ptr,
				  fold_build2_loc (input_location,
						   POINTER_PLUS_EXPR,
						   TREE_TYPE (ptr), ptr,
						   size_int (fixed_offset)));
      gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
    }

  /* If there's a virtual offset, look up that value in the vtable and
     adjust the pointer again.  */
  if (virtual_offset)
    {
      tree vtabletmp;
      tree vtabletmp2;
      tree vtabletmp3;
      tree offsettmp;

      if (!vtable_entry_type)
	{
	  tree vfunc_type = make_node (FUNCTION_TYPE);
	  TREE_TYPE (vfunc_type) = integer_type_node;
	  TYPE_ARG_TYPES (vfunc_type) = NULL_TREE;
	  layout_type (vfunc_type);

	  vtable_entry_type = build_pointer_type (vfunc_type);
	}

      vtabletmp =
	create_tmp_var (build_pointer_type
			(build_pointer_type (vtable_entry_type)), "vptr");

      /* The vptr is always at offset zero in the object.  */
      stmt = gimple_build_assign (vtabletmp,
				  build1 (NOP_EXPR, TREE_TYPE (vtabletmp),
					  ptr));
      gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
      mark_symbols_for_renaming (stmt);
      find_referenced_vars_in (stmt);

      /* Form the vtable address.  */
      vtabletmp2 = create_tmp_var (TREE_TYPE (TREE_TYPE (vtabletmp)),
				   "vtableaddr");
      stmt = gimple_build_assign (vtabletmp2,
				  build_simple_mem_ref (vtabletmp));
      gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
      mark_symbols_for_renaming (stmt);
      find_referenced_vars_in (stmt);

      /* Find the entry with the vcall offset.  */
      stmt = gimple_build_assign (vtabletmp2,
				  fold_build2_loc (input_location,
						   POINTER_PLUS_EXPR,
						   TREE_TYPE (vtabletmp2),
						   vtabletmp2,
						   fold_convert (sizetype,
								 virtual_offset)));
      gsi_insert_after (bsi, stmt, GSI_NEW_STMT);

      /* Get the offset itself.  */
      vtabletmp3 = create_tmp_var (TREE_TYPE (TREE_TYPE (vtabletmp2)),
				   "vcalloffset");
      stmt = gimple_build_assign (vtabletmp3,
				  build_simple_mem_ref (vtabletmp2));
      gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
      mark_symbols_for_renaming (stmt);
      find_referenced_vars_in (stmt);

      /* Cast to sizetype.  */
      offsettmp = create_tmp_var (sizetype, "offset");
      stmt = gimple_build_assign (offsettmp, fold_convert (sizetype, vtabletmp3));
      gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
      mark_symbols_for_renaming (stmt);
      find_referenced_vars_in (stmt);

      /* Adjust the `this' pointer.  */
      ptr = fold_build2_loc (input_location,
			     POINTER_PLUS_EXPR, TREE_TYPE (ptr), ptr,
			     offsettmp);
    }

  if (!this_adjusting
      && fixed_offset != 0)
    /* Adjust the pointer by the constant.  */
    {
      tree ptrtmp;

      if (TREE_CODE (ptr) == VAR_DECL)
        ptrtmp = ptr;
      else
        {
          ptrtmp = create_tmp_var (TREE_TYPE (ptr), "ptr");
          stmt = gimple_build_assign (ptrtmp, ptr);
	  gsi_insert_after (bsi, stmt, GSI_NEW_STMT);
	  mark_symbols_for_renaming (stmt);
	  find_referenced_vars_in (stmt);
	}
      ptr = fold_build2_loc (input_location,
			     POINTER_PLUS_EXPR, TREE_TYPE (ptrtmp), ptrtmp,
			     size_int (fixed_offset));
    }

  /* Emit the statement and gimplify the adjustment expression.  */
  ret = create_tmp_var (TREE_TYPE (ptr), "adjusted_this");
  stmt = gimple_build_assign (ret, ptr);
  mark_symbols_for_renaming (stmt);
  find_referenced_vars_in (stmt);
  gsi_insert_after (bsi, stmt, GSI_NEW_STMT);

  return ret;
}

/* Produce assembler for thunk NODE.  */

static void
assemble_thunk (struct cgraph_node *node)
{
  bool this_adjusting = node->thunk.this_adjusting;
  HOST_WIDE_INT fixed_offset = node->thunk.fixed_offset;
  HOST_WIDE_INT virtual_value = node->thunk.virtual_value;
  tree virtual_offset = NULL;
  tree alias = node->thunk.alias;
  tree thunk_fndecl = node->decl;
  tree a = DECL_ARGUMENTS (thunk_fndecl);

  current_function_decl = thunk_fndecl;

  /* Ensure thunks are emitted in their correct sections.  */
  resolve_unique_section (thunk_fndecl, 0, flag_function_sections);

  if (this_adjusting
      && targetm.asm_out.can_output_mi_thunk (thunk_fndecl, fixed_offset,
					      virtual_value, alias))
    {
      const char *fnname;
      tree fn_block;
      
      DECL_RESULT (thunk_fndecl)
	= build_decl (DECL_SOURCE_LOCATION (thunk_fndecl),
		      RESULT_DECL, 0, integer_type_node);
      fnname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (thunk_fndecl));

      /* The back end expects DECL_INITIAL to contain a BLOCK, so we
	 create one.  */
      fn_block = make_node (BLOCK);
      BLOCK_VARS (fn_block) = a;
      DECL_INITIAL (thunk_fndecl) = fn_block;
      init_function_start (thunk_fndecl);
      cfun->is_thunk = 1;
      assemble_start_function (thunk_fndecl, fnname);

      targetm.asm_out.output_mi_thunk (asm_out_file, thunk_fndecl,
				       fixed_offset, virtual_value, alias);

      assemble_end_function (thunk_fndecl, fnname);
      init_insn_lengths ();
      free_after_compilation (cfun);
      set_cfun (NULL);
      TREE_ASM_WRITTEN (thunk_fndecl) = 1;
    }
  else
    {
      tree restype;
      basic_block bb, then_bb, else_bb, return_bb;
      gimple_stmt_iterator bsi;
      int nargs = 0;
      tree arg;
      int i;
      tree resdecl;
      tree restmp = NULL;
      VEC(tree, heap) *vargs;

      gimple call;
      gimple ret;

      DECL_IGNORED_P (thunk_fndecl) = 1;
      bitmap_obstack_initialize (NULL);

      if (node->thunk.virtual_offset_p)
        virtual_offset = size_int (virtual_value);

      /* Build the return declaration for the function.  */
      restype = TREE_TYPE (TREE_TYPE (thunk_fndecl));
      if (DECL_RESULT (thunk_fndecl) == NULL_TREE)
	{
	  resdecl = build_decl (input_location, RESULT_DECL, 0, restype);
	  DECL_ARTIFICIAL (resdecl) = 1;
	  DECL_IGNORED_P (resdecl) = 1;
	  DECL_RESULT (thunk_fndecl) = resdecl;
	}
      else
	resdecl = DECL_RESULT (thunk_fndecl);

      bb = then_bb = else_bb = return_bb = init_lowered_empty_function (thunk_fndecl);

      bsi = gsi_start_bb (bb);

      /* Build call to the function being thunked.  */
      if (!VOID_TYPE_P (restype))
	{
	  if (!is_gimple_reg_type (restype))
	    {
	      restmp = resdecl;
	      add_local_decl (cfun, restmp);
	      BLOCK_VARS (DECL_INITIAL (current_function_decl)) = restmp;
	    }
	  else
            restmp = create_tmp_var_raw (restype, "retval");
	}

      for (arg = a; arg; arg = DECL_CHAIN (arg))
        nargs++;
      vargs = VEC_alloc (tree, heap, nargs);
      if (this_adjusting)
        VEC_quick_push (tree, vargs,
			thunk_adjust (&bsi,
				      a, 1, fixed_offset,
				      virtual_offset));
      else
        VEC_quick_push (tree, vargs, a);
      for (i = 1, arg = DECL_CHAIN (a); i < nargs; i++, arg = DECL_CHAIN (arg))
        VEC_quick_push (tree, vargs, arg);
      call = gimple_build_call_vec (build_fold_addr_expr_loc (0, alias), vargs);
      VEC_free (tree, heap, vargs);
      gimple_call_set_cannot_inline (call, true);
      gimple_call_set_from_thunk (call, true);
      if (restmp)
        gimple_call_set_lhs (call, restmp);
      gsi_insert_after (&bsi, call, GSI_NEW_STMT);
      mark_symbols_for_renaming (call);
      find_referenced_vars_in (call);
      update_stmt (call);

      if (restmp && !this_adjusting)
        {
	  tree true_label = NULL_TREE;

	  if (TREE_CODE (TREE_TYPE (restmp)) == POINTER_TYPE)
	    {
	      gimple stmt;
	      /* If the return type is a pointer, we need to
		 protect against NULL.  We know there will be an
		 adjustment, because that's why we're emitting a
		 thunk.  */
	      then_bb = create_basic_block (NULL, (void *) 0, bb);
	      return_bb = create_basic_block (NULL, (void *) 0, then_bb);
	      else_bb = create_basic_block (NULL, (void *) 0, else_bb);
	      remove_edge (single_succ_edge (bb));
	      true_label = gimple_block_label (then_bb);
	      stmt = gimple_build_cond (NE_EXPR, restmp,
	      				build_zero_cst (TREE_TYPE (restmp)),
	      			        NULL_TREE, NULL_TREE);
	      gsi_insert_after (&bsi, stmt, GSI_NEW_STMT);
	      make_edge (bb, then_bb, EDGE_TRUE_VALUE);
	      make_edge (bb, else_bb, EDGE_FALSE_VALUE);
	      make_edge (return_bb, EXIT_BLOCK_PTR, 0);
	      make_edge (then_bb, return_bb, EDGE_FALLTHRU);
	      make_edge (else_bb, return_bb, EDGE_FALLTHRU);
	      bsi = gsi_last_bb (then_bb);
	    }

	  restmp = thunk_adjust (&bsi, restmp, /*this_adjusting=*/0,
			         fixed_offset, virtual_offset);
	  if (true_label)
	    {
	      gimple stmt;
	      bsi = gsi_last_bb (else_bb);
	      stmt = gimple_build_assign (restmp,
					  build_zero_cst (TREE_TYPE (restmp)));
	      gsi_insert_after (&bsi, stmt, GSI_NEW_STMT);
	      bsi = gsi_last_bb (return_bb);
	    }
	}
      else
        gimple_call_set_tail (call, true);

      /* Build return value.  */
      ret = gimple_build_return (restmp);
      gsi_insert_after (&bsi, ret, GSI_NEW_STMT);

      delete_unreachable_blocks ();
      update_ssa (TODO_update_ssa);

      cgraph_remove_same_body_alias (node);
      /* Since we want to emit the thunk, we explicitly mark its name as
	 referenced.  */
      cgraph_add_new_function (thunk_fndecl, true);
      bitmap_obstack_release (NULL);
    }
  current_function_decl = NULL;
}

/* Expand function specified by NODE.  */

static void
cgraph_expand_function (struct cgraph_node *node)
{
  tree decl = node->decl;

  /* We ought to not compile any inline clones.  */
  gcc_assert (!node->global.inlined_to);

  announce_function (decl);
  node->process = 0;
  if (node->same_body)
    {
      struct cgraph_node *alias, *next;
      bool saved_alias = node->alias;
      for (alias = node->same_body;
      	   alias && alias->next; alias = alias->next)
        ;
      /* Walk aliases in the order they were created; it is possible that
         thunks refers to the aliases made earlier.  */
      for (; alias; alias = next)
        {
	  next = alias->previous;
	  if (!alias->thunk.thunk_p)
	    assemble_alias (alias->decl,
			    DECL_ASSEMBLER_NAME (alias->thunk.alias));
	  else
	    assemble_thunk (alias);
	}
      node->alias = saved_alias;
      cgraph_process_new_functions ();
    }

  gcc_assert (node->lowered);

  /* Generate RTL for the body of DECL.  */
  tree_rest_of_compilation (decl);

  /* Make sure that BE didn't give up on compiling.  */
  gcc_assert (TREE_ASM_WRITTEN (decl));
  current_function_decl = NULL;
  gcc_assert (!cgraph_preserve_function_body_p (decl));
  cgraph_release_function_body (node);
  /* Eliminate all call edges.  This is important so the GIMPLE_CALL no longer
     points to the dead function body.  */
  cgraph_node_remove_callees (node);

  cgraph_function_flags_ready = true;
}

/* Return true when CALLER_DECL should be inlined into CALLEE_DECL.  */

bool
cgraph_inline_p (struct cgraph_edge *e, cgraph_inline_failed_t *reason)
{
  *reason = e->inline_failed;
  return !e->inline_failed;
}



/* Expand all functions that must be output.

   Attempt to topologically sort the nodes so function is output when
   all called functions are already assembled to allow data to be
   propagated across the callgraph.  Use a stack to get smaller distance
   between a function and its callees (later we may choose to use a more
   sophisticated algorithm for function reordering; we will likely want
   to use subsections to make the output functions appear in top-down
   order).  */

static void
cgraph_expand_all_functions (void)
{
  struct cgraph_node *node;
  struct cgraph_node **order = XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
  int order_pos, new_order_pos = 0;
  int i;

  order_pos = cgraph_postorder (order);
  gcc_assert (order_pos == cgraph_n_nodes);

  /* Garbage collector may remove inline clones we eliminate during
     optimization.  So we must be sure to not reference them.  */
  for (i = 0; i < order_pos; i++)
    if (order[i]->process)
      order[new_order_pos++] = order[i];

  for (i = new_order_pos - 1; i >= 0; i--)
    {
      node = order[i];
      if (node->process)
	{
	  gcc_assert (node->reachable);
	  node->process = 0;
	  cgraph_expand_function (node);
	}
    }
  cgraph_process_new_functions ();

  free (order);

}

/* This is used to sort the node types by the cgraph order number.  */

enum cgraph_order_sort_kind
{
  ORDER_UNDEFINED = 0,
  ORDER_FUNCTION,
  ORDER_VAR,
  ORDER_ASM
};

struct cgraph_order_sort
{
  enum cgraph_order_sort_kind kind;
  union
  {
    struct cgraph_node *f;
    struct varpool_node *v;
    struct cgraph_asm_node *a;
  } u;
};

/* Output all functions, variables, and asm statements in the order
   according to their order fields, which is the order in which they
   appeared in the file.  This implements -fno-toplevel-reorder.  In
   this mode we may output functions and variables which don't really
   need to be output.  */

static void
cgraph_output_in_order (void)
{
  int max;
  struct cgraph_order_sort *nodes;
  int i;
  struct cgraph_node *pf;
  struct varpool_node *pv;
  struct cgraph_asm_node *pa;

  max = cgraph_order;
  nodes = XCNEWVEC (struct cgraph_order_sort, max);

  varpool_analyze_pending_decls ();

  for (pf = cgraph_nodes; pf; pf = pf->next)
    {
      if (pf->process)
	{
	  i = pf->order;
	  gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
	  nodes[i].kind = ORDER_FUNCTION;
	  nodes[i].u.f = pf;
	}
    }

  for (pv = varpool_nodes_queue; pv; pv = pv->next_needed)
    {
      i = pv->order;
      gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
      nodes[i].kind = ORDER_VAR;
      nodes[i].u.v = pv;
    }

  for (pa = cgraph_asm_nodes; pa; pa = pa->next)
    {
      i = pa->order;
      gcc_assert (nodes[i].kind == ORDER_UNDEFINED);
      nodes[i].kind = ORDER_ASM;
      nodes[i].u.a = pa;
    }

  /* In toplevel reorder mode we output all statics; mark them as needed.  */
  for (i = 0; i < max; ++i)
    {
      if (nodes[i].kind == ORDER_VAR)
        {
	  varpool_mark_needed_node (nodes[i].u.v);
	}
    }
  varpool_empty_needed_queue ();

  for (i = 0; i < max; ++i)
    if (nodes[i].kind == ORDER_VAR)
      varpool_finalize_named_section_flags (nodes[i].u.v);

  for (i = 0; i < max; ++i)
    {
      switch (nodes[i].kind)
	{
	case ORDER_FUNCTION:
	  nodes[i].u.f->process = 0;
	  cgraph_expand_function (nodes[i].u.f);
	  break;

	case ORDER_VAR:
	  varpool_assemble_decl (nodes[i].u.v);
	  break;

	case ORDER_ASM:
	  assemble_asm (nodes[i].u.a->asm_str);
	  break;

	case ORDER_UNDEFINED:
	  break;

	default:
	  gcc_unreachable ();
	}
    }

  cgraph_asm_nodes = NULL;
  free (nodes);
}

/* Return true when function body of DECL still needs to be kept around
   for later re-use.  */
bool
cgraph_preserve_function_body_p (tree decl)
{
  struct cgraph_node *node;

  gcc_assert (cgraph_global_info_ready);
  /* Look if there is any clone around.  */
  node = cgraph_node (decl);
  if (node->clones)
    return true;
  return false;
}

static void
ipa_passes (void)
{
  set_cfun (NULL);
  current_function_decl = NULL;
  gimple_register_cfg_hooks ();
  bitmap_obstack_initialize (NULL);

  invoke_plugin_callbacks (PLUGIN_ALL_IPA_PASSES_START, NULL);

  if (!in_lto_p)
    {
      execute_ipa_pass_list (all_small_ipa_passes);
      if (seen_error ())
	return;
    }

  /* If pass_all_early_optimizations was not scheduled, the state of
     the cgraph will not be properly updated.  Update it now.  */
  if (cgraph_state < CGRAPH_STATE_IPA_SSA)
    cgraph_state = CGRAPH_STATE_IPA_SSA;

  if (!in_lto_p)
    {
      /* Generate coverage variables and constructors.  */
      coverage_finish ();

      /* Process new functions added.  */
      set_cfun (NULL);
      current_function_decl = NULL;
      cgraph_process_new_functions ();

      execute_ipa_summary_passes
	((struct ipa_opt_pass_d *) all_regular_ipa_passes);
    }

  /* Some targets need to handle LTO assembler output specially.  */
  if (flag_generate_lto)
    targetm.asm_out.lto_start ();

  execute_ipa_summary_passes ((struct ipa_opt_pass_d *) all_lto_gen_passes);

  if (!in_lto_p)
    ipa_write_summaries ();

  if (flag_generate_lto)
    targetm.asm_out.lto_end ();

  if (!flag_ltrans)
    execute_ipa_pass_list (all_regular_ipa_passes);
  invoke_plugin_callbacks (PLUGIN_ALL_IPA_PASSES_END, NULL);

  bitmap_obstack_release (NULL);
}


/* Perform simple optimizations based on callgraph.  */

void
cgraph_optimize (void)
{
  if (seen_error ())
    return;

#ifdef ENABLE_CHECKING
  verify_cgraph ();
#endif

  /* Frontend may output common variables after the unit has been finalized.
     It is safe to deal with them here as they are always zero initialized.  */
  varpool_analyze_pending_decls ();

  timevar_push (TV_CGRAPHOPT);
  if (pre_ipa_mem_report)
    {
      fprintf (stderr, "Memory consumption before IPA\n");
      dump_memory_report (false);
    }
  if (!quiet_flag)
    fprintf (stderr, "Performing interprocedural optimizations\n");
  cgraph_state = CGRAPH_STATE_IPA;

  /* Don't run the IPA passes if there was any error or sorry messages.  */
  if (!seen_error ())
    ipa_passes ();

  /* Do nothing else if any IPA pass found errors.  */
  if (seen_error ())
    {
      timevar_pop (TV_CGRAPHOPT);
      return;
    }

  /* This pass remove bodies of extern inline functions we never inlined.
     Do this later so other IPA passes see what is really going on.  */
  cgraph_remove_unreachable_nodes (false, dump_file);
  cgraph_global_info_ready = true;
  if (cgraph_dump_file)
    {
      fprintf (cgraph_dump_file, "Optimized ");
      dump_cgraph (cgraph_dump_file);
      dump_varpool (cgraph_dump_file);
    }
  if (post_ipa_mem_report)
    {
      fprintf (stderr, "Memory consumption after IPA\n");
      dump_memory_report (false);
    }
  timevar_pop (TV_CGRAPHOPT);

  /* Output everything.  */
  (*debug_hooks->assembly_start) ();
  if (!quiet_flag)
    fprintf (stderr, "Assembling functions:\n");
#ifdef ENABLE_CHECKING
  verify_cgraph ();
#endif

  cgraph_materialize_all_clones ();
  cgraph_mark_functions_to_output ();

  cgraph_state = CGRAPH_STATE_EXPANSION;
  if (!flag_toplevel_reorder)
    cgraph_output_in_order ();
  else
    {
      cgraph_output_pending_asms ();

      cgraph_expand_all_functions ();
      varpool_remove_unreferenced_decls ();

      varpool_assemble_pending_decls ();
    }
  cgraph_process_new_functions ();
  cgraph_state = CGRAPH_STATE_FINISHED;

  if (cgraph_dump_file)
    {
      fprintf (cgraph_dump_file, "\nFinal ");
      dump_cgraph (cgraph_dump_file);
      dump_varpool (cgraph_dump_file);
    }
#ifdef ENABLE_CHECKING
  verify_cgraph ();
  /* Double check that all inline clones are gone and that all
     function bodies have been released from memory.  */
  if (!seen_error ())
    {
      struct cgraph_node *node;
      bool error_found = false;

      for (node = cgraph_nodes; node; node = node->next)
	if (node->analyzed
	    && (node->global.inlined_to
		|| gimple_has_body_p (node->decl)))
	  {
	    error_found = true;
	    dump_cgraph_node (stderr, node);
	  }
      if (error_found)
	internal_error ("nodes with unreleased memory found");
    }
#endif
}

void
init_cgraph (void)
{
  if (!cgraph_dump_file)
    cgraph_dump_file = dump_begin (TDI_cgraph, NULL);
}

/* The edges representing the callers of the NEW_VERSION node were
   fixed by cgraph_function_versioning (), now the call_expr in their
   respective tree code should be updated to call the NEW_VERSION.  */

static void
update_call_expr (struct cgraph_node *new_version)
{
  struct cgraph_edge *e;

  gcc_assert (new_version);

  /* Update the call expr on the edges to call the new version.  */
  for (e = new_version->callers; e; e = e->next_caller)
    {
      struct function *inner_function = DECL_STRUCT_FUNCTION (e->caller->decl);
      gimple_call_set_fndecl (e->call_stmt, new_version->decl);
      maybe_clean_eh_stmt_fn (inner_function, e->call_stmt);
    }
}


/* Create a new cgraph node which is the new version of
   OLD_VERSION node.  REDIRECT_CALLERS holds the callers
   edges which should be redirected to point to
   NEW_VERSION.  ALL the callees edges of OLD_VERSION
   are cloned to the new version node.  Return the new
   version node. 

   If non-NULL BLOCK_TO_COPY determine what basic blocks 
   was copied to prevent duplications of calls that are dead
   in the clone.  */

static struct cgraph_node *
cgraph_copy_node_for_versioning (struct cgraph_node *old_version,
				 tree new_decl,
				 VEC(cgraph_edge_p,heap) *redirect_callers,
				 bitmap bbs_to_copy)
 {
   struct cgraph_node *new_version;
   struct cgraph_edge *e;
   unsigned i;

   gcc_assert (old_version);

   new_version = cgraph_node (new_decl);

   new_version->analyzed = true;
   new_version->local = old_version->local;
   new_version->local.externally_visible = false;
   new_version->local.local = true;
   new_version->local.vtable_method = false;
   new_version->global = old_version->global;
   new_version->rtl = old_version->rtl;
   new_version->reachable = true;
   new_version->count = old_version->count;

   for (e = old_version->callees; e; e=e->next_callee)
     if (!bbs_to_copy
	 || bitmap_bit_p (bbs_to_copy, gimple_bb (e->call_stmt)->index))
       cgraph_clone_edge (e, new_version, e->call_stmt,
			  e->lto_stmt_uid, REG_BR_PROB_BASE,
			  CGRAPH_FREQ_BASE,
			  e->loop_nest, true);
   for (e = old_version->indirect_calls; e; e=e->next_callee)
     if (!bbs_to_copy
	 || bitmap_bit_p (bbs_to_copy, gimple_bb (e->call_stmt)->index))
       cgraph_clone_edge (e, new_version, e->call_stmt,
			  e->lto_stmt_uid, REG_BR_PROB_BASE,
			  CGRAPH_FREQ_BASE,
			  e->loop_nest, true);
   FOR_EACH_VEC_ELT (cgraph_edge_p, redirect_callers, i, e)
     {
       /* Redirect calls to the old version node to point to its new
	  version.  */
       cgraph_redirect_edge_callee (e, new_version);
     }

   return new_version;
 }

 /* Perform function versioning.
    Function versioning includes copying of the tree and
    a callgraph update (creating a new cgraph node and updating
    its callees and callers).

    REDIRECT_CALLERS varray includes the edges to be redirected
    to the new version.

    TREE_MAP is a mapping of tree nodes we want to replace with
    new ones (according to results of prior analysis).
    OLD_VERSION_NODE is the node that is versioned.
    It returns the new version's cgraph node.
    If non-NULL ARGS_TO_SKIP determine function parameters to remove
    from new version.
    If non-NULL BLOCK_TO_COPY determine what basic blocks to copy.
    If non_NULL NEW_ENTRY determine new entry BB of the clone.  */

struct cgraph_node *
cgraph_function_versioning (struct cgraph_node *old_version_node,
			    VEC(cgraph_edge_p,heap) *redirect_callers,
			    VEC (ipa_replace_map_p,gc)* tree_map,
			    bitmap args_to_skip,
			    bitmap bbs_to_copy,
			    basic_block new_entry_block,
			    const char *clone_name)
{
  tree old_decl = old_version_node->decl;
  struct cgraph_node *new_version_node = NULL;
  tree new_decl;

  if (!tree_versionable_function_p (old_decl))
    return NULL;

  gcc_assert (old_version_node->local.can_change_signature || !args_to_skip);

  /* Make a new FUNCTION_DECL tree node for the
     new version. */
  if (!args_to_skip)
    new_decl = copy_node (old_decl);
  else
    new_decl = build_function_decl_skip_args (old_decl, args_to_skip);

  /* Generate a new name for the new version. */
  DECL_NAME (new_decl) = clone_function_name (old_decl, clone_name);
  SET_DECL_ASSEMBLER_NAME (new_decl, DECL_NAME (new_decl));
  SET_DECL_RTL (new_decl, NULL);

  /* Create the new version's call-graph node.
     and update the edges of the new node. */
  new_version_node =
    cgraph_copy_node_for_versioning (old_version_node, new_decl,
				     redirect_callers, bbs_to_copy);

  /* Copy the OLD_VERSION_NODE function tree to the new version.  */
  tree_function_versioning (old_decl, new_decl, tree_map, false, args_to_skip,
			    bbs_to_copy, new_entry_block);

  /* Update the new version's properties.
     Make The new version visible only within this translation unit.  Make sure
     that is not weak also.
     ??? We cannot use COMDAT linkage because there is no
     ABI support for this.  */
  cgraph_make_decl_local (new_version_node->decl);
  DECL_VIRTUAL_P (new_version_node->decl) = 0;
  new_version_node->local.externally_visible = 0;
  new_version_node->local.local = 1;
  new_version_node->lowered = true;

  /* Update the call_expr on the edges to call the new version node. */
  update_call_expr (new_version_node);

  cgraph_call_function_insertion_hooks (new_version_node);
  return new_version_node;
}

/* Produce separate function body for inline clones so the offline copy can be
   modified without affecting them.  */
struct cgraph_node *
save_inline_function_body (struct cgraph_node *node)
{
  struct cgraph_node *first_clone, *n;

  gcc_assert (node == cgraph_node (node->decl));

  cgraph_lower_function (node);

  first_clone = node->clones;

  first_clone->decl = copy_node (node->decl);
  cgraph_insert_node_to_hashtable (first_clone);
  gcc_assert (first_clone == cgraph_node (first_clone->decl));
  if (first_clone->next_sibling_clone)
    {
      for (n = first_clone->next_sibling_clone; n->next_sibling_clone; n = n->next_sibling_clone)
        n->clone_of = first_clone;
      n->clone_of = first_clone;
      n->next_sibling_clone = first_clone->clones;
      if (first_clone->clones)
        first_clone->clones->prev_sibling_clone = n;
      first_clone->clones = first_clone->next_sibling_clone;
      first_clone->next_sibling_clone->prev_sibling_clone = NULL;
      first_clone->next_sibling_clone = NULL;
      gcc_assert (!first_clone->prev_sibling_clone);
    }
  first_clone->clone_of = NULL;
  node->clones = NULL;

  if (first_clone->clones)
    for (n = first_clone->clones; n != first_clone;)
      {
        gcc_assert (n->decl == node->decl);
	n->decl = first_clone->decl;
	if (n->clones)
	  n = n->clones;
	else if (n->next_sibling_clone)
	  n = n->next_sibling_clone;
	else
	  {
	    while (n != first_clone && !n->next_sibling_clone)
	      n = n->clone_of;
	    if (n != first_clone)
	      n = n->next_sibling_clone;
	  }
      }

  /* Copy the OLD_VERSION_NODE function tree to the new version.  */
  tree_function_versioning (node->decl, first_clone->decl, NULL, true, NULL,
			    NULL, NULL);

  DECL_EXTERNAL (first_clone->decl) = 0;
  DECL_COMDAT_GROUP (first_clone->decl) = NULL_TREE;
  TREE_PUBLIC (first_clone->decl) = 0;
  DECL_COMDAT (first_clone->decl) = 0;
  VEC_free (ipa_opt_pass, heap,
            first_clone->ipa_transforms_to_apply);
  first_clone->ipa_transforms_to_apply = NULL;

#ifdef ENABLE_CHECKING
  verify_cgraph_node (first_clone);
#endif
  return first_clone;
}

/* Given virtual clone, turn it into actual clone.  */
static void
cgraph_materialize_clone (struct cgraph_node *node)
{
  bitmap_obstack_initialize (NULL);
  node->former_clone_of = node->clone_of->decl;
  if (node->clone_of->former_clone_of)
    node->former_clone_of = node->clone_of->former_clone_of;
  /* Copy the OLD_VERSION_NODE function tree to the new version.  */
  tree_function_versioning (node->clone_of->decl, node->decl,
  			    node->clone.tree_map, true,
			    node->clone.args_to_skip, NULL, NULL);
  if (cgraph_dump_file)
    {
      dump_function_to_file (node->clone_of->decl, cgraph_dump_file, dump_flags);
      dump_function_to_file (node->decl, cgraph_dump_file, dump_flags);
    }

  /* Function is no longer clone.  */
  if (node->next_sibling_clone)
    node->next_sibling_clone->prev_sibling_clone = node->prev_sibling_clone;
  if (node->prev_sibling_clone)
    node->prev_sibling_clone->next_sibling_clone = node->next_sibling_clone;
  else
    node->clone_of->clones = node->next_sibling_clone;
  node->next_sibling_clone = NULL;
  node->prev_sibling_clone = NULL;
  if (!node->clone_of->analyzed && !node->clone_of->clones)
    {
      cgraph_release_function_body (node->clone_of);
      cgraph_node_remove_callees (node->clone_of);
      ipa_remove_all_references (&node->clone_of->ref_list);
    }
  node->clone_of = NULL;
  bitmap_obstack_release (NULL);
}

/* If necessary, change the function declaration in the call statement
   associated with E so that it corresponds to the edge callee.  */

gimple
cgraph_redirect_edge_call_stmt_to_callee (struct cgraph_edge *e)
{
  tree decl = gimple_call_fndecl (e->call_stmt);
  gimple new_stmt;
  gimple_stmt_iterator gsi;
  bool gsi_computed = false;
#ifdef ENABLE_CHECKING
  struct cgraph_node *node;
#endif

  if (e->indirect_unknown_callee
      || decl == e->callee->decl
      /* Don't update call from same body alias to the real function.  */
      || (decl && cgraph_get_node (decl) == cgraph_get_node (e->callee->decl)))
    return e->call_stmt;

#ifdef ENABLE_CHECKING
  if (decl)
    {
      node = cgraph_get_node (decl);
      gcc_assert (!node || !node->clone.combined_args_to_skip);
    }
#endif

  if (cgraph_dump_file)
    {
      fprintf (cgraph_dump_file, "updating call of %s/%i -> %s/%i: ",
	       cgraph_node_name (e->caller), e->caller->uid,
	       cgraph_node_name (e->callee), e->callee->uid);
      print_gimple_stmt (cgraph_dump_file, e->call_stmt, 0, dump_flags);
      if (e->callee->clone.combined_args_to_skip)
	{
	  fprintf (cgraph_dump_file, " combined args to skip: ");
	  dump_bitmap (cgraph_dump_file,
		       e->callee->clone.combined_args_to_skip);
	}
    }

  if (e->indirect_info &&
      e->indirect_info->thunk_delta != 0
      && (!e->callee->clone.combined_args_to_skip
	  || !bitmap_bit_p (e->callee->clone.combined_args_to_skip, 0)))
    {
      if (cgraph_dump_file)
	fprintf (cgraph_dump_file, "          Thunk delta is "
		 HOST_WIDE_INT_PRINT_DEC "\n", e->indirect_info->thunk_delta);
      gsi = gsi_for_stmt (e->call_stmt);
      gsi_computed = true;
      gimple_adjust_this_by_delta (&gsi,
				   build_int_cst (sizetype,
					       e->indirect_info->thunk_delta));
      e->indirect_info->thunk_delta = 0;
    }

  if (e->callee->clone.combined_args_to_skip)
    {
      int lp_nr;

      new_stmt
	= gimple_call_copy_skip_args (e->call_stmt,
				      e->callee->clone.combined_args_to_skip);
      gimple_call_set_fndecl (new_stmt, e->callee->decl);

      if (gimple_vdef (new_stmt)
	  && TREE_CODE (gimple_vdef (new_stmt)) == SSA_NAME)
	SSA_NAME_DEF_STMT (gimple_vdef (new_stmt)) = new_stmt;

      if (!gsi_computed)
	gsi = gsi_for_stmt (e->call_stmt);
      gsi_replace (&gsi, new_stmt, false);
      /* We need to defer cleaning EH info on the new statement to
         fixup-cfg.  We may not have dominator information at this point
	 and thus would end up with unreachable blocks and have no way
	 to communicate that we need to run CFG cleanup then.  */
      lp_nr = lookup_stmt_eh_lp (e->call_stmt);
      if (lp_nr != 0)
	{
	  remove_stmt_from_eh_lp (e->call_stmt);
	  add_stmt_to_eh_lp (new_stmt, lp_nr);
	}
    }
  else
    {
      new_stmt = e->call_stmt;
      gimple_call_set_fndecl (new_stmt, e->callee->decl);
      update_stmt (new_stmt);
    }

  cgraph_set_call_stmt_including_clones (e->caller, e->call_stmt, new_stmt);

  if (cgraph_dump_file)
    {
      fprintf (cgraph_dump_file, "  updated to:");
      print_gimple_stmt (cgraph_dump_file, e->call_stmt, 0, dump_flags);
    }
  return new_stmt;
}

/* Once all functions from compilation unit are in memory, produce all clones
   and update all calls.  We might also do this on demand if we don't want to
   bring all functions to memory prior compilation, but current WHOPR
   implementation does that and it is is bit easier to keep everything right in
   this order.  */
void
cgraph_materialize_all_clones (void)
{
  struct cgraph_node *node;
  bool stabilized = false;

  if (cgraph_dump_file)
    fprintf (cgraph_dump_file, "Materializing clones\n");
#ifdef ENABLE_CHECKING
  verify_cgraph ();
#endif

  /* We can also do topological order, but number of iterations should be
     bounded by number of IPA passes since single IPA pass is probably not
     going to create clones of clones it created itself.  */
  while (!stabilized)
    {
      stabilized = true;
      for (node = cgraph_nodes; node; node = node->next)
        {
	  if (node->clone_of && node->decl != node->clone_of->decl
	      && !gimple_has_body_p (node->decl))
	    {
	      if (gimple_has_body_p (node->clone_of->decl))
	        {
		  if (cgraph_dump_file)
		    {
		      fprintf (cgraph_dump_file, "cloning %s to %s\n",
			       cgraph_node_name (node->clone_of),
			       cgraph_node_name (node));
		      if (node->clone.tree_map)
		        {
			  unsigned int i;
		          fprintf (cgraph_dump_file, "   replace map: ");
			  for (i = 0; i < VEC_length (ipa_replace_map_p,
			  			      node->clone.tree_map);
						      i++)
			    {
			      struct ipa_replace_map *replace_info;
			      replace_info = VEC_index (ipa_replace_map_p,
			      				node->clone.tree_map,
							i);
			      print_generic_expr (cgraph_dump_file, replace_info->old_tree, 0);
			      fprintf (cgraph_dump_file, " -> ");
			      print_generic_expr (cgraph_dump_file, replace_info->new_tree, 0);
			      fprintf (cgraph_dump_file, "%s%s;",
			      	       replace_info->replace_p ? "(replace)":"",
				       replace_info->ref_p ? "(ref)":"");
			    }
			  fprintf (cgraph_dump_file, "\n");
			}
		      if (node->clone.args_to_skip)
			{
		          fprintf (cgraph_dump_file, "   args_to_skip: ");
		          dump_bitmap (cgraph_dump_file, node->clone.args_to_skip);
			}
		      if (node->clone.args_to_skip)
			{
		          fprintf (cgraph_dump_file, "   combined_args_to_skip:");
		          dump_bitmap (cgraph_dump_file, node->clone.combined_args_to_skip);
			}
		    }
		  cgraph_materialize_clone (node);
		  stabilized = false;
	        }
	    }
	}
    }
  for (node = cgraph_nodes; node; node = node->next)
    if (!node->analyzed && node->callees)
      cgraph_node_remove_callees (node);
  if (cgraph_dump_file)
    fprintf (cgraph_dump_file, "Materialization Call site updates done.\n");
#ifdef ENABLE_CHECKING
  verify_cgraph ();
#endif
  cgraph_remove_unreachable_nodes (false, cgraph_dump_file);
}

#include "gt-cgraphunit.h"