aboutsummaryrefslogtreecommitdiffstats
path: root/src/vppinfra/dlmalloc.c
blob: e01ac94b8c018501e8c55c9dda72e4814c3dc616 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
/*
  This is a version (aka dlmalloc) of malloc/free/realloc written by
  Doug Lea and released to the public domain, as explained at
  http://creativecommons.org/publicdomain/zero/1.0/ Send questions,
  comments, complaints, performance data, etc to dl@cs.oswego.edu
*/

#include <vppinfra/dlmalloc.h>
#include <vppinfra/sanitizer.h>

/*------------------------------ internal #includes ---------------------- */

#ifdef _MSC_VER
#pragma warning( disable : 4146 ) /* no "unsigned" warnings */
#endif /* _MSC_VER */
#if !NO_MALLOC_STATS
#include <stdio.h>       /* for printing in malloc_stats */
#endif /* NO_MALLOC_STATS */
#ifndef LACKS_ERRNO_H
#include <errno.h>       /* for MALLOC_FAILURE_ACTION */
#endif /* LACKS_ERRNO_H */
#ifdef DEBUG
#if DLM_ABORT_ON_ASSERT_FAILURE
#undef assert
#define assert(x) if(!(x)) DLM_ABORT
#else /* DLM_ABORT_ON_ASSERT_FAILURE */
#include <assert.h>
#endif /* DLM_ABORT_ON_ASSERT_FAILURE */
#else  /* DEBUG */
#ifndef assert
#define assert(x)
#endif
#define DEBUG 0
#endif /* DEBUG */
#if !defined(WIN32) && !defined(LACKS_TIME_H)
#include <time.h>        /* for magic initialization */
#endif /* WIN32 */
#ifndef LACKS_STDLIB_H
#include <stdlib.h>      /* for abort() */
#endif /* LACKS_STDLIB_H */
#ifndef LACKS_STRING_H
#include <string.h>      /* for memset etc */
#endif  /* LACKS_STRING_H */
#if USE_BUILTIN_FFS
#ifndef LACKS_STRINGS_H
#include <strings.h>     /* for ffs */
#endif /* LACKS_STRINGS_H */
#endif /* USE_BUILTIN_FFS */
#if HAVE_MMAP
#ifndef LACKS_SYS_MMAN_H
/* On some versions of linux, mremap decl in mman.h needs __USE_GNU set */
#if (defined(linux) && !defined(__USE_GNU))
#define __USE_GNU 1
#include <sys/mman.h>    /* for mmap */
#undef __USE_GNU
#else
#include <sys/mman.h>    /* for mmap */
#endif /* linux */
#endif /* LACKS_SYS_MMAN_H */
#ifndef LACKS_FCNTL_H
#include <fcntl.h>
#endif /* LACKS_FCNTL_H */
#endif /* HAVE_MMAP */
#ifndef LACKS_UNISTD_H
#include <unistd.h>     /* for sbrk, sysconf */
#else /* LACKS_UNISTD_H */
#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
extern void*     sbrk(ptrdiff_t);
#endif /* FreeBSD etc */
#endif /* LACKS_UNISTD_H */

/* Declarations for locking */
#if USE_LOCKS
#ifndef WIN32
#if defined (__SVR4) && defined (__sun)  /* solaris */
#include <thread.h>
#elif !defined(LACKS_SCHED_H)
#include <sched.h>
#endif /* solaris or LACKS_SCHED_H */
#if (defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0) || !USE_SPIN_LOCKS
#include <pthread.h>
#endif /* USE_RECURSIVE_LOCKS ... */
#elif defined(_MSC_VER)
#ifndef _M_AMD64
/* These are already defined on AMD64 builds */
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
LONG __cdecl _InterlockedCompareExchange(LONG volatile *Dest, LONG Exchange, LONG Comp);
LONG __cdecl _InterlockedExchange(LONG volatile *Target, LONG Value);
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* _M_AMD64 */
#pragma intrinsic (_InterlockedCompareExchange)
#pragma intrinsic (_InterlockedExchange)
#define interlockedcompareexchange _InterlockedCompareExchange
#define interlockedexchange _InterlockedExchange
#elif defined(WIN32) && defined(__GNUC__)
#define interlockedcompareexchange(a, b, c) __sync_val_compare_and_swap(a, c, b)
#define interlockedexchange __sync_lock_test_and_set
#endif /* Win32 */
#else /* USE_LOCKS */
#endif /* USE_LOCKS */

#ifndef LOCK_AT_FORK
#define LOCK_AT_FORK 0
#endif

/* Declarations for bit scanning on win32 */
#if defined(_MSC_VER) && _MSC_VER>=1300
#ifndef BitScanForward /* Try to avoid pulling in WinNT.h */
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
unsigned char _BitScanForward(unsigned long *index, unsigned long mask);
unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);
#ifdef __cplusplus
}
#endif /* __cplusplus */

#define BitScanForward _BitScanForward
#define BitScanReverse _BitScanReverse
#pragma intrinsic(_BitScanForward)
#pragma intrinsic(_BitScanReverse)
#endif /* BitScanForward */
#endif /* defined(_MSC_VER) && _MSC_VER>=1300 */

#ifndef WIN32
#ifndef malloc_getpagesize
#  ifdef _SC_PAGESIZE         /* some SVR4 systems omit an underscore */
#    ifndef _SC_PAGE_SIZE
#      define _SC_PAGE_SIZE _SC_PAGESIZE
#    endif
#  endif
#  ifdef _SC_PAGE_SIZE
#    define malloc_getpagesize sysconf(_SC_PAGE_SIZE)
#  else
#    if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE)
       extern size_t getpagesize();
#      define malloc_getpagesize getpagesize()
#    else
#      ifdef WIN32 /* use supplied emulation of getpagesize */
#        define malloc_getpagesize getpagesize()
#      else
#        ifndef LACKS_SYS_PARAM_H
#          include <sys/param.h>
#        endif
#        ifdef EXEC_PAGESIZE
#          define malloc_getpagesize EXEC_PAGESIZE
#        else
#          ifdef NBPG
#            ifndef CLSIZE
#              define malloc_getpagesize NBPG
#            else
#              define malloc_getpagesize (NBPG * CLSIZE)
#            endif
#          else
#            ifdef NBPC
#              define malloc_getpagesize NBPC
#            else
#              ifdef PAGESIZE
#                define malloc_getpagesize PAGESIZE
#              else /* just guess */
#                define malloc_getpagesize ((size_t)4096U)
#              endif
#            endif
#          endif
#        endif
#      endif
#    endif
#  endif
#endif
#endif

/* ------------------- size_t and alignment properties -------------------- */

/* The byte and bit size of a size_t */
#define SIZE_T_SIZE         (sizeof(size_t))
#define SIZE_T_BITSIZE      (sizeof(size_t) << 3)

/* Some constants coerced to size_t */
/* Annoying but necessary to avoid errors on some platforms */
#define SIZE_T_ZERO         ((size_t)0)
#define SIZE_T_ONE          ((size_t)1)
#define SIZE_T_TWO          ((size_t)2)
#define SIZE_T_FOUR         ((size_t)4)
#define TWO_SIZE_T_SIZES    (SIZE_T_SIZE<<1)
#define FOUR_SIZE_T_SIZES   (SIZE_T_SIZE<<2)
#define SIX_SIZE_T_SIZES    (FOUR_SIZE_T_SIZES+TWO_SIZE_T_SIZES)
#define HALF_MAX_SIZE_T     (MAX_SIZE_T / 2U)

/* The bit mask value corresponding to MALLOC_ALIGNMENT */
#define CHUNK_ALIGN_MASK    (MALLOC_ALIGNMENT - SIZE_T_ONE)

/* True if address a has acceptable alignment */
#define is_aligned(A)       (((size_t)((A)) & (CHUNK_ALIGN_MASK)) == 0)

/* the number of bytes to offset an address to align it */
#define align_offset(A)\
 ((((size_t)(A) & CHUNK_ALIGN_MASK) == 0)? 0 :\
  ((MALLOC_ALIGNMENT - ((size_t)(A) & CHUNK_ALIGN_MASK)) & CHUNK_ALIGN_MASK))

/* -------------------------- MMAP preliminaries ------------------------- */

/*
   If HAVE_MORECORE or HAVE_MMAP are false, we just define calls and
   checks to fail so compiler optimizer can delete code rather than
   using so many "#if"s.
*/


/* MORECORE and MMAP must return MFAIL on failure */
#define MFAIL                ((void*)(MAX_SIZE_T))
#define CMFAIL               ((char*)(MFAIL)) /* defined for convenience */

#if HAVE_MMAP

#ifndef WIN32
#define MUNMAP_DEFAULT(a, s)  munmap((a), (s))
#define MMAP_PROT            (PROT_READ|PROT_WRITE)
#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
#define MAP_ANONYMOUS        MAP_ANON
#endif /* MAP_ANON */
#ifdef MAP_ANONYMOUS
#define MMAP_FLAGS           (MAP_PRIVATE|MAP_ANONYMOUS)
#define MMAP_DEFAULT(s)       mmap(0, (s), MMAP_PROT, MMAP_FLAGS, -1, 0)
#else /* MAP_ANONYMOUS */
/*
   Nearly all versions of mmap support MAP_ANONYMOUS, so the following
   is unlikely to be needed, but is supplied just in case.
*/
#define MMAP_FLAGS           (MAP_PRIVATE)
static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */
#define MMAP_DEFAULT(s) ((dev_zero_fd < 0) ? \
           (dev_zero_fd = open("/dev/zero", O_RDWR), \
            mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0)) : \
            mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0))
#endif /* MAP_ANONYMOUS */

#define DIRECT_MMAP_DEFAULT(s) MMAP_DEFAULT(s)

#else /* WIN32 */

/* Win32 MMAP via VirtualAlloc */
static FORCEINLINE void* win32mmap(size_t size) {
  void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
  return (ptr != 0)? ptr: MFAIL;
}

/* For direct MMAP, use MEM_TOP_DOWN to minimize interference */
static FORCEINLINE void* win32direct_mmap(size_t size) {
  void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN,
                           PAGE_READWRITE);
  return (ptr != 0)? ptr: MFAIL;
}

/* This function supports releasing coalesed segments */
static FORCEINLINE int win32munmap(void* ptr, size_t size) {
  MEMORY_BASIC_INFORMATION minfo;
  char* cptr = (char*)ptr;
  while (size) {
    if (VirtualQuery(cptr, &minfo, sizeof(minfo)) == 0)
      return -1;
    if (minfo.BaseAddress != cptr || minfo.AllocationBase != cptr ||
        minfo.State != MEM_COMMIT || minfo.RegionSize > size)
      return -1;
    if (VirtualFree(cptr, 0, MEM_RELEASE) == 0)
      return -1;
    cptr += minfo.RegionSize;
    size -= minfo.RegionSize;
  }
  return 0;
}

#define MMAP_DEFAULT(s)             win32mmap(s)
#define MUNMAP_DEFAULT(a, s)        win32munmap((a), (s))
#define DIRECT_MMAP_DEFAULT(s)      win32direct_mmap(s)
#endif /* WIN32 */
#endif /* HAVE_MMAP */

#if HAVE_MREMAP
#ifndef WIN32
#define MREMAP_DEFAULT(addr, osz, nsz, mv) mremap((addr), (osz), (nsz), (mv))
#endif /* WIN32 */
#endif /* HAVE_MREMAP */

/**
 * Define CALL_MORECORE
 */
#if HAVE_MORECORE
    #ifdef MORECORE
        #define CALL_MORECORE(S)    MORECORE(S)
    #else  /* MORECORE */
        #define CALL_MORECORE(S)    MORECORE_DEFAULT(S)
    #endif /* MORECORE */
#else  /* HAVE_MORECORE */
    #define CALL_MORECORE(S)        MFAIL
#endif /* HAVE_MORECORE */

/**
 * Define CALL_MMAP/CALL_MUNMAP/CALL_DIRECT_MMAP
 */
#if HAVE_MMAP
    #define USE_MMAP_BIT            (SIZE_T_ONE)

    #ifdef MMAP
        #define CALL_MMAP(s)        MMAP(s)
    #else /* MMAP */
        #define CALL_MMAP(s)        MMAP_DEFAULT(s)
    #endif /* MMAP */
    #ifdef MUNMAP
        #define CALL_MUNMAP(a, s)   MUNMAP((a), (s))
    #else /* MUNMAP */
        #define CALL_MUNMAP(a, s)   MUNMAP_DEFAULT((a), (s))
    #endif /* MUNMAP */
    #ifdef DIRECT_MMAP
        #define CALL_DIRECT_MMAP(s) DIRECT_MMAP(s)
    #else /* DIRECT_MMAP */
        #define CALL_DIRECT_MMAP(s) DIRECT_MMAP_DEFAULT(s)
    #endif /* DIRECT_MMAP */
#else  /* HAVE_MMAP */
    #define USE_MMAP_BIT            (SIZE_T_ZERO)

    #define MMAP(s)                 MFAIL
    #define MUNMAP(a, s)            (-1)
    #define DIRECT_MMAP(s)          MFAIL
    #define CALL_DIRECT_MMAP(s)     DIRECT_MMAP(s)
    #define CALL_MMAP(s)            MMAP(s)
    #define CALL_MUNMAP(a, s)       MUNMAP((a), (s))
#endif /* HAVE_MMAP */

/**
 * Define CALL_MREMAP
 */
#if HAVE_MMAP && HAVE_MREMAP
    #ifdef MREMAP
        #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP((addr), (osz), (nsz), (mv))
    #else /* MREMAP */
        #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP_DEFAULT((addr), (osz), (nsz), (mv))
    #endif /* MREMAP */
#else  /* HAVE_MMAP && HAVE_MREMAP */
    #define CALL_MREMAP(addr, osz, nsz, mv)     MFAIL
#endif /* HAVE_MMAP && HAVE_MREMAP */

/* mstate bit set if contiguous morecore disabled or failed */
#define USE_NONCONTIGUOUS_BIT (4U)

/* mstate bit set if no expansion allowed */
#define USE_NOEXPAND_BIT (8U)

/* trace allocations if set */
#define USE_TRACE_BIT (16U)

/* segment bit set in create_mspace_with_base */
#define EXTERN_BIT            (8U)


/* --------------------------- Lock preliminaries ------------------------ */

/*
  When locks are defined, there is one global lock, plus
  one per-mspace lock.

  The global lock_ensures that mparams.magic and other unique
  mparams values are initialized only once. It also protects
  sequences of calls to MORECORE.  In many cases sys_alloc requires
  two calls, that should not be interleaved with calls by other
  threads.  This does not protect against direct calls to MORECORE
  by other threads not using this lock, so there is still code to
  cope the best we can on interference.

  Per-mspace locks surround calls to malloc, free, etc.
  By default, locks are simple non-reentrant mutexes.

  Because lock-protected regions generally have bounded times, it is
  OK to use the supplied simple spinlocks. Spinlocks are likely to
  improve performance for lightly contended applications, but worsen
  performance under heavy contention.

  If USE_LOCKS is > 1, the definitions of lock routines here are
  bypassed, in which case you will need to define the type MLOCK_T,
  and at least INITIAL_LOCK, DESTROY_LOCK, ACQUIRE_LOCK, RELEASE_LOCK
  and TRY_LOCK.  You must also declare a
    static MLOCK_T malloc_global_mutex = { initialization values };.

*/

#if !USE_LOCKS
#define USE_LOCK_BIT               (0U)
#define INITIAL_LOCK(l)            (0)
#define DESTROY_LOCK(l)            (0)
#define ACQUIRE_MALLOC_GLOBAL_LOCK()
#define RELEASE_MALLOC_GLOBAL_LOCK()

#else
#if USE_LOCKS > 1
/* -----------------------  User-defined locks ------------------------ */
/* Define your own lock implementation here */
/* #define INITIAL_LOCK(lk)  ... */
/* #define DESTROY_LOCK(lk)  ... */
/* #define ACQUIRE_LOCK(lk)  ... */
/* #define RELEASE_LOCK(lk)  ... */
/* #define TRY_LOCK(lk) ... */
/* static MLOCK_T malloc_global_mutex = ... */

#elif USE_SPIN_LOCKS

/* First, define CAS_LOCK and CLEAR_LOCK on ints */
/* Note CAS_LOCK defined to return 0 on success */

#if defined(__GNUC__)&& (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1))
#define CAS_LOCK(sl)     __sync_lock_test_and_set(sl, 1)
#define CLEAR_LOCK(sl)   __sync_lock_release(sl)

#elif (defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)))
/* Custom spin locks for older gcc on x86 */
static FORCEINLINE int x86_cas_lock(int *sl) {
  int ret;
  int val = 1;
  int cmp = 0;
  __asm__ __volatile__  ("lock; cmpxchgl %1, %2"
                         : "=a" (ret)
                         : "r" (val), "m" (*(sl)), "0"(cmp)
                         : "memory", "cc");
  return ret;
}

static FORCEINLINE void x86_clear_lock(int* sl) {
  assert(*sl != 0);
  int prev = 0;
  int ret;
  __asm__ __volatile__ ("lock; xchgl %0, %1"
                        : "=r" (ret)
                        : "m" (*(sl)), "0"(prev)
                        : "memory");
}

#define CAS_LOCK(sl)     x86_cas_lock(sl)
#define CLEAR_LOCK(sl)   x86_clear_lock(sl)

#else /* Win32 MSC */
#define CAS_LOCK(sl)     interlockedexchange(sl, (LONG)1)
#define CLEAR_LOCK(sl)   interlockedexchange (sl, (LONG)0)

#endif /* ... gcc spins locks ... */

/* How to yield for a spin lock */
#define SPINS_PER_YIELD       63
#if defined(_MSC_VER)
#define SLEEP_EX_DURATION     50 /* delay for yield/sleep */
#define SPIN_LOCK_YIELD  SleepEx(SLEEP_EX_DURATION, FALSE)
#elif defined (__SVR4) && defined (__sun) /* solaris */
#define SPIN_LOCK_YIELD   thr_yield();
#elif !defined(LACKS_SCHED_H)
#define SPIN_LOCK_YIELD   sched_yield();
#else
#define SPIN_LOCK_YIELD
#endif /* ... yield ... */

#if !defined(USE_RECURSIVE_LOCKS) || USE_RECURSIVE_LOCKS == 0
/* Plain spin locks use single word (embedded in malloc_states) */
CLIB_NOSANITIZE_ADDR
static int spin_acquire_lock(int *sl) {
  int spins = 0;
  while (*(volatile int *)sl != 0 || CAS_LOCK(sl)) {
    if ((++spins & SPINS_PER_YIELD) == 0) {
      SPIN_LOCK_YIELD;
    }
  }
  return 0;
}

#define MLOCK_T               int
#define TRY_LOCK(sl)          !CAS_LOCK(sl)
#define RELEASE_LOCK(sl)      CLEAR_LOCK(sl)
#define ACQUIRE_LOCK(sl)      (CAS_LOCK(sl)? spin_acquire_lock(sl) : 0)
#define INITIAL_LOCK(sl)      (*sl = 0)
#define DESTROY_LOCK(sl)      (0)
static MLOCK_T malloc_global_mutex = 0;

#else /* USE_RECURSIVE_LOCKS */
/* types for lock owners */
#ifdef WIN32
#define THREAD_ID_T           DWORD
#define CURRENT_THREAD        GetCurrentThreadId()
#define EQ_OWNER(X,Y)         ((X) == (Y))
#else
/*
  Note: the following assume that pthread_t is a type that can be
  initialized to (casted) zero. If this is not the case, you will need to
  somehow redefine these or not use spin locks.
*/
#define THREAD_ID_T           pthread_t
#define CURRENT_THREAD        pthread_self()
#define EQ_OWNER(X,Y)         pthread_equal(X, Y)
#endif

struct malloc_recursive_lock {
  int sl;
  unsigned int c;
  THREAD_ID_T threadid;
};

#define MLOCK_T  struct malloc_recursive_lock
static MLOCK_T malloc_global_mutex = { 0, 0, (THREAD_ID_T)0};

static FORCEINLINE void recursive_release_lock(MLOCK_T *lk) {
  assert(lk->sl != 0);
  if (--lk->c == 0) {
    CLEAR_LOCK(&lk->sl);
  }
}

static FORCEINLINE int recursive_acquire_lock(MLOCK_T *lk) {
  THREAD_ID_T mythreadid = CURRENT_THREAD;
  int spins = 0;
  for (;;) {
    if (*((volatile int *)(&lk->sl)) == 0) {
      if (!CAS_LOCK(&lk->sl)) {
        lk->threadid = mythreadid;
        lk->c = 1;
        return 0;
      }
    }
    else if (EQ_OWNER(lk->threadid, mythreadid)) {
      ++lk->c;
      return 0;
    }
    if ((++spins & SPINS_PER_YIELD) == 0) {
      SPIN_LOCK_YIELD;
    }
  }
}

static FORCEINLINE int recursive_try_lock(MLOCK_T *lk) {
  THREAD_ID_T mythreadid = CURRENT_THREAD;
  if (*((volatile int *)(&lk->sl)) == 0) {
    if (!CAS_LOCK(&lk->sl)) {
      lk->threadid = mythreadid;
      lk->c = 1;
      return 1;
    }
  }
  else if (EQ_OWNER(lk->threadid, mythreadid)) {
    ++lk->c;
    return 1;
  }
  return 0;
}

#define RELEASE_LOCK(lk)      recursive_release_lock(lk)
#define TRY_LOCK(lk)          recursive_try_lock(lk)
#define ACQUIRE_LOCK(lk)      recursive_acquire_lock(lk)
#define INITIAL_LOCK(lk)      ((lk)->threadid = (THREAD_ID_T)0, (lk)->sl = 0, (lk)->c = 0)
#define DESTROY_LOCK(lk)      (0)
#endif /* USE_RECURSIVE_LOCKS */

#elif defined(WIN32) /* Win32 critical sections */
#define MLOCK_T               CRITICAL_SECTION
#define ACQUIRE_LOCK(lk)      (EnterCriticalSection(lk), 0)
#define RELEASE_LOCK(lk)      LeaveCriticalSection(lk)
#define TRY_LOCK(lk)          TryEnterCriticalSection(lk)
#define INITIAL_LOCK(lk)      (!InitializeCriticalSectionAndSpinCount((lk), 0x80000000|4000))
#define DESTROY_LOCK(lk)      (DeleteCriticalSection(lk), 0)
#define NEED_GLOBAL_LOCK_INIT

static MLOCK_T malloc_global_mutex;
static volatile LONG malloc_global_mutex_status;

/* Use spin loop to initialize global lock */
static void init_malloc_global_mutex() {
  for (;;) {
    long stat = malloc_global_mutex_status;
    if (stat > 0)
      return;
    /* transition to < 0 while initializing, then to > 0) */
    if (stat == 0 &&
        interlockedcompareexchange(&malloc_global_mutex_status, (LONG)-1, (LONG)0) == 0) {
      InitializeCriticalSection(&malloc_global_mutex);
      interlockedexchange(&malloc_global_mutex_status, (LONG)1);
      return;
    }
    SleepEx(0, FALSE);
  }
}

#else /* pthreads-based locks */
#define MLOCK_T               pthread_mutex_t
#define ACQUIRE_LOCK(lk)      pthread_mutex_lock(lk)
#define RELEASE_LOCK(lk)      pthread_mutex_unlock(lk)
#define TRY_LOCK(lk)          (!pthread_mutex_trylock(lk))
#define INITIAL_LOCK(lk)      pthread_init_lock(lk)
#define DESTROY_LOCK(lk)      pthread_mutex_destroy(lk)

#if defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0 && defined(linux) && !defined(PTHREAD_MUTEX_RECURSIVE)
/* Cope with old-style linux recursive lock initialization by adding */
/* skipped internal declaration from pthread.h */
extern int pthread_mutexattr_setkind_np __P ((pthread_mutexattr_t *__attr,
                                              int __kind));
#define PTHREAD_MUTEX_RECURSIVE PTHREAD_MUTEX_RECURSIVE_NP
#define pthread_mutexattr_settype(x,y) pthread_mutexattr_setkind_np(x,y)
#endif /* USE_RECURSIVE_LOCKS ... */

static MLOCK_T malloc_global_mutex = PTHREAD_MUTEX_INITIALIZER;

static int pthread_init_lock (MLOCK_T *lk) {
  pthread_mutexattr_t attr;
  if (pthread_mutexattr_init(&attr)) return 1;
#if defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0
  if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) return 1;
#endif
  if (pthread_mutex_init(lk, &attr)) return 1;
  if (pthread_mutexattr_destroy(&attr)) return 1;
  return 0;
}

#endif /* ... lock types ... */

/* Common code for all lock types */
#define USE_LOCK_BIT               (2U)

#ifndef ACQUIRE_MALLOC_GLOBAL_LOCK
#define ACQUIRE_MALLOC_GLOBAL_LOCK()  ACQUIRE_LOCK(&malloc_global_mutex);
#endif

#ifndef RELEASE_MALLOC_GLOBAL_LOCK
#define RELEASE_MALLOC_GLOBAL_LOCK()  RELEASE_LOCK(&malloc_global_mutex);
#endif

#endif /* USE_LOCKS */

/* -----------------------  Chunk representations ------------------------ */

/*
  (The following includes lightly edited explanations by Colin Plumb.)

  The malloc_chunk declaration below is misleading (but accurate and
  necessary).  It declares a "view" into memory allowing access to
  necessary fields at known offsets from a given base.

  Chunks of memory are maintained using a `boundary tag' method as
  originally described by Knuth.  (See the paper by Paul Wilson
  ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a survey of such
  techniques.)  Sizes of free chunks are stored both in the front of
  each chunk and at the end.  This makes consolidating fragmented
  chunks into bigger chunks fast.  The head fields also hold bits
  representing whether chunks are free or in use.

  Here are some pictures to make it clearer.  They are "exploded" to
  show that the state of a chunk can be thought of as extending from
  the high 31 bits of the head field of its header through the
  prev_foot and PINUSE_BIT bit of the following chunk header.

  A chunk that's in use looks like:

   chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           | Size of previous chunk (if P = 0)                             |
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
         | Size of this chunk                                         1| +-+
   mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                                                               |
         +-                                                             -+
         |                                                               |
         +-                                                             -+
         |                                                               :
         +-      size - sizeof(size_t) available payload bytes          -+
         :                                                               |
 chunk-> +-                                                             -+
         |                                                               |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1|
       | Size of next chunk (may or may not be in use)               | +-+
 mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

    And if it's free, it looks like this:

   chunk-> +-                                                             -+
           | User payload (must be in use, or we would have merged!)       |
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
         | Size of this chunk                                         0| +-+
   mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         | Next pointer                                                  |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         | Prev pointer                                                  |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         |                                                               :
         +-      size - sizeof(struct chunk) unused bytes               -+
         :                                                               |
 chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         | Size of this chunk                                            |
         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0|
       | Size of next chunk (must be in use, or we would have merged)| +-+
 mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               :
       +- User payload                                                -+
       :                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                                                                     |0|
                                                                     +-+
  Note that since we always merge adjacent free chunks, the chunks
  adjacent to a free chunk must be in use.

  Given a pointer to a chunk (which can be derived trivially from the
  payload pointer) we can, in O(1) time, find out whether the adjacent
  chunks are free, and if so, unlink them from the lists that they
  are on and merge them with the current chunk.

  Chunks always begin on even word boundaries, so the mem portion
  (which is returned to the user) is also on an even word boundary, and
  thus at least double-word aligned.

  The P (PINUSE_BIT) bit, stored in the unused low-order bit of the
  chunk size (which is always a multiple of two words), is an in-use
  bit for the *previous* chunk.  If that bit is *clear*, then the
  word before the current chunk size contains the previous chunk
  size, and can be used to find the front of the previous chunk.
  The very first chunk allocated always has this bit set, preventing
  access to non-existent (or non-owned) memory. If pinuse is set for
  any given chunk, then you CANNOT determine the size of the
  previous chunk, and might even get a memory addressing fault when
  trying to do so.

  The C (CINUSE_BIT) bit, stored in the unused second-lowest bit of
  the chunk size redundantly records whether the current chunk is
  inuse (unless the chunk is mmapped). This redundancy enables usage
  checks within free and realloc, and reduces indirection when freeing
  and consolidating chunks.

  Each freshly allocated chunk must have both cinuse and pinuse set.
  That is, each allocated chunk borders either a previously allocated
  and still in-use chunk, or the base of its memory arena. This is
  ensured by making all allocations from the `lowest' part of any
  found chunk.  Further, no free chunk physically borders another one,
  so each free chunk is known to be preceded and followed by either
  inuse chunks or the ends of memory.

  Note that the `foot' of the current chunk is actually represented
  as the prev_foot of the NEXT chunk. This makes it easier to
  deal with alignments etc but can be very confusing when trying
  to extend or adapt this code.

  The exceptions to all this are

     1. The special chunk `top' is the top-most available chunk (i.e.,
        the one bordering the end of available memory). It is treated
        specially.  Top is never included in any bin, is used only if
        no other chunk is available, and is released back to the
        system if it is very large (see M_TRIM_THRESHOLD).  In effect,
        the top chunk is treated as larger (and thus less well
        fitting) than any other available chunk.  The top chunk
        doesn't update its trailing size field since there is no next
        contiguous chunk that would have to index off it. However,
        space is still allocated for it (TOP_FOOT_SIZE) to enable
        separation or merging when space is extended.

     3. Chunks allocated via mmap, have both cinuse and pinuse bits
        cleared in their head fields.  Because they are allocated
        one-by-one, each must carry its own prev_foot field, which is
        also used to hold the offset this chunk has within its mmapped
        region, which is needed to preserve alignment. Each mmapped
        chunk is trailed by the first two fields of a fake next-chunk
        for sake of usage checks.

*/

struct malloc_chunk {
  size_t               prev_foot;  /* Size of previous chunk (if free).  */
  size_t               head;       /* Size and inuse bits. */
  struct malloc_chunk* fd;         /* double links -- used only if free. */
  struct malloc_chunk* bk;
};

typedef struct malloc_chunk  mchunk;
typedef struct malloc_chunk* mchunkptr;
typedef struct malloc_chunk* sbinptr;  /* The type of bins of chunks */
typedef unsigned int bindex_t;         /* Described below */
typedef unsigned int binmap_t;         /* Described below */
typedef unsigned int flag_t;           /* The type of various bit flag sets */

/* ------------------- Chunks sizes and alignments ----------------------- */

#define MCHUNK_SIZE         (sizeof(mchunk))

#if FOOTERS
#define CHUNK_OVERHEAD      (TWO_SIZE_T_SIZES)
#else /* FOOTERS */
#define CHUNK_OVERHEAD      (SIZE_T_SIZE)
#endif /* FOOTERS */

/* MMapped chunks need a second word of overhead ... */
#define MMAP_CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
/* ... and additional padding for fake next-chunk at foot */
#define MMAP_FOOT_PAD       (FOUR_SIZE_T_SIZES)

/* The smallest size we can malloc is an aligned minimal chunk */
#define MIN_CHUNK_SIZE\
  ((MCHUNK_SIZE + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)

/* conversion from malloc headers to user pointers, and back */
#define chunk2mem(p)        ((void*)((char*)(p)       + TWO_SIZE_T_SIZES))
#define mem2chunk(mem)      ((mchunkptr)((char*)(mem) - TWO_SIZE_T_SIZES))
/* chunk associated with aligned address A */
#define align_as_chunk(A)   (mchunkptr)((A) + align_offset(chunk2mem(A)))

/* Bounds on request (not chunk) sizes. */
#define MAX_REQUEST         ((-MIN_CHUNK_SIZE) << 2)
#define MIN_REQUEST         (MIN_CHUNK_SIZE - CHUNK_OVERHEAD - SIZE_T_ONE)

/* pad request bytes into a usable size */
#define pad_request(req) \
   (((req) + CHUNK_OVERHEAD + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)

/* pad request, checking for minimum (but not maximum) */
#define request2size(req) \
  (((req) < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(req))


/* ------------------ Operations on head and foot fields ----------------- */

/*
  The head field of a chunk is or'ed with PINUSE_BIT when previous
  adjacent chunk in use, and or'ed with CINUSE_BIT if this chunk is in
  use, unless mmapped, in which case both bits are cleared.

  FLAG4_BIT is not used by this malloc, but might be useful in extensions.
*/

#define PINUSE_BIT          (SIZE_T_ONE)
#define CINUSE_BIT          (SIZE_T_TWO)
#define FLAG4_BIT           (SIZE_T_FOUR)
#define INUSE_BITS          (PINUSE_BIT|CINUSE_BIT)
#define FLAG_BITS           (PINUSE_BIT|CINUSE_BIT|FLAG4_BIT)

/* Head value for fenceposts */
#define FENCEPOST_HEAD      (INUSE_BITS|SIZE_T_SIZE)

/* extraction of fields from head words */
#define cinuse(p)           ((p)->head & CINUSE_BIT)
#define pinuse(p)           ((p)->head & PINUSE_BIT)
#define flag4inuse(p)       ((p)->head & FLAG4_BIT)
#define is_inuse(p)         (((p)->head & INUSE_BITS) != PINUSE_BIT)
#define is_mmapped(p)       (((p)->head & INUSE_BITS) == 0)

#define chunksize(p)        ((p)->head & ~(FLAG_BITS))

#define clear_pinuse(p)     ((p)->head &= ~PINUSE_BIT)
#define set_flag4(p)        ((p)->head |= FLAG4_BIT)
#define clear_flag4(p)      ((p)->head &= ~FLAG4_BIT)

/* Treat space at ptr +/- offset as a chunk */
#define chunk_plus_offset(p, s)  ((mchunkptr)(((char*)(p)) + (s)))
#define chunk_minus_offset(p, s) ((mchunkptr)(((char*)(p)) - (s)))

/* Ptr to next or previous physical malloc_chunk. */
#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->head & ~FLAG_BITS)))
#define prev_chunk(p) ((mchunkptr)( ((char*)(p)) - ((p)->prev_foot) ))

/* extract next chunk's pinuse bit */
#define next_pinuse(p)  ((next_chunk(p)->head) & PINUSE_BIT)

/* Get/set size at footer */
#define get_foot(p, s)  (((mchunkptr)((char*)(p) + (s)))->prev_foot)
#define set_foot(p, s)  (((mchunkptr)((char*)(p) + (s)))->prev_foot = (s))

/* Set size, pinuse bit, and foot */
#define set_size_and_pinuse_of_free_chunk(p, s)\
  ((p)->head = (s|PINUSE_BIT), set_foot(p, s))

/* Set size, pinuse bit, foot, and clear next pinuse */
#define set_free_with_pinuse(p, s, n)\
  (clear_pinuse(n), set_size_and_pinuse_of_free_chunk(p, s))

/* Get the internal overhead associated with chunk p */
#define overhead_for(p)\
 (is_mmapped(p)? MMAP_CHUNK_OVERHEAD : CHUNK_OVERHEAD)

/* Return true if malloced space is not necessarily cleared */
#if MMAP_CLEARS
#define calloc_must_clear(p) (!is_mmapped(p))
#else /* MMAP_CLEARS */
#define calloc_must_clear(p) (1)
#endif /* MMAP_CLEARS */

/* ---------------------- Overlaid data structures ----------------------- */

/*
  When chunks are not in use, they are treated as nodes of either
  lists or trees.

  "Small"  chunks are stored in circular doubly-linked lists, and look
  like this:

    chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Size of previous chunk                            |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    `head:' |             Size of chunk, in bytes                         |P|
      mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Forward pointer to next chunk in list             |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Back pointer to previous chunk in list            |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Unused space (may be 0 bytes long)                .
            .                                                               .
            .                                                               |
nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    `foot:' |             Size of chunk, in bytes                           |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  Larger chunks are kept in a form of bitwise digital trees (aka
  tries) keyed on chunksizes.  Because malloc_tree_chunks are only for
  free chunks greater than 256 bytes, their size doesn't impose any
  constraints on user chunk sizes.  Each node looks like:

    chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Size of previous chunk                            |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    `head:' |             Size of chunk, in bytes                         |P|
      mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Forward pointer to next chunk of same size        |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Back pointer to previous chunk of same size       |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Pointer to left child (child[0])                  |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Pointer to right child (child[1])                 |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Pointer to parent                                 |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             bin index of this chunk                           |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |             Unused space                                      .
            .                                                               |
nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    `foot:' |             Size of chunk, in bytes                           |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  Each tree holding treenodes is a tree of unique chunk sizes.  Chunks
  of the same size are arranged in a circularly-linked list, with only
  the oldest chunk (the next to be used, in our FIFO ordering)
  actually in the tree.  (Tree members are distinguished by a non-null
  parent pointer.)  If a chunk with the same size an an existing node
  is inserted, it is linked off the existing node using pointers that
  work in the same way as fd/bk pointers of small chunks.

  Each tree contains a power of 2 sized range of chunk sizes (the
  smallest is 0x100 <= x < 0x180), which is is divided in half at each
  tree level, with the chunks in the smaller half of the range (0x100
  <= x < 0x140 for the top nose) in the left subtree and the larger
  half (0x140 <= x < 0x180) in the right subtree.  This is, of course,
  done by inspecting individual bits.

  Using these rules, each node's left subtree contains all smaller
  sizes than its right subtree.  However, the node at the root of each
  subtree has no particular ordering relationship to either.  (The
  dividing line between the subtree sizes is based on trie relation.)
  If we remove the last chunk of a given size from the interior of the
  tree, we need to replace it with a leaf node.  The tree ordering
  rules permit a node to be replaced by any leaf below it.

  The smallest chunk in a tree (a common operation in a best-fit
  allocator) can be found by walking a path to the leftmost leaf in
  the tree.  Unlike a usual binary tree, where we follow left child
  pointers until we reach a null, here we follow the right child
  pointer any time the left one is null, until we reach a leaf with
  both child pointers null. The smallest chunk in the tree will be
  somewhere along that path.

  The worst case number of steps to add, find, or remove a node is
  bounded by the number of bits differentiating chunks within
  bins. Under current bin calculations, this ranges from 6 up to 21
  (for 32 bit sizes) or up to 53 (for 64 bit sizes). The typical case
  is of course much better.
*/

struct malloc_tree_chunk {
  /* The first four fields must be compatible with malloc_chunk */
  size_t                    prev_foot;
  size_t                    head;
  struct malloc_tree_chunk* fd;
  struct malloc_tree_chunk* bk;

  struct malloc_tree_chunk* child[2];
  struct malloc_tree_chunk* parent;
  bindex_t                  index;
};

typedef struct malloc_tree_chunk  tchunk;
typedef struct malloc_tree_chunk* tchunkptr;
typedef struct malloc_tree_chunk* tbinptr; /* The type of bins of trees */

/* A little helper macro for trees */
#define leftmost_child(t) ((t)->child[0] != 0? (t)->child[0] : (t)->child[1])

/* ----------------------------- Segments -------------------------------- */

/*
  Each malloc space may include non-contiguous segments, held in a
  list headed by an embedded malloc_segment record representing the
  top-most space. Segments also include flags holding properties of
  the space. Large chunks that are directly allocated by mmap are not
  included in this list. They are instead independently created and
  destroyed without otherwise keeping track of them.

  Segment management mainly comes into play for spaces allocated by
  MMAP.  Any call to MMAP might or might not return memory that is
  adjacent to an existing segment.  MORECORE normally contiguously
  extends the current space, so this space is almost always adjacent,
  which is simpler and faster to deal with. (This is why MORECORE is
  used preferentially to MMAP when both are available -- see
  sys_alloc.)  When allocating using MMAP, we don't use any of the
  hinting mechanisms (inconsistently) supported in various
  implementations of unix mmap, or distinguish reserving from
  committing memory. Instead, we just ask for space, and exploit
  contiguity when we get it.  It is probably possible to do
  better than this on some systems, but no general scheme seems
  to be significantly better.

  Management entails a simpler variant of the consolidation scheme
  used for chunks to reduce fragmentation -- new adjacent memory is
  normally prepended or appended to an existing segment. However,
  there are limitations compared to chunk consolidation that mostly
  reflect the fact that segment processing is relatively infrequent
  (occurring only when getting memory from system) and that we
  don't expect to have huge numbers of segments:

  * Segments are not indexed, so traversal requires linear scans.  (It
    would be possible to index these, but is not worth the extra
    overhead and complexity for most programs on most platforms.)
  * New segments are only appended to old ones when holding top-most
    memory; if they cannot be prepended to others, they are held in
    different segments.

  Except for the top-most segment of an mstate, each segment record
  is kept at the tail of its segment. Segments are added by pushing
  segment records onto the list headed by &mstate.seg for the
  containing mstate.

  Segment flags control allocation/merge/deallocation policies:
  * If EXTERN_BIT set, then we did not allocate this segment,
    and so should not try to deallocate or merge with others.
    (This currently holds only for the initial segment passed
    into create_mspace_with_base.)
  * If USE_MMAP_BIT set, the segment may be merged with
    other surrounding mmapped segments and trimmed/de-allocated
    using munmap.
  * If neither bit is set, then the segment was obtained using
    MORECORE so can be merged with surrounding MORECORE'd segments
    and deallocated/trimmed using MORECORE with negative arguments.
*/

struct malloc_segment {
  char*        base;             /* base address */
  size_t       size;             /* allocated size */
  struct malloc_segment* next;   /* ptr to next segment */
  flag_t       sflags;           /* mmap and extern flag */
};

#define is_mmapped_segment(S)  ((S)->sflags & USE_MMAP_BIT)
#define is_extern_segment(S)   ((S)->sflags & EXTERN_BIT)

typedef struct malloc_segment  msegment;
typedef struct malloc_segment* msegmentptr;

/* ---------------------------- malloc_state ----------------------------- */

/*
   A malloc_state holds all of the bookkeeping for a space.
   The main fields are:

  Top
    The topmost chunk of the currently active segment. Its size is
    cached in topsize.  The actual size of topmost space is
    topsize+TOP_FOOT_SIZE, which includes space reserved for adding
    fenceposts and segment records if necessary when getting more
    space from the system.  The size at which to autotrim top is
    cached from mparams in trim_check, except that it is disabled if
    an autotrim fails.

  Designated victim (dv)
    This is the preferred chunk for servicing small requests that
    don't have exact fits.  It is normally the chunk split off most
    recently to service another small request.  Its size is cached in
    dvsize. The link fields of this chunk are not maintained since it
    is not kept in a bin.

  SmallBins
    An array of bin headers for free chunks.  These bins hold chunks
    with sizes less than MIN_LARGE_SIZE bytes. Each bin contains
    chunks of all the same size, spaced 8 bytes apart.  To simplify
    use in double-linked lists, each bin header acts as a malloc_chunk
    pointing to the real first node, if it exists (else pointing to
    itself).  This avoids special-casing for headers.  But to avoid
    waste, we allocate only the fd/bk pointers of bins, and then use
    repositioning tricks to treat these as the fields of a chunk.

  TreeBins
    Treebins are pointers to the roots of trees holding a range of
    sizes. There are 2 equally spaced treebins for each power of two
    from TREE_SHIFT to TREE_SHIFT+16. The last bin holds anything
    larger.

  Bin maps
    There is one bit map for small bins ("smallmap") and one for
    treebins ("treemap).  Each bin sets its bit when non-empty, and
    clears the bit when empty.  Bit operations are then used to avoid
    bin-by-bin searching -- nearly all "search" is done without ever
    looking at bins that won't be selected.  The bit maps
    conservatively use 32 bits per map word, even if on 64bit system.
    For a good description of some of the bit-based techniques used
    here, see Henry S. Warren Jr's book "Hacker's Delight" (and
    supplement at http://hackersdelight.org/). Many of these are
    intended to reduce the branchiness of paths through malloc etc, as
    well as to reduce the number of memory locations read or written.

  Segments
    A list of segments headed by an embedded malloc_segment record
    representing the initial space.

  Address check support
    The least_addr field is the least address ever obtained from
    MORECORE or MMAP. Attempted frees and reallocs of any address less
    than this are trapped (unless INSECURE is defined).

  Magic tag
    A cross-check field that should always hold same value as mparams.magic.

  Max allowed footprint
    The maximum allowed bytes to allocate from system (zero means no limit)

  Flags
    Bits recording whether to use MMAP, locks, or contiguous MORECORE

  Statistics
    Each space keeps track of current and maximum system memory
    obtained via MORECORE or MMAP.

  Trim support
    Fields holding the amount of unused topmost memory that should trigger
    trimming, and a counter to force periodic scanning to release unused
    non-topmost segments.

  Locking
    If USE_LOCKS is defined, the "mutex" lock is acquired and released
    around every public call using this mspace.

  Extension support
    A void* pointer and a size_t field that can be used to help implement
    extensions to this malloc.
*/

/* Bin types, widths and sizes */
#define NSMALLBINS        (32U)
#define NTREEBINS         (32U)
#define SMALLBIN_SHIFT    (3U)
#define SMALLBIN_WIDTH    (SIZE_T_ONE << SMALLBIN_SHIFT)
#define TREEBIN_SHIFT     (8U)
#define MIN_LARGE_SIZE    (SIZE_T_ONE << TREEBIN_SHIFT)
#define MAX_SMALL_SIZE    (MIN_LARGE_SIZE - SIZE_T_ONE)
#define MAX_SMALL_REQUEST (MAX_SMALL_SIZE - CHUNK_ALIGN_MASK - CHUNK_OVERHEAD)

struct malloc_state {
  binmap_t   smallmap;
  binmap_t   treemap;
  size_t     dvsize;
  size_t     topsize;
  char*      least_addr;
  mchunkptr  dv;
  mchunkptr  top;
  size_t     trim_check;
  size_t     release_checks;
  size_t     magic;
  mchunkptr  smallbins[(NSMALLBINS+1)*2];
  tbinptr    treebins[NTREEBINS];
  size_t     footprint;
  size_t     max_footprint;
  size_t     footprint_limit; /* zero means no limit */
  flag_t     mflags;
#if USE_LOCKS
  MLOCK_T    mutex;     /* locate lock among fields that rarely change */
#endif /* USE_LOCKS */
  msegment   seg;
  void*      extp;      /* Unused but available for extensions */
  size_t     exts;
};

typedef struct malloc_state*    mstate;

/* ------------- Global malloc_state and malloc_params ------------------- */

/*
  malloc_params holds global properties, including those that can be
  dynamically set using mallopt. There is a single instance, mparams,
  initialized in init_mparams. Note that the non-zeroness of "magic"
  also serves as an initialization flag.
*/

struct malloc_params {
  size_t magic;
  size_t page_size;
  size_t granularity;
  size_t mmap_threshold;
  size_t trim_threshold;
  flag_t default_mflags;
};

static struct malloc_params mparams;

/* Ensure mparams initialized */
#define ensure_initialization() (void)(mparams.magic != 0 || init_mparams())

#if !ONLY_MSPACES

/* The global malloc_state used for all non-"mspace" calls */
static struct malloc_state _gm_;
#define gm                 (&_gm_)
#define is_global(M)       ((M) == &_gm_)

#endif /* !ONLY_MSPACES */

#define is_initialized(M)  ((M)->top != 0)

/* -------------------------- system alloc setup ------------------------- */

/* Operations on mflags */

#define use_lock(M)           ((M)->mflags &   USE_LOCK_BIT)
#define enable_lock(M)        ((M)->mflags |=  USE_LOCK_BIT)
#if USE_LOCKS
#define disable_lock(M)       ((M)->mflags &= ~USE_LOCK_BIT)
#else
#define disable_lock(M)
#endif

#define use_mmap(M)           ((M)->mflags &   USE_MMAP_BIT)
#define enable_mmap(M)        ((M)->mflags |=  USE_MMAP_BIT)
#if HAVE_MMAP
#define disable_mmap(M)       ((M)->mflags &= ~USE_MMAP_BIT)
#else
#define disable_mmap(M)
#endif

#define use_noncontiguous(M)  ((M)->mflags &   USE_NONCONTIGUOUS_BIT)
#define disable_contiguous(M) ((M)->mflags |=  USE_NONCONTIGUOUS_BIT)
#define use_noexpand(M) ((M)->mflags & USE_NOEXPAND_BIT)
#define disable_expand(M) ((M)->mflags |= USE_NOEXPAND_BIT)
#define use_trace(M) ((M)->mflags & USE_TRACE_BIT)
#define enable_trace(M) ((M)->mflags |= USE_TRACE_BIT)
#define disable_trace(M) ((M)->mflags &= ~USE_TRACE_BIT)

#define set_lock(M,L)\
 ((M)->mflags = (L)?\
  ((M)->mflags | USE_LOCK_BIT) :\
  ((M)->mflags & ~USE_LOCK_BIT))

/* page-align a size */
#define page_align(S)\
 (((S) + (mparams.page_size - SIZE_T_ONE)) & ~(mparams.page_size - SIZE_T_ONE))

/* granularity-align a size */
#define granularity_align(S)\
  (((S) + (mparams.granularity - SIZE_T_ONE))\
   & ~(mparams.granularity - SIZE_T_ONE))


/* For mmap, use granularity alignment on windows, else page-align */
#ifdef WIN32
#define mmap_align(S) granularity_align(S)
#else
#define mmap_align(S) page_align(S)
#endif

/* For sys_alloc, enough padding to ensure can malloc request on success */
#define SYS_ALLOC_PADDING (TOP_FOOT_SIZE + MALLOC_ALIGNMENT)

#define is_page_aligned(S)\
   (((size_t)(S) & (mparams.page_size - SIZE_T_ONE)) == 0)
#define is_granularity_aligned(S)\
   (((size_t)(S) & (mparams.granularity - SIZE_T_ONE)) == 0)

/*  True if segment S holds address A */
#define segment_holds(S, A)\
  ((char*)(A) >= S->base && (char*)(A) < S->base + S->size)

/* Return segment holding given address */
CLIB_NOSANITIZE_ADDR
static msegmentptr segment_holding(mstate m, char* addr) {
  msegmentptr sp = &m->seg;
  for (;;) {
    if (addr >= sp->base && addr < sp->base + sp->size)
      return sp;
    if ((sp = sp->next) == 0)
      return 0;
  }
}

/* Return true if segment contains a segment link */
CLIB_NOSANITIZE_ADDR
static int has_segment_link(mstate m, msegmentptr ss) {
  msegmentptr sp = &m->seg;
  for (;;) {
    if ((char*)sp >= ss->base && (char*)sp < ss->base + ss->size)
      return 1;
    if ((sp = sp->next) == 0)
      return 0;
  }
}

#ifndef MORECORE_CANNOT_TRIM
#define should_trim(M,s)  ((s) > (M)->trim_check)
#else  /* MORECORE_CANNOT_TRIM */
#define should_trim(M,s)  (0)
#endif /* MORECORE_CANNOT_TRIM */

/*
  TOP_FOOT_SIZE is padding at the end of a segment, including space
  that may be needed to place segment records and fenceposts when new
  noncontiguous segments are added.
*/
#define TOP_FOOT_SIZE\
  (align_offset(chunk2mem(0))+pad_request(sizeof(struct malloc_segment))+MIN_CHUNK_SIZE)


/* -------------------------------  Hooks -------------------------------- */

/*
  PREACTION should be defined to return 0 on success, and nonzero on
  failure. If you are not using locking, you can redefine these to do
  anything you like.
*/

#if USE_LOCKS
#define PREACTION(M)  ((use_lock(M))? ACQUIRE_LOCK(&(M)->mutex) : 0)
#define POSTACTION(M) { if (use_lock(M)) RELEASE_LOCK(&(M)->mutex); }
#else /* USE_LOCKS */

#ifndef PREACTION
#define PREACTION(M) (0)
#endif  /* PREACTION */

#ifndef POSTACTION
#define POSTACTION(M)
#endif  /* POSTACTION */

#endif /* USE_LOCKS */

/*
  CORRUPTION_ERROR_ACTION is triggered upon detected bad addresses.
  USAGE_ERROR_ACTION is triggered on detected bad frees and
  reallocs. The argument p is an address that might have triggered the
  fault. It is ignored by the two predefined actions, but might be
  useful in custom actions that try to help diagnose errors.
*/

#if PROCEED_ON_ERROR

/* A count of the number of corruption errors causing resets */
int malloc_corruption_error_count;

/* default corruption action */
static void reset_on_error(mstate m);

#define CORRUPTION_ERROR_ACTION(m)  reset_on_error(m)
#define USAGE_ERROR_ACTION(m, p)

#else /* PROCEED_ON_ERROR */

#ifndef CORRUPTION_ERROR_ACTION
#define CORRUPTION_ERROR_ACTION(m) DLM_ABORT
#endif /* CORRUPTION_ERROR_ACTION */

#ifndef USAGE_ERROR_ACTION
#define USAGE_ERROR_ACTION(m,p) DLM_ABORT
#endif /* USAGE_ERROR_ACTION */

#endif /* PROCEED_ON_ERROR */


/* -------------------------- Debugging setup ---------------------------- */

#if ! DEBUG

#define check_free_chunk(M,P)
#define check_inuse_chunk(M,P)
#define check_malloced_chunk(M,P,N)
#define check_mmapped_chunk(M,P)
#define check_malloc_state(M)
#define check_top_chunk(M,P)

#else /* DEBUG */
#define check_free_chunk(M,P)       do_check_free_chunk(M,P)
#define check_inuse_chunk(M,P)      do_check_inuse_chunk(M,P)
#define check_top_chunk(M,P)        do_check_top_chunk(M,P)
#define check_malloced_chunk(M,P,N) do_check_malloced_chunk(M,P,N)
#define check_mmapped_chunk(M,P)    do_check_mmapped_chunk(M,P)
#define check_malloc_state(M)       do_check_malloc_state(M)

static void   do_check_any_chunk(mstate m, mchunkptr p);
static void   do_check_top_chunk(mstate m, mchunkptr p);
static void   do_check_mmapped_chunk(mstate m, mchunkptr p);
static void   do_check_inuse_chunk(mstate m, mchunkptr p);
static void   do_check_free_chunk(mstate m, mchunkptr p);
static void   do_check_malloced_chunk(mstate m, void* mem, size_t s);
static void   do_check_tree(mstate m, tchunkptr t);
static void   do_check_treebin(mstate m, bindex_t i);
static void   do_check_smallbin(mstate m, bindex_t i);
static void   do_check_malloc_state(mstate m);
static int    bin_find(mstate m, mchunkptr x);
static size_t traverse_and_check(mstate m);
#endif /* DEBUG */

/* ---------------------------- Indexing Bins ---------------------------- */

#define is_small(s)         (((s) >> SMALLBIN_SHIFT) < NSMALLBINS)
#define small_index(s)      (bindex_t)((s)  >> SMALLBIN_SHIFT)
#define small_index2size(i) ((i)  << SMALLBIN_SHIFT)
#define MIN_SMALL_INDEX     (small_index(MIN_CHUNK_SIZE))

/* addressing by index. See above about smallbin repositioning */
#define smallbin_at(M, i)   ((sbinptr)((char*)&((M)->smallbins[(i)<<1])))
#define treebin_at(M,i)     (&((M)->treebins[i]))

/* assign tree index for size S to variable I. Use x86 asm if possible  */
#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
#define compute_tree_index(S, I)\
{\
  unsigned int X = S >> TREEBIN_SHIFT;\
  if (X == 0)\
    I = 0;\
  else if (X > 0xFFFF)\
    I = NTREEBINS-1;\
  else {\
    unsigned int K = (unsigned) sizeof(X)*__CHAR_BIT__ - 1 - (unsigned) __builtin_clz(X); \
    I =  (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
  }\
}

#elif defined (__INTEL_COMPILER)
#define compute_tree_index(S, I)\
{\
  size_t X = S >> TREEBIN_SHIFT;\
  if (X == 0)\
    I = 0;\
  else if (X > 0xFFFF)\
    I = NTREEBINS-1;\
  else {\
    unsigned int K = _bit_scan_reverse (X); \
    I =  (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
  }\
}

#elif defined(_MSC_VER) && _MSC_VER>=1300
#define compute_tree_index(S, I)\
{\
  size_t X = S >> TREEBIN_SHIFT;\
  if (X == 0)\
    I = 0;\
  else if (X > 0xFFFF)\
    I = NTREEBINS-1;\
  else {\
    unsigned int K;\
    _BitScanReverse((DWORD *) &K, (DWORD) X);\
    I =  (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
  }\
}

#else /* GNUC */
#define compute_tree_index(S, I)\
{\
  size_t X = S >> TREEBIN_SHIFT;\
  if (X == 0)\
    I = 0;\
  else if (X > 0xFFFF)\
    I = NTREEBINS-1;\
  else {\
    unsigned int Y = (unsigned int)X;\
    unsigned int N = ((Y - 0x100) >> 16) & 8;\
    unsigned int K = (((Y <<= N) - 0x1000) >> 16) & 4;\
    N += K;\
    N += K = (((Y <<= K) - 0x4000) >> 16) & 2;\
    K = 14 - N + ((Y <<= K) >> 15);\
    I = (K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1));\
  }\
}
#endif /* GNUC */

/* Bit representing maximum resolved size in a treebin at i */
#define bit_for_tree_index(i) \
   (i == NTREEBINS-1)? (SIZE_T_BITSIZE-1) : (((i) >> 1) + TREEBIN_SHIFT - 2)

/* Shift placing maximum resolved bit in a treebin at i as sign bit */
#define leftshift_for_tree_index(i) \
   ((i == NTREEBINS-1)? 0 : \
    ((SIZE_T_BITSIZE-SIZE_T_ONE) - (((i) >> 1) + TREEBIN_SHIFT - 2)))

/* The size of the smallest chunk held in bin with index i */
#define minsize_for_tree_index(i) \
   ((SIZE_T_ONE << (((i) >> 1) + TREEBIN_SHIFT)) |  \
   (((size_t)((i) & SIZE_T_ONE)) << (((i) >> 1) + TREEBIN_SHIFT - 1)))


/* ------------------------ Operations on bin maps ----------------------- */

/* bit corresponding to given index */
#define idx2bit(i)              ((binmap_t)(1) << (i))

/* Mark/Clear bits with given index */
#define mark_smallmap(M,i)      ((M)->smallmap |=  idx2bit(i))
#define clear_smallmap(M,i)     ((M)->smallmap &= ~idx2bit(i))
#define smallmap_is_marked(M,i) ((M)->smallmap &   idx2bit(i))

#define mark_treemap(M,i)       ((M)->treemap  |=  idx2bit(i))
#define clear_treemap(M,i)      ((M)->treemap  &= ~idx2bit(i))
#define treemap_is_marked(M,i)  ((M)->treemap  &   idx2bit(i))

/* isolate the least set bit of a bitmap */
#define least_bit(x)         ((x) & -(x))

/* mask with all bits to left of least bit of x on */
#define left_bits(x)         ((x<<1) | -(x<<1))

/* mask with all bits to left of or equal to least bit of x on */
#define same_or_left_bits(x) ((x) | -(x))

/* index corresponding to given bit. Use x86 asm if possible */

#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
#define compute_bit2idx(X, I)\
{\
  unsigned int J;\
  J = __builtin_ctz(X); \
  I = (bindex_t)J;\
}

#elif defined (__INTEL_COMPILER)
#define compute_bit2idx(X, I)\
{\
  unsigned int J;\
  J = _bit_scan_forward (X); \
  I = (bindex_t)J;\
}

#elif defined(_MSC_VER) && _MSC_VER>=1300
#define compute_bit2idx(X, I)\
{\
  unsigned int J;\
  _BitScanForward((DWORD *) &J, X);\
  I = (bindex_t)J;\
}

#elif USE_BUILTIN_FFS
#define compute_bit2idx(X, I) I = ffs(X)-1

#else
#define compute_bit2idx(X, I)\
{\
  unsigned int Y = X - 1;\
  unsigned int K = Y >> (16-4) & 16;\
  unsigned int N = K;        Y >>= K;\
  N += K = Y >> (8-3) &  8;  Y >>= K;\
  N += K = Y >> (4-2) &  4;  Y >>= K;\
  N += K = Y >> (2-1) &  2;  Y >>= K;\
  N += K = Y >> (1-0) &  1;  Y >>= K;\
  I = (bindex_t)(N + Y);\
}
#endif /* GNUC */


/* ----------------------- Runtime Check Support ------------------------- */

/*
  For security, the main invariant is that malloc/free/etc never
  writes to a static address other than malloc_state, unless static
  malloc_state itself has been corrupted, which cannot occur via
  malloc (because of these checks). In essence this means that we
  believe all pointers, sizes, maps etc held in malloc_state, but
  check all of those linked or offsetted from other embedded data
  structures.  These checks are interspersed with main code in a way
  that tends to minimize their run-time cost.

  When FOOTERS is defined, in addition to range checking, we also
  verify footer fields of inuse chunks, which can be used guarantee
  that the mstate controlling malloc/free is intact.  This is a
  streamlined version of the approach described by William Robertson
  et al in "Run-time Detection of Heap-based Overflows" LISA'03
  http://www.usenix.org/events/lisa03/tech/robertson.html The footer
  of an inuse chunk holds the xor of its mstate and a random seed,
  that is checked upon calls to free() and realloc().  This is
  (probabilistically) unguessable from outside the program, but can be
  computed by any code successfully malloc'ing any chunk, so does not
  itself provide protection against code that has already broken
  security through some other means.  Unlike Robertson et al, we
  always dynamically check addresses of all offset chunks (previous,
  next, etc). This turns out to be cheaper than relying on hashes.
*/

#if !INSECURE
/* Check if address a is at least as high as any from MORECORE or MMAP */
#define ok_address(M, a) ((char*)(a) >= (M)->least_addr)
/* Check if address of next chunk n is higher than base chunk p */
#define ok_next(p, n)    ((char*)(p) < (char*)(n))
/* Check if p has inuse status */
#define ok_inuse(p)     is_inuse(p)
/* Check if p has its pinuse bit on */
#define ok_pinuse(p)     pinuse(p)

#else /* !INSECURE */
#define ok_address(M, a) (1)
#define ok_next(b, n)    (1)
#define ok_inuse(p)      (1)
#define ok_pinuse(p)     (1)
#endif /* !INSECURE */

#if (FOOTERS && !INSECURE)
/* Check if (alleged) mstate m has expected magic field */
CLIB_NOSANITIZE_ADDR
static inline int
ok_magic (const mstate m)
{
    return (m->magic == mparams.magic);
}
#else  /* (FOOTERS && !INSECURE) */
#define ok_magic(M)      (1)
#endif /* (FOOTERS && !INSECURE) */

/* In gcc, use __builtin_expect to minimize impact of checks */
#if !INSECURE
#if defined(__GNUC__) && __GNUC__ >= 3
#define RTCHECK(e)  __builtin_expect(e, 1)
#else /* GNUC */
#define RTCHECK(e)  (e)
#endif /* GNUC */
#else /* !INSECURE */
#define RTCHECK(e)  (1)
#endif /* !INSECURE */

/* macros to set up inuse chunks with or without footers */

#if !FOOTERS

#define mark_inuse_foot(M,p,s)

/* Macros for setting head/foot of non-mmapped chunks */

/* Set cinuse bit and pinuse bit of next chunk */
#define set_inuse(M,p,s)\
  ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
  ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)

/* Set cinuse and pinuse of this chunk and pinuse of next chunk */
#define set_inuse_and_pinuse(M,p,s)\
  ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
  ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)

/* Set size, cinuse and pinuse bit of this chunk */
#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
  ((p)->head = (s|PINUSE_BIT|CINUSE_BIT))

#else /* FOOTERS */

/* Set foot of inuse chunk to be xor of mstate and seed */
#define mark_inuse_foot(M,p,s)\
  (((mchunkptr)((char*)(p) + (s)))->prev_foot = ((size_t)(M) ^ mparams.magic))

#define get_mstate_for(p)\
  ((mstate)(((mchunkptr)((char*)(p) +\
    (chunksize(p))))->prev_foot ^ mparams.magic))

#define set_inuse(M,p,s)\
  ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
  (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT), \
  mark_inuse_foot(M,p,s))

#define set_inuse_and_pinuse(M,p,s)\
  ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
  (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT),\
 mark_inuse_foot(M,p,s))

#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
  ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
  mark_inuse_foot(M, p, s))

#endif /* !FOOTERS */

/* ---------------------------- setting mparams -------------------------- */

#if LOCK_AT_FORK
static void pre_fork(void)         { ACQUIRE_LOCK(&(gm)->mutex); }
static void post_fork_parent(void) { RELEASE_LOCK(&(gm)->mutex); }
static void post_fork_child(void)  { INITIAL_LOCK(&(gm)->mutex); }
#endif /* LOCK_AT_FORK */

/* Initialize mparams */
static int init_mparams(void) {
#ifdef NEED_GLOBAL_LOCK_INIT
  if (malloc_global_mutex_status <= 0)
    init_malloc_global_mutex();
#endif

  ACQUIRE_MALLOC_GLOBAL_LOCK();
  if (mparams.magic == 0) {
    size_t magic;
    size_t psize;
    size_t gsize;

#ifndef WIN32
    psize = malloc_getpagesize;
    gsize = ((DEFAULT_GRANULARITY != 0)? DEFAULT_GRANULARITY : psize);
#else /* WIN32 */
    {
      SYSTEM_INFO system_info;
      GetSystemInfo(&system_info);
      psize = system_info.dwPageSize;
      gsize = ((DEFAULT_GRANULARITY != 0)?
               DEFAULT_GRANULARITY : system_info.dwAllocationGranularity);
    }
#endif /* WIN32 */

    /* Sanity-check configuration:
       size_t must be unsigned and as wide as pointer type.
       ints must be at least 4 bytes.
       alignment must be at least 8.
       Alignment, min chunk size, and page size must all be powers of 2.
    */
    if ((sizeof(size_t) != sizeof(char*)) ||
        (MAX_SIZE_T < MIN_CHUNK_SIZE)  ||
        (sizeof(int) < 4)  ||
        (MALLOC_ALIGNMENT < (size_t)8U) ||
        ((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT-SIZE_T_ONE)) != 0) ||
        ((MCHUNK_SIZE      & (MCHUNK_SIZE-SIZE_T_ONE))      != 0) ||
        ((gsize            & (gsize-SIZE_T_ONE))            != 0) ||
        ((psize            & (psize-SIZE_T_ONE))            != 0))
      DLM_ABORT;
    mparams.granularity = gsize;
    mparams.page_size = psize;
    mparams.mmap_threshold = DEFAULT_MMAP_THRESHOLD;
    mparams.trim_threshold = DEFAULT_TRIM_THRESHOLD;
#if MORECORE_CONTIGUOUS
    mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT;
#else  /* MORECORE_CONTIGUOUS */
    mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT|USE_NONCONTIGUOUS_BIT;
#endif /* MORECORE_CONTIGUOUS */

#if !ONLY_MSPACES
    /* Set up lock for main malloc area */
    gm->mflags = mparams.default_mflags;
    (void)INITIAL_LOCK(&gm->mutex);
#endif
#if LOCK_AT_FORK
    pthread_atfork(&pre_fork, &post_fork_parent, &post_fork_child);
#endif

    {
#ifndef DLM_MAGIC_CONSTANT
#if USE_DEV_RANDOM
      int fd;
      unsigned char buf[sizeof(size_t)];
      /* Try to use /dev/urandom, else fall back on using time */
      if ((fd = open("/dev/urandom", O_RDONLY)) >= 0 &&
          read(fd, buf, sizeof(buf)) == sizeof(buf)) {
        magic = *((size_t *) buf);
        close(fd);
      }
      else
#endif /* USE_DEV_RANDOM */
#ifdef WIN32
      magic = (size_t)(GetTickCount() ^ (size_t)0x55555555U);
#elif defined(LACKS_TIME_H)
      magic = (size_t)&magic ^ (size_t)0x55555555U;
#else
      magic = (size_t)(time(0) ^ (size_t)0x55555555U);
#endif
      magic |= (size_t)8U;    /* ensure nonzero */
      magic &= ~(size_t)7U;   /* improve chances of fault for bad values */
#else
      magic = DLM_MAGIC_CONSTANT;
#endif
      /* Until memory modes commonly available, use volatile-write */
      (*(volatile size_t *)(&(mparams.magic))) = magic;
    }
  }

  RELEASE_MALLOC_GLOBAL_LOCK();
  return 1;
}

/* support for mallopt */
static int change_mparam(int param_number, int value) {
  size_t val;
  ensure_initialization();
  val = (value == -1)? MAX_SIZE_T : (size_t)value;
  switch(param_number) {
  case M_TRIM_THRESHOLD:
    mparams.trim_threshold = val;
    return 1;
  case M_GRANULARITY:
    if (val >= mparams.page_size && ((val & (val-1)) == 0)) {
      mparams.granularity = val;
      return 1;
    }
    else
      return 0;
  case M_MMAP_THRESHOLD:
    mparams.mmap_threshold = val;
    return 1;
  default:
    return 0;
  }
}

#if DEBUG
/* ------------------------- Debugging Support --------------------------- */

/* Check properties of any chunk, whether free, inuse, mmapped etc  */
static void do_check_any_chunk(mstate m, mchunkptr p) {
  assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
  assert(ok_address(m, p));
}

/* Check properties of top chunk */
static void do_check_top_chunk(mstate m, mchunkptr p) {
  msegmentptr sp = segment_holding(m, (char*)p);
  size_t  sz = p->head & ~INUSE_BITS; /* third-lowest bit can be set! */
  assert(sp != 0);
  assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
  assert(ok_address(m, p));
  assert(sz == m->topsize);
  assert(sz > 0);
  assert(sz == ((sp->base + sp->size) - (char*)p) - TOP_FOOT_SIZE);
  assert(pinuse(p));
  assert(!pinuse(chunk_plus_offset(p, sz)));
}

/* Check properties of (inuse) mmapped chunks */
static void do_check_mmapped_chunk(mstate m, mchunkptr p) {
  size_t  sz = chunksize(p);
  size_t len = (sz + (p->prev_foot) + MMAP_FOOT_PAD);
  assert(is_mmapped(p));
  assert(use_mmap(m));
  assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
  assert(ok_address(m, p));
  assert(!is_small(sz));
  assert((len & (mparams.page_size-SIZE_T_ONE)) == 0);
  assert(chunk_plus_offset(p, sz)->head == FENCEPOST_HEAD);
  assert(chunk_plus_offset(p, sz+SIZE_T_SIZE)->head == 0);
}

/* Check properties of inuse chunks */
static void do_check_inuse_chunk(mstate m, mchunkptr p) {
  do_check_any_chunk(m, p);
  assert(is_inuse(p));
  assert(next_pinuse(p));
  /* If not pinuse and not mmapped, previous chunk has OK offset */
  assert(is_mmapped(p) || pinuse(p) || next_chunk(prev_chunk(p)) == p);
  if (is_mmapped(p))
    do_check_mmapped_chunk(m, p);
}

/* Check properties of free chunks */
static void do_check_free_chunk(mstate m, mchunkptr p) {
  size_t sz = chunksize(p);
  mchunkptr next = chunk_plus_offset(p, sz);
  do_check_any_chunk(m, p);
  assert(!is_inuse(p));
  assert(!next_pinuse(p));
  assert (!is_mmapped(p));
  if (p != m->dv && p != m->top) {
    if (sz >= MIN_CHUNK_SIZE) {
      assert((sz & CHUNK_ALIGN_MASK) == 0);
      assert(is_aligned(chunk2mem(p)));
      assert(next->prev_foot == sz);
      assert(pinuse(p));
      assert (next == m->top || is_inuse(next));
      assert(p->fd->bk == p);
      assert(p->bk->fd == p);
    }
    else  /* markers are always of size SIZE_T_SIZE */
      assert(sz == SIZE_T_SIZE);
  }
}

/* Check properties of malloced chunks at the point they are malloced */
static void do_check_malloced_chunk(mstate m, void* mem, size_t s) {
  if (mem != 0) {
    mchunkptr p = mem2chunk(mem);
    size_t sz = p->head & ~INUSE_BITS;
    do_check_inuse_chunk(m, p);
    assert((sz & CHUNK_ALIGN_MASK) == 0);
    assert(sz >= MIN_CHUNK_SIZE);
    assert(sz >= s);
    /* unless mmapped, size is less than MIN_CHUNK_SIZE more than request */
    assert(is_mmapped(p) || sz < (s + MIN_CHUNK_SIZE));
  }
}

/* Check a tree and its subtrees.  */
static void do_check_tree(mstate m, tchunkptr t) {
  tchunkptr head = 0;
  tchunkptr u = t;
  bindex_t tindex = t->index;
  size_t tsize = chunksize(t);
  bindex_t idx;
  compute_tree_index(tsize, idx);
  assert(tindex == idx);
  assert(tsize >= MIN_LARGE_SIZE);
  assert(tsize >= minsize_for_tree_index(idx));
  assert((idx == NTREEBINS-1) || (tsize < minsize_for_tree_index((idx+1))));

  do { /* traverse through chain of same-sized nodes */
    do_check_any_chunk(m, ((mchunkptr)u));
    assert(u->index == tindex);
    assert(chunksize(u) == tsize);
    assert(!is_inuse(u));
    assert(!next_pinuse(u));
    assert(u->fd->bk == u);
    assert(u->bk->fd == u);
    if (u->parent == 0) {
      assert(u->child[0] == 0);
      assert(u->child[1] == 0);
    }
    else {
      assert(head == 0); /* only one node on chain has parent */
      head = u;
      assert(u->parent != u);
      assert (u->parent->child[0] == u ||
              u->parent->child[1] == u ||
              *((tbinptr*)(u->parent)) == u);
      if (u->child[0] != 0) {
        assert(u->child[0]->parent == u);
        assert(u->child[0] != u);
        do_check_tree(m, u->child[0]);
      }
      if (u->child[1] != 0) {
        assert(u->child[1]->parent == u);
        assert(u->child[1] != u);
        do_check_tree(m, u->child[1]);
      }
      if (u->child[0] != 0 && u->child[1] != 0) {
        assert(chunksize(u->child[0]) < chunksize(u->child[1]));
      }
    }
    u = u->fd;
  } while (u != t);
  assert(head != 0);
}

/*  Check all the chunks in a treebin.  */
static void do_check_treebin(mstate m, bindex_t i) {
  tbinptr* tb = treebin_at(m, i);
  tchunkptr t = *tb;
  int empty = (m->treemap & (1U << i)) == 0;
  if (t == 0)
    assert(empty);
  if (!empty)
    do_check_tree(m, t);
}

/*  Check all the chunks in a smallbin.  */
static void do_check_smallbin(mstate m, bindex_t i) {
  sbinptr b = smallbin_at(m, i);
  mchunkptr p = b->bk;
  unsigned int empty = (m->smallmap & (1U << i)) == 0;
  if (p == b)
    assert(empty);
  if (!empty) {
    for (; p != b; p = p->bk) {
      size_t size = chunksize(p);
      mchunkptr q;
      /* each chunk claims to be free */
      do_check_free_chunk(m, p);
      /* chunk belongs in bin */
      assert(small_index(size) == i);
      assert(p->bk == b || chunksize(p->bk) == chunksize(p));
      /* chunk is followed by an inuse chunk */
      q = next_chunk(p);
      if (q->head != FENCEPOST_HEAD)
        do_check_inuse_chunk(m, q);
    }
  }
}

/* Find x in a bin. Used in other check functions. */
static int bin_find(mstate m, mchunkptr x) {
  size_t size = chunksize(x);
  if (is_small(size)) {
    bindex_t sidx = small_index(size);
    sbinptr b = smallbin_at(m, sidx);
    if (smallmap_is_marked(m, sidx)) {
      mchunkptr p = b;
      do {
        if (p == x)
          return 1;
      } while ((p = p->fd) != b);
    }
  }
  else {
    bindex_t tidx;
    compute_tree_index(size, tidx);
    if (treemap_is_marked(m, tidx)) {
      tchunkptr t = *treebin_at(m, tidx);
      size_t sizebits = size << leftshift_for_tree_index(tidx);
      while (t != 0 && chunksize(t) != size) {
        t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
        sizebits <<= 1;
      }
      if (t != 0) {
        tchunkptr u = t;
        do {
          if (u == (tchunkptr)x)
            return 1;
        } while ((u = u->fd) != t);
      }
    }
  }
  return 0;
}

/* Traverse each chunk and check it; return total */
static size_t traverse_and_check(mstate m) {
  size_t sum = 0;
  if (is_initialized(m)) {
    msegmentptr s = &m->seg;
    sum += m->topsize + TOP_FOOT_SIZE;
    while (s != 0) {
      mchunkptr q = align_as_chunk(s->base);
      mchunkptr lastq = 0;
      assert(pinuse(q));
      while (segment_holds(s, q) &&
             q != m->top && q->head != FENCEPOST_HEAD) {
        sum += chunksize(q);
        if (is_inuse(q)) {
          assert(!bin_find(m, q));
          do_check_inuse_chunk(m, q);
        }
        else {
          assert(q == m->dv || bin_find(m, q));
          assert(lastq == 0 || is_inuse(lastq)); /* Not 2 consecutive free */
          do_check_free_chunk(m, q);
        }
        lastq = q;
        q = next_chunk(q);
      }
      s = s->next;
    }
  }
  return sum;
}


/* Check all properties of malloc_state. */
static void do_check_malloc_state(mstate m) {
  bindex_t i;
  size_t total;
  /* check bins */
  for (i = 0; i < NSMALLBINS; ++i)
    do_check_smallbin(m, i);
  for (i = 0; i < NTREEBINS; ++i)
    do_check_treebin(m, i);

  if (m->dvsize != 0) { /* check dv chunk */
    do_check_any_chunk(m, m->dv);
    assert(m->dvsize == chunksize(m->dv));
    assert(m->dvsize >= MIN_CHUNK_SIZE);
    assert(bin_find(m, m->dv) == 0);
  }

  if (m->top != 0) {   /* check top chunk */
    do_check_top_chunk(m, m->top);
    /*assert(m->topsize == chunksize(m->top)); redundant */
    assert(m->topsize > 0);
    assert(bin_find(m, m->top) == 0);
  }

  total = traverse_and_check(m);
  assert(total <= m->footprint);
  assert(m->footprint <= m->max_footprint);
}
#endif /* DEBUG */

/* ----------------------------- statistics ------------------------------ */

#if !NO_MALLINFO
CLIB_NOSANITIZE_ADDR
static struct dlmallinfo internal_mallinfo(mstate m) {
  struct dlmallinfo nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
  ensure_initialization();
  if (!PREACTION(m)) {
    check_malloc_state(m);
    if (is_initialized(m)) {
      size_t nfree = SIZE_T_ONE; /* top always free */
      size_t mfree = m->topsize + TOP_FOOT_SIZE;
      size_t sum = mfree;
      msegmentptr s = &m->seg;
      while (s != 0) {
        mchunkptr q = align_as_chunk(s->base);
        while (segment_holds(s, q) &&
               q != m->top && q->head != FENCEPOST_HEAD) {
          size_t sz = chunksize(q);
          sum += sz;
          if (!is_inuse(q)) {
            mfree += sz;
            ++nfree;
          }
          q = next_chunk(q);
        }
        s = s->next;
      }

      nm.arena    = sum;
      nm.ordblks  = nfree;
      nm.hblkhd   = m->footprint - sum;
      nm.usmblks  = m->max_footprint;
      nm.uordblks = m->footprint - mfree;
      nm.fordblks = mfree;
      nm.keepcost = m->topsize;
    }

    POSTACTION(m);
  }
  return nm;
}
#endif /* !NO_MALLINFO */

#if !NO_MALLOC_STATS
static void internal_malloc_stats(mstate m) {
  ensure_initialization();
  if (!PREACTION(m)) {
    size_t maxfp = 0;
    size_t fp = 0;
    size_t used = 0;
    check_malloc_state(m);
    if (is_initialized(m)) {
      msegmentptr s = &m->seg;
      maxfp = m->max_footprint;
      fp = m->footprint;
      used = fp - (m->topsize + TOP_FOOT_SIZE);

      while (s != 0) {
        mchunkptr q = align_as_chunk(s->base);
        while (segment_holds(s, q) &&
               q != m->top && q->head != FENCEPOST_HEAD) {
          if (!is_inuse(q))
            used -= chunksize(q);
          q = next_chunk(q);
        }
        s = s->next;
      }
    }
    POSTACTION(m); /* drop lock */
    fprintf(stderr, "max system bytes = %10lu\n", (unsigned long)(maxfp));
    fprintf(stderr, "system bytes     = %10lu\n", (unsigned long)(fp));
    fprintf(stderr, "in use bytes     = %10lu\n", (unsigned long)(used));
  }
}
#endif /* NO_MALLOC_STATS */

/* ----------------------- Operations on smallbins ----------------------- */

/*
  Various forms of linking and unlinking are defined as macros.  Even
  the ones for trees, which are very long but have very short typical
  paths.  This is ugly but reduces reliance on inlining support of
  compilers.
*/

/* Link a free chunk into a smallbin  */
#define insert_small_chunk(M, P, S) {\
  bindex_t I  = small_index(S);\
  mchunkptr B = smallbin_at(M, I);\
  mchunkptr F = B;\
  assert(S >= MIN_CHUNK_SIZE);\
  if (!smallmap_is_marked(M, I))\
    mark_smallmap(M, I);\
  else if (RTCHECK(ok_address(M, B->fd)))\
    F = B->fd;\
  else {\
    CORRUPTION_ERROR_ACTION(M);\
  }\
  B->fd = P;\
  F->bk = P;\
  P->fd = F;\
  P->bk = B;\
}

/* Unlink a chunk from a smallbin  */
#define unlink_small_chunk(M, P, S) {\
  mchunkptr F = P->fd;\
  mchunkptr B = P->bk;\
  bindex_t I = small_index(S);\
  assert(P != B);\
  assert(P != F);\
  assert(chunksize(P) == small_index2size(I));\
  if (RTCHECK(F == smallbin_at(M,I) || (ok_address(M, F) && F->bk == P))) { \
    if (B == F) {\
      clear_smallmap(M, I);\
    }\
    else if (RTCHECK(B == smallbin_at(M,I) ||\
                     (ok_address(M, B) && B->fd == P))) {\
      F->bk = B;\
      B->fd = F;\
    }\
    else {\
      CORRUPTION_ERROR_ACTION(M);\
    }\
  }\
  else {\
    CORRUPTION_ERROR_ACTION(M);\
  }\
}

/* Unlink the first chunk from a smallbin */
#define unlink_first_small_chunk(M, B, P, I) {\
  mchunkptr F = P->fd;\
  assert(P != B);\
  assert(P != F);\
  assert(chunksize(P) == small_index2size(I));\
  if (B == F) {\
    clear_smallmap(M, I);\
  }\
  else if (RTCHECK(ok_address(M, F) && F->bk == P)) {\
    F->bk = B;\
    B->fd = F;\
  }\
  else {\
    CORRUPTION_ERROR_ACTION(M);\
  }\
}

/* Replace dv node, binning the old one */
/* Used only when dvsize known to be small */
#define replace_dv(M, P, S) {\
  size_t DVS = M->dvsize;\
  assert(is_small(DVS));\
  if (DVS != 0) {\
    mchunkptr DV = M->dv;\
    insert_small_chunk(M, DV, DVS);\
  }\
  M->dvsize = S;\
  M->dv = P;\
}

/* ------------------------- Operations on trees ------------------------- */

/* Insert chunk into tree */
#define insert_large_chunk(M, X, S) {\
  tbinptr* H;\
  bindex_t I;\
  compute_tree_index(S, I);\
  H = treebin_at(M, I);\
  X->index = I;\
  X->child[0] = X->child[1] = 0;\
  if (!treemap_is_marked(M, I)) {\
    mark_treemap(M, I);\
    *H = X;\
    X->parent = (tchunkptr)H;\
    X->fd = X->bk = X;\
  }\
  else {\
    tchunkptr T = *H;\
    size_t K = S << leftshift_for_tree_index(I);\
    for (;;) {\
      if (chunksize(T) != S) {\
        tchunkptr* C = &(T->child[(K >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1]);\
        K <<= 1;\
        if (*C != 0)\
          T = *C;\
        else if (RTCHECK(ok_address(M, C))) {\
          *C = X;\
          X->parent = T;\
          X->fd = X->bk = X;\
          break;\
        }\
        else {\
          CORRUPTION_ERROR_ACTION(M);\
          break;\
        }\
      }\
      else {\
        tchunkptr F = T->fd;\
        if (RTCHECK(ok_address(M, T) && ok_address(M, F))) {\
          T->fd = F->bk = X;\
          X->fd = F;\
          X->bk = T;\
          X->parent = 0;\
          break;\
        }\
        else {\
          CORRUPTION_ERROR_ACTION(M);\
          break;\
        }\
      }\
    }\
  }\
}

/*
  Unlink steps:

  1. If x is a chained node, unlink it from its same-sized fd/bk links
     and choose its bk node as its replacement.
  2. If x was the last node of its size, but not a leaf node, it must
     be replaced with a leaf node (not merely one with an open left or
     right), to make sure that lefts and rights of descendents
     correspond properly to bit masks.  We use the rightmost descendent
     of x.  We could use any other leaf, but this is easy to locate and
     tends to counteract removal of leftmosts elsewhere, and so keeps
     paths shorter than minimally guaranteed.  This doesn't loop much
     because on average a node in a tree is near the bottom.
  3. If x is the base of a chain (i.e., has parent links) relink
     x's parent and children to x's replacement (or null if none).
*/

#define unlink_large_chunk(M, X) {\
  tchunkptr XP = X->parent;\
  tchunkptr R;\
  if (X->bk != X) {\
    tchunkptr F = X->fd;\
    R = X->bk;\
    if (RTCHECK(ok_address(M, F) && F->bk == X && R->fd == X)) {\
      F->bk = R;\
      R->fd = F;\
    }\
    else {\
      CORRUPTION_ERROR_ACTION(M);\
    }\
  }\
  else {\
    tchunkptr* RP;\
    if (((R = *(RP = &(X->child[1]))) != 0) ||\
        ((R = *(RP = &(X->child[0]))) != 0)) {\
      tchunkptr* CP;\
      while ((*(CP = &(R->child[1])) != 0) ||\
             (*(CP = &(R->child[0])) != 0)) {\
        R = *(RP = CP);\
      }\
      if (RTCHECK(ok_address(M, RP)))\
        *RP = 0;\
      else {\
        CORRUPTION_ERROR_ACTION(M);\
      }\
    }\
  }\
  if (XP != 0) {\
    tbinptr* H = treebin_at(M, X->index);\
    if (X == *H) {\
      if ((*H = R) == 0) \
        clear_treemap(M, X->index);\
    }\
    else if (RTCHECK(ok_address(M, XP))) {\
      if (XP->child[0] == X) \
        XP->child[0] = R;\
      else \
        XP->child[1] = R;\
    }\
    else\
      CORRUPTION_ERROR_ACTION(M);\
    if (R != 0) {\
      if (RTCHECK(ok_address(M, R))) {\
        tchunkptr C0, C1;\
        R->parent = XP;\
        if ((C0 = X->child[0]) != 0) {\
          if (RTCHECK(ok_address(M, C0))) {\
            R->child[0] = C0;\
            C0->parent = R;\
          }\
          else\
            CORRUPTION_ERROR_ACTION(M);\
        }\
        if ((C1 = X->child[1]) != 0) {\
          if (RTCHECK(ok_address(M, C1))) {\
            R->child[1] = C1;\
            C1->parent = R;\
          }\
          else\
            CORRUPTION_ERROR_ACTION(M);\
        }\
      }\
      else\
        CORRUPTION_ERROR_ACTION(M);\
    }\
  }\
}

/* Relays to large vs small bin operations */

#define insert_chunk(M, P, S)\
  if (is_small(S)) insert_small_chunk(M, P, S)\
  else { tchunkptr TP = (tchunkptr)(P); insert_large_chunk(M, TP, S); }

#define unlink_chunk(M, P, S)\
  if (is_small(S)) unlink_small_chunk(M, P, S)\
  else { tchunkptr TP = (tchunkptr)(P); unlink_large_chunk(M, TP); }


/* Relays to internal calls to malloc/free from realloc, memalign etc */

#if ONLY_MSPACES
#define internal_malloc(m, b) mspace_malloc(m, b)
#define internal_free(m, mem) mspace_free(m,mem);
#else /* ONLY_MSPACES */
#if MSPACES
#define internal_malloc(m, b)\
  ((m == gm)? dlmalloc(b) : mspace_malloc(m, b))
#define internal_free(m, mem)\
   if (m == gm) dlfree(mem); else mspace_free(m,mem);
#else /* MSPACES */
#define internal_malloc(m, b) dlmalloc(b)
#define internal_free(m, mem) dlfree(mem)
#endif /* MSPACES */
#endif /* ONLY_MSPACES */

/* -----------------------  Direct-mmapping chunks ----------------------- */

/*
  Directly mmapped chunks are set up with an offset to the start of
  the mmapped region stored in the prev_foot field of the chunk. This
  allows reconstruction of the required argument to MUNMAP when freed,
  and also allows adjustment of the returned chunk to meet alignment
  requirements (especially in memalign).
*/

/* Malloc using mmap */
static void* mmap_alloc(mstate m, size_t nb) {
  size_t mmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
  if (m->footprint_limit != 0) {
    size_t fp = m->footprint + mmsize;
    if (fp <= m->footprint || fp > m->footprint_limit)
      return 0;
  }
  if (mmsize > nb) {     /* Check for wrap around 0 */
    char* mm = (char*)(CALL_DIRECT_MMAP(mmsize));
    if (mm != CMFAIL) {
      size_t offset = align_offset(chunk2mem(mm));
      size_t psize = mmsize - offset - MMAP_FOOT_PAD;
      mchunkptr p = (mchunkptr)(mm + offset);
      p->prev_foot = offset;
      p->head = psize;
      mark_inuse_foot(m, p, psize);
      chunk_plus_offset(p, psize)->head = FENCEPOST_HEAD;
      chunk_plus_offset(p, psize+SIZE_T_SIZE)->head = 0;

      if (m->least_addr == 0 || mm < m->least_addr)
        m->least_addr = mm;
      if ((m->footprint += mmsize) > m->max_footprint)
        m->max_footprint = m->footprint;
      assert(is_aligned(chunk2mem(p)));
      check_mmapped_chunk(m, p);
      return chunk2mem(p);
    }
  }
  return 0;
}

/* Realloc using mmap */
static mchunkptr mmap_resize(mstate m, mchunkptr oldp, size_t nb, int flags) {
  size_t oldsize = chunksize(oldp);
  (void)flags; /* placate people compiling -Wunused */
  if (is_small(nb)) /* Can't shrink mmap regions below small size */
    return 0;
  /* Keep old chunk if big enough but not too big */
  if (oldsize >= nb + SIZE_T_SIZE &&
      (oldsize - nb) <= (mparams.granularity << 1))
    return oldp;
  else {
    size_t offset = oldp->prev_foot;
    size_t oldmmsize = oldsize + offset + MMAP_FOOT_PAD;
    size_t newmmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
    char* cp = (char*)CALL_MREMAP((char*)oldp - offset,
                                  oldmmsize, newmmsize, flags);
    if (cp != CMFAIL) {
      mchunkptr newp = (mchunkptr)(cp + offset);
      size_t psize = newmmsize - offset - MMAP_FOOT_PAD;
      newp->head = psize;
      mark_inuse_foot(m, newp, psize);
      chunk_plus_offset(newp, psize)->head = FENCEPOST_HEAD;
      chunk_plus_offset(newp, psize+SIZE_T_SIZE)->head = 0;

      if (cp < m->least_addr)
        m->least_addr = cp;
      if ((m->footprint += newmmsize - oldmmsize) > m->max_footprint)
        m->max_footprint = m->footprint;
      check_mmapped_chunk(m, newp);
      return newp;
    }
  }
  return 0;
}


/* -------------------------- mspace management -------------------------- */

/* Initialize top chunk and its size */
CLIB_NOSANITIZE_ADDR
static void init_top(mstate m, mchunkptr p, size_t psize) {
  /* Ensure alignment */
  size_t offset = align_offset(chunk2mem(p));
  p = (mchunkptr)((char*)p + offset);
  psize -= offset;

  m->top = p;
  m->topsize = psize;
  p->head = psize | PINUSE_BIT;
  /* set size of fake trailing chunk holding overhead space only once */
  chunk_plus_offset(p, psize)->head = TOP_FOOT_SIZE;
  m->trim_check = mparams.trim_threshold; /* reset on each update */
}

/* Initialize bins for a new mstate that is otherwise zeroed out */
static void init_bins(mstate m) {
  /* Establish circular links for smallbins */
  bindex_t i;
  for (i = 0; i < NSMALLBINS; ++i) {
    sbinptr bin = smallbin_at(m,i);
    bin->fd = bin->bk = bin;
  }
}

#if PROCEED_ON_ERROR

/* default corruption action */
static void reset_on_error(mstate m) {
  int i;
  ++malloc_corruption_error_count;
  /* Reinitialize fields to forget about all memory */
  m->smallmap = m->treemap = 0;
  m->dvsize = m->topsize = 0;
  m->seg.base = 0;
  m->seg.size = 0;
  m->seg.next = 0;
  m->top = m->dv = 0;
  for (i = 0; i < NTREEBINS; ++i)
    *treebin_at(m, i) = 0;
  init_bins(m);
}
#endif /* PROCEED_ON_ERROR */

/* Allocate chunk and prepend remainder with chunk in successor base. */
CLIB_NOSANITIZE_ADDR
static void* prepend_alloc(mstate m, char* newbase, char* oldbase,
                           size_t nb) {
  mchunkptr p = align_as_chunk(newbase);
  mchunkptr oldfirst = align_as_chunk(oldbase);
  size_t psize = (char*)oldfirst - (char*)p;
  mchunkptr q = chunk_plus_offset(p, nb);
  size_t qsize = psize - nb;
  set_size_and_pinuse_of_inuse_chunk(m, p, nb);

  assert((char*)oldfirst > (char*)q);
  assert(pinuse(oldfirst));
  assert(qsize >= MIN_CHUNK_SIZE);

  /* consolidate remainder with first chunk of old base */
  if (oldfirst == m->top) {
    size_t tsize = m->topsize += qsize;
    m->top = q;
    q->head = tsize | PINUSE_BIT;
    check_top_chunk(m, q);
  }
  else if (oldfirst == m->dv) {
    size_t dsize = m->dvsize += qsize;
    m->dv = q;
    set_size_and_pinuse_of_free_chunk(q, dsize);
  }
  else {
    if (!is_inuse(oldfirst)) {
      size_t nsize = chunksize(oldfirst);
      unlink_chunk(m, oldfirst, nsize);
      oldfirst = chunk_plus_offset(oldfirst, nsize);
      qsize += nsize;
    }
    set_free_with_pinuse(q, qsize, oldfirst);
    insert_chunk(m, q, qsize);
    check_free_chunk(m, q);
  }

  check_malloced_chunk(m, chunk2mem(p), nb);
  return chunk2mem(p);
}

/* Add a segment to hold a new noncontiguous region */
CLIB_NOSANITIZE_ADDR
static void add_segment(mstate m, char* tbase, size_t tsize, flag_t mmapped) {
  /* Determine locations and sizes of segment, fenceposts, old top */
  char* old_top = (char*)m->top;
  msegmentptr oldsp = segment_holding(m, old_top);
  char* old_end = oldsp->base + oldsp->size;
  size_t ssize = pad_request(sizeof(struct malloc_segment));
  char* rawsp = old_end - (ssize + FOUR_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
  size_t offset = align_offset(chunk2mem(rawsp));
  char* asp = rawsp + offset;
  char* csp = (asp < (old_top + MIN_CHUNK_SIZE))? old_top : asp;
  mchunkptr sp = (mchunkptr)csp;
  msegmentptr ss = (msegmentptr)(chunk2mem(sp));
  mchunkptr tnext = chunk_plus_offset(sp, ssize);
  mchunkptr p = tnext;
  int nfences = 0;

  /* reset top to new space */
  init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);

  /* Set up segment record */
  assert(is_aligned(ss));
  set_size_and_pinuse_of_inuse_chunk(m, sp, ssize);
  *ss = m->seg; /* Push current record */
  m->seg.base = tbase;
  m->seg.size = tsize;
  m->seg.sflags = mmapped;
  m->seg.next = ss;

  /* Insert trailing fenceposts */
  for (;;) {
    mchunkptr nextp = chunk_plus_offset(p, SIZE_T_SIZE);
    p->head = FENCEPOST_HEAD;
    ++nfences;
    if ((char*)(&(nextp->head)) < old_end)
      p = nextp;
    else
      break;
  }
  assert(nfences >= 2);

  /* Insert the rest of old top into a bin as an ordinary free chunk */
  if (csp != old_top) {
    mchunkptr q = (mchunkptr)old_top;
    size_t psize = csp - old_top;
    mchunkptr tn = chunk_plus_offset(q, psize);
    set_free_with_pinuse(q, psize, tn);
    insert_chunk(m, q, psize);
  }

  check_top_chunk(m, m->top);
}

/* -------------------------- System allocation -------------------------- */

/* Get memory from system using MORECORE or MMAP */
CLIB_NOSANITIZE_ADDR
static void* sys_alloc(mstate m, size_t nb) {
  char* tbase = CMFAIL;
  size_t tsize = 0;
  flag_t mmap_flag = 0;
  size_t asize; /* allocation size */

  ensure_initialization();

  if (use_noexpand(m))
      return 0;

  /* Directly map large chunks, but only if already initialized */
  if (use_mmap(m) && nb >= mparams.mmap_threshold && m->topsize != 0) {
    void* mem = mmap_alloc(m, nb);
    if (mem != 0)
      return mem;
  }

  asize = granularity_align(nb + SYS_ALLOC_PADDING);
  if (asize <= nb)
    return 0; /* wraparound */
  if (m->footprint_limit != 0) {
    size_t fp = m->footprint + asize;
    if (fp <= m->footprint || fp > m->footprint_limit)
      return 0;
  }

  /*
    Try getting memory in any of three ways (in most-preferred to
    least-preferred order):
    1. A call to MORECORE that can normally contiguously extend memory.
       (disabled if not MORECORE_CONTIGUOUS or not HAVE_MORECORE or
       or main space is mmapped or a previous contiguous call failed)
    2. A call to MMAP new space (disabled if not HAVE_MMAP).
       Note that under the default settings, if MORECORE is unable to
       fulfill a request, and HAVE_MMAP is true, then mmap is
       used as a noncontiguous system allocator. This is a useful backup
       strategy for systems with holes in address spaces -- in this case
       sbrk cannot contiguously expand the heap, but mmap may be able to
       find space.
    3. A call to MORECORE that cannot usually contiguously extend memory.
       (disabled if not HAVE_MORECORE)

   In all cases, we need to request enough bytes from system to ensure
   we can malloc nb bytes upon success, so pad with enough space for
   top_foot, plus alignment-pad to make sure we don't lose bytes if
   not on boundary, and round this up to a granularity unit.
  */

  if (MORECORE_CONTIGUOUS && !use_noncontiguous(m)) {
    char* br = CMFAIL;
    size_t ssize = asize; /* sbrk call size */
    msegmentptr ss = (m->top == 0)? 0 : segment_holding(m, (char*)m->top);
    ACQUIRE_MALLOC_GLOBAL_LOCK();

    if (ss == 0) {  /* First time through or recovery */
      char* base = (char*)CALL_MORECORE(0);
      if (base != CMFAIL) {
        size_t fp;
        /* Adjust to end on a page boundary */
        if (!is_page_aligned(base))
          ssize += (page_align((size_t)base) - (size_t)base);
        fp = m->footprint + ssize; /* recheck limits */
        if (ssize > nb && ssize < HALF_MAX_SIZE_T &&
            (m->footprint_limit == 0 ||
             (fp > m->footprint && fp <= m->footprint_limit)) &&
            (br = (char*)(CALL_MORECORE(ssize))) == base) {
          tbase = base;
          tsize = ssize;
        }
      }
    }
    else {
      /* Subtract out existing available top space from MORECORE request. */
      ssize = granularity_align(nb - m->topsize + SYS_ALLOC_PADDING);
      /* Use mem here only if it did continuously extend old space */
      if (ssize < HALF_MAX_SIZE_T &&
          (br = (char*)(CALL_MORECORE(ssize))) == ss->base+ss->size) {
        tbase = br;
        tsize = ssize;
      }
    }

    if (tbase == CMFAIL) {    /* Cope with partial failure */
      if (br != CMFAIL) {    /* Try to use/extend the space we did get */
        if (ssize < HALF_MAX_SIZE_T &&
            ssize < nb + SYS_ALLOC_PADDING) {
          size_t esize = granularity_align(nb + SYS_ALLOC_PADDING - ssize);
          if (esize < HALF_MAX_SIZE_T) {
            char* end = (char*)CALL_MORECORE(esize);
            if (end != CMFAIL)
              ssize += esize;
            else {            /* Can't use; try to release */
              (void) CALL_MORECORE(-ssize);
              br = CMFAIL;
            }
          }
        }
      }
      if (br != CMFAIL) {    /* Use the space we did get */
        tbase = br;
        tsize = ssize;
      }
      else
        disable_contiguous(m); /* Don't try contiguous path in the future */
    }

    RELEASE_MALLOC_GLOBAL_LOCK();
  }

  if (HAVE_MMAP && tbase == CMFAIL) {  /* Try MMAP */
    char* mp = (char*)(CALL_MMAP(asize));
    if (mp != CMFAIL) {
      tbase = mp;
      tsize = asize;
      mmap_flag = USE_MMAP_BIT;
    }
  }

  if (HAVE_MORECORE && tbase == CMFAIL) { /* Try noncontiguous MORECORE */
    if (asize < HALF_MAX_SIZE_T) {
      char* br = CMFAIL;
      char* end = CMFAIL;
      ACQUIRE_MALLOC_GLOBAL_LOCK();
      br = (char*)(CALL_MORECORE(asize));
      end = (char*)(CALL_MORECORE(0));
      RELEASE_MALLOC_GLOBAL_LOCK();
      if (br != CMFAIL && end != CMFAIL && br < end) {
        size_t ssize = end - br;
        if (ssize > nb + TOP_FOOT_SIZE) {
          tbase = br;
          tsize = ssize;
        }
      }
    }
  }

  if (tbase != CMFAIL) {

    if ((m->footprint += tsize) > m->max_footprint)
      m->max_footprint = m->footprint;

    if (!is_initialized(m)) { /* first-time initialization */
      if (m->least_addr == 0 || tbase < m->least_addr)
        m->least_addr = tbase;
      m->seg.base = tbase;
      m->seg.size = tsize;
      m->seg.sflags = mmap_flag;
      m->magic = mparams.magic;
      m->release_checks = MAX_RELEASE_CHECK_RATE;
      init_bins(m);
#if !ONLY_MSPACES
      if (is_global(m))
        init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
      else
#endif
      {
        /* Offset top by embedded malloc_state */
        mchunkptr mn = next_chunk(mem2chunk(m));
        init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) -TOP_FOOT_SIZE);
      }
    }

    else {
      /* Try to merge with an existing segment */
      msegmentptr sp = &m->seg;
      /* Only consider most recent segment if traversal suppressed */
      while (sp != 0 && tbase != sp->base + sp->size)
        sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
      if (sp != 0 &&
          !is_extern_segment(sp) &&
          (sp->sflags & USE_MMAP_BIT) == mmap_flag &&
          segment_holds(sp, m->top)) { /* append */
        sp->size += tsize;
        init_top(m, m->top, m->topsize + tsize);
      }
      else {
        if (tbase < m->least_addr)
          m->least_addr = tbase;
        sp = &m->seg;
        while (sp != 0 && sp->base != tbase + tsize)
          sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
        if (sp != 0 &&
            !is_extern_segment(sp) &&
            (sp->sflags & USE_MMAP_BIT) == mmap_flag) {
          char* oldbase = sp->base;
          sp->base = tbase;
          sp->size += tsize;
          return prepend_alloc(m, tbase, oldbase, nb);
        }
        else
          add_segment(m, tbase, tsize, mmap_flag);
      }
    }

    if (nb < m->topsize) { /* Allocate from new or extended top space */
      size_t rsize = m->topsize -= nb;
      mchunkptr p = m->top;
      mchunkptr r = m->top = chunk_plus_offset(p, nb);
      r->head = rsize | PINUSE_BIT;
      set_size_and_pinuse_of_inuse_chunk(m, p, nb);
      check_top_chunk(m, m->top);
      check_malloced_chunk(m, chunk2mem(p), nb);
      return chunk2mem(p);
    }
  }

  MALLOC_FAILURE_ACTION;
  return 0;
}

/* -----------------------  system deallocation -------------------------- */

/* Unmap and unlink any mmapped segments that don't contain used chunks */
CLIB_NOSANITIZE_ADDR
static size_t release_unused_segments(mstate m) {
  size_t released = 0;
  int nsegs = 0;
  msegmentptr pred = &m->seg;
  msegmentptr sp = pred->next;
  while (sp != 0) {
    char* base = sp->base;
    size_t size = sp->size;
    msegmentptr next = sp->next;
    ++nsegs;
    if (is_mmapped_segment(sp) && !is_extern_segment(sp)) {
      mchunkptr p = align_as_chunk(base);
      size_t psize = chunksize(p);
      /* Can unmap if first chunk holds entire segment and not pinned */
      if (!is_inuse(p) && (char*)p + psize >= base + size - TOP_FOOT_SIZE) {
        tchunkptr tp = (tchunkptr)p;
        assert(segment_holds(sp, (char*)sp));
        if (p == m->dv) {
          m->dv = 0;
          m->dvsize = 0;
        }
        else {
          unlink_large_chunk(m, tp);
        }
        if (CALL_MUNMAP(base, size) == 0) {
          released += size;
          m->footprint -= size;
          /* unlink obsoleted record */
          sp = pred;
          sp->next = next;
        }
        else { /* back out if cannot unmap */
          insert_large_chunk(m, tp, psize);
        }
      }
    }
    if (NO_SEGMENT_TRAVERSAL) /* scan only first segment */
      break;
    pred = sp;
    sp = next;
  }
  /* Reset check counter */
  m->release_checks = (((size_t) nsegs > (size_t) MAX_RELEASE_CHECK_RATE)?
                       (size_t) nsegs : (size_t) MAX_RELEASE_CHECK_RATE);
  return released;
}

CLIB_NOSANITIZE_ADDR
static int sys_trim(mstate m, size_t pad) {
  size_t released = 0;
  ensure_initialization();
  if (pad < MAX_REQUEST && is_initialized(m)) {
    pad += TOP_FOOT_SIZE; /* ensure enough room for segment overhead */

    if (m->topsize > pad) {
      /* Shrink top space in granularity-size units, keeping at least one */
      size_t unit = mparams.granularity;
      size_t extra = ((m->topsize - pad + (unit - SIZE_T_ONE)) / unit -
                      SIZE_T_ONE) * unit;
      msegmentptr sp = segment_holding(m, (char*)m->top);

      if (!is_extern_segment(sp)) {
        if (is_mmapped_segment(sp)) {
          if (HAVE_MMAP &&
              sp->size >= extra &&
              !has_segment_link(m, sp)) { /* can't shrink if pinned */
            size_t newsize = sp->size - extra;
            (void)newsize; /* placate people compiling -Wunused-variable */
            /* Prefer mremap, fall back to munmap */
            if ((CALL_MREMAP(sp->base, sp->size, newsize, 0) != MFAIL) ||
                (CALL_MUNMAP(sp->base + newsize, extra) == 0)) {
              released = extra;
            }
          }
        }
        else if (HAVE_MORECORE) {
          if (extra >= HALF_MAX_SIZE_T) /* Avoid wrapping negative */
            extra = (HALF_MAX_SIZE_T) + SIZE_T_ONE - unit;
          ACQUIRE_MALLOC_GLOBAL_LOCK();
          {
            /* Make sure end of memory is where we last set it. */
            char* old_br = (char*)(CALL_MORECORE(0));
            if (old_br == sp->base + sp->size) {
              char* rel_br = (char*)(CALL_MORECORE(-extra));
              char* new_br = (char*)(CALL_MORECORE(0));
              if (rel_br != CMFAIL && new_br < old_br)
                released = old_br - new_br;
            }
          }
          RELEASE_MALLOC_GLOBAL_LOCK();
        }
      }

      if (released != 0) {
        sp->size -= released;
        m->footprint -= released;
        init_top(m, m->top, m->topsize - released);
        check_top_chunk(m, m->top);
      }
    }

    /* Unmap any unused mmapped segments */
    if (HAVE_MMAP)
      released += release_unused_segments(m);

    /* On failure, disable autotrim to avoid repeated failed future calls */
    if (released == 0 && m->topsize > m->trim_check)
      m->trim_check = MAX_SIZE_T;
  }

  return (released != 0)? 1 : 0;
}

/* Consolidate and bin a chunk. Differs from exported versions
   of free mainly in that the chunk need not be marked as inuse.
*/
CLIB_NOSANITIZE_ADDR
static void dispose_chunk(mstate m, mchunkptr p, size_t psize) {
  mchunkptr next = chunk_plus_offset(p, psize);
  if (!pinuse(p)) {
    mchunkptr prev;
    size_t prevsize = p->prev_foot;
    if (is_mmapped(p)) {
      psize += prevsize + MMAP_FOOT_PAD;
      if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
        m->footprint -= psize;
      return;
    }
    prev = chunk_minus_offset(p, prevsize);
    psize += prevsize;
    p = prev;
    if (RTCHECK(ok_address(m, prev))) { /* consolidate backward */
      if (p != m->dv) {
        unlink_chunk(m, p, prevsize);
      }
      else if ((next->head & INUSE_BITS) == INUSE_BITS) {
        m->dvsize = psize;
        set_free_with_pinuse(p, psize, next);
        return;
      }
    }
    else {
      CORRUPTION_ERROR_ACTION(m);
      return;
    }
  }
  if (RTCHECK(ok_address(m, next))) {
    if (!cinuse(next)) {  /* consolidate forward */
      if (next == m->top) {
        size_t tsize = m->topsize += psize;
        m->top = p;
        p->head = tsize | PINUSE_BIT;
        if (p == m->dv) {
          m->dv = 0;
          m->dvsize = 0;
        }
        return;
      }
      else if (next == m->dv) {
        size_t dsize = m->dvsize += psize;
        m->dv = p;
        set_size_and_pinuse_of_free_chunk(p, dsize);
        return;
      }
      else {
        size_t nsize = chunksize(next);
        psize += nsize;
        unlink_chunk(m, next, nsize);
        set_size_and_pinuse_of_free_chunk(p, psize);
        if (p == m->dv) {
          m->dvsize = psize;
          return;
        }
      }
    }
    else {
      set_free_with_pinuse(p, psize, next);
    }
    insert_chunk(m, p, psize);
  }
  else {
    CORRUPTION_ERROR_ACTION(m);
  }
}

/* ---------------------------- malloc --------------------------- */

/* allocate a large request from the best fitting chunk in a treebin */
CLIB_NOSANITIZE_ADDR
static void* tmalloc_large(mstate m, size_t nb) {
  tchunkptr v = 0;
  size_t rsize = -nb; /* Unsigned negation */
  tchunkptr t;
  bindex_t idx;
  compute_tree_index(nb, idx);
  if ((t = *treebin_at(m, idx)) != 0) {
    /* Traverse tree for this bin looking for node with size == nb */
    size_t sizebits = nb << leftshift_for_tree_index(idx);
    tchunkptr rst = 0;  /* The deepest untaken right subtree */
    for (;;) {
      tchunkptr rt;
      size_t trem = chunksize(t) - nb;
      if (trem < rsize) {
        v = t;
        if ((rsize = trem) == 0)
          break;
      }
      rt = t->child[1];
      t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
      if (rt != 0 && rt != t)
        rst = rt;
      if (t == 0) {
        t = rst; /* set t to least subtree holding sizes > nb */
        break;
      }
      sizebits <<= 1;
    }
  }
  if (t == 0 && v == 0) { /* set t to root of next non-empty treebin */
    binmap_t leftbits = left_bits(idx2bit(idx)) & m->treemap;
    if (leftbits != 0) {
      bindex_t i;
      binmap_t leastbit = least_bit(leftbits);
      compute_bit2idx(leastbit, i);
      t = *treebin_at(m, i);
    }
  }

  while (t != 0) { /* find smallest of tree or subtree */
    size_t trem = chunksize(t) - nb;
    if (trem < rsize) {
      rsize = trem;
      v = t;
    }
    t = leftmost_child(t);
  }

  /*  If dv is a better fit, return 0 so malloc will use it */
  if (v != 0 && rsize < (size_t)(m->dvsize - nb)) {
    if (RTCHECK(ok_address(m, v))) { /* split */
      mchunkptr r = chunk_plus_offset(v, nb);
      assert(chunksize(v) == rsize + nb);
      if (RTCHECK(ok_next(v, r))) {
        unlink_large_chunk(m, v);
        if (rsize < MIN_CHUNK_SIZE)
          set_inuse_and_pinuse(m, v, (rsize + nb));
        else {
          set_size_and_pinuse_of_inuse_chunk(m, v, nb);
          set_size_and_pinuse_of_free_chunk(r, rsize);
          insert_chunk(m, r, rsize);
        }
        return chunk2mem(v);
      }
    }
    CORRUPTION_ERROR_ACTION(m);
  }
  return 0;
}

/* allocate a small request from the best fitting chunk in a treebin */
CLIB_NOSANITIZE_ADDR
static void* tmalloc_small(mstate m, size_t nb) {
  tchunkptr t, v;
  size_t rsize;
  bindex_t i;
  binmap_t leastbit = least_bit(m->treemap);
  compute_bit2idx(leastbit, i);
  v = t = *treebin_at(m, i);
  rsize = chunksize(t) - nb;

  while ((t = leftmost_child(t)) != 0) {
    size_t trem = chunksize(t) - nb;
    if (trem < rsize) {
      rsize = trem;
      v = t;
    }
  }

  if (RTCHECK(ok_address(m, v))) {
    mchunkptr r = chunk_plus_offset(v, nb);
    assert(chunksize(v) == rsize + nb);
    if (RTCHECK(ok_next(v, r))) {
      unlink_large_chunk(m, v);
      if (rsize < MIN_CHUNK_SIZE)
        set_inuse_and_pinuse(m, v, (rsize + nb));
      else {
        set_size_and_pinuse_of_inuse_chunk(m, v, nb);
        set_size_and_pinuse_of_free_chunk(r, rsize);
        replace_dv(m, r, rsize);
      }
      return chunk2mem(v);
    }
  }

  CORRUPTION_ERROR_ACTION(m);
  return 0;
}

#if !ONLY_MSPACES

void* dlmalloc(size_t bytes) {
  /*
     Basic algorithm:
     If a small request (< 256 bytes minus per-chunk overhead):
       1. If one exists, use a remainderless chunk in associated smallbin.
          (Remainderless means that there are too few excess bytes to
          represent as a chunk.)
       2. If it is big enough, use the dv chunk, which is normally the
          chunk adjacent to the one used for the most recent small request.
       3. If one exists, split the smallest available chunk in a bin,
          saving remainder in dv.
       4. If it is big enough, use the top chunk.
       5. If available, get memory from system and use it
     Otherwise, for a large request:
       1. Find the smallest available binned chunk that fits, and use it
          if it is better fitting than dv chunk, splitting if necessary.
       2. If better fitting than any binned chunk, use the dv chunk.
       3. If it is big enough, use the top chunk.
       4. If request size >= mmap threshold, try to directly mmap this chunk.
       5. If available, get memory from system and use it

     The ugly goto's here ensure that postaction occurs along all paths.
  */

#if USE_LOCKS
  ensure_initialization(); /* initialize in sys_alloc if not using locks */
#endif

  if (!PREACTION(gm)) {
    void* mem;
    size_t nb;
    if (bytes <= MAX_SMALL_REQUEST) {
      bindex_t idx;
      binmap_t smallbits;
      nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
      idx = small_index(nb);
      smallbits = gm->smallmap >> idx;

      if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
        mchunkptr b, p;
        idx += ~smallbits & 1;       /* Uses next bin if idx empty */
        b = smallbin_at(gm, idx);
        p = b->fd;
        assert(chunksize(p) == small_index2size(idx));
        unlink_first_small_chunk(gm, b, p, idx);
        set_inuse_and_pinuse(gm, p, small_index2size(idx));
        mem = chunk2mem(p);
        check_malloced_chunk(gm, mem, nb);
        goto postaction;
      }

      else if (nb > gm->dvsize) {
        if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
          mchunkptr b, p, r;
          size_t rsize;
          bindex_t i;
          binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
          binmap_t leastbit = least_bit(leftbits);
          compute_bit2idx(leastbit, i);
          b = smallbin_at(gm, i);
          p = b->fd;
          assert(chunksize(p) == small_index2size(i));
          unlink_first_small_chunk(gm, b, p, i);
          rsize = small_index2size(i) - nb;
          /* Fit here cannot be remainderless if 4byte sizes */
          if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
            set_inuse_and_pinuse(gm, p, small_index2size(i));
          else {
            set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
            r = chunk_plus_offset(p, nb);
            set_size_and_pinuse_of_free_chunk(r, rsize);
            replace_dv(gm, r, rsize);
          }
          mem = chunk2mem(p);
          check_malloced_chunk(gm, mem, nb);
          goto postaction;
        }

        else if (gm->treemap != 0 && (mem = tmalloc_small(gm, nb)) != 0) {
          check_malloced_chunk(gm, mem, nb);
          goto postaction;
        }
      }
    }
    else if (bytes >= MAX_REQUEST)
      nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
    else {
      nb = pad_request(bytes);
      if (gm->treemap != 0 && (mem = tmalloc_large(gm, nb)) != 0) {
        check_malloced_chunk(gm, mem, nb);
        goto postaction;
      }
    }

    if (nb <= gm->dvsize) {
      size_t rsize = gm->dvsize - nb;
      mchunkptr p = gm->dv;
      if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
        mchunkptr r = gm->dv = chunk_plus_offset(p, nb);
        gm->dvsize = rsize;
        set_size_and_pinuse_of_free_chunk(r, rsize);
        set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
      }
      else { /* exhaust dv */
        size_t dvs = gm->dvsize;
        gm->dvsize = 0;
        gm->dv = 0;
        set_inuse_and_pinuse(gm, p, dvs);
      }
      mem = chunk2mem(p);
      check_malloced_chunk(gm, mem, nb);
      goto postaction;
    }

    else if (nb < gm->topsize) { /* Split top */
      size_t rsize = gm->topsize -= nb;
      mchunkptr p = gm->top;
      mchunkptr r = gm->top = chunk_plus_offset(p, nb);
      r->head = rsize | PINUSE_BIT;
      set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
      mem = chunk2mem(p);
      check_top_chunk(gm, gm->top);
      check_malloced_chunk(gm, mem, nb);
      goto postaction;
    }

    mem = sys_alloc(gm, nb);

  postaction:
    POSTACTION(gm);
    return mem;
  }

  return 0;
}

/* ---------------------------- free --------------------------- */

void dlfree(void* mem) {
  /*
     Consolidate freed chunks with preceding or succeeding bordering
     free chunks, if they exist, and then place in a bin.  Intermixed
     with special cases for top, dv, mmapped chunks, and usage errors.
  */

  if (mem != 0) {
    mchunkptr p  = mem2chunk(mem);
#if FOOTERS
    mstate fm = get_mstate_for(p);
    if (!ok_magic(fm)) {
      USAGE_ERROR_ACTION(fm, p);
      return;
    }
#else /* FOOTERS */
#define fm gm
#endif /* FOOTERS */
    if (!PREACTION(fm)) {
      check_inuse_chunk(fm, p);
      if (RTCHECK(ok_address(fm, p) && ok_inuse(p))) {
        size_t psize = chunksize(p);
        mchunkptr next = chunk_plus_offset(p, psize);
        if (!pinuse(p)) {
          size_t prevsize = p->prev_foot;
          if (is_mmapped(p)) {
            psize += prevsize + MMAP_FOOT_PAD;
            if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
              fm->footprint -= psize;
            goto postaction;
          }
          else {
            mchunkptr prev = chunk_minus_offset(p, prevsize);
            psize += prevsize;
            p = prev;
            if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
              if (p != fm->dv) {
                unlink_chunk(fm, p, prevsize);
              }
              else if ((next->head & INUSE_BITS) == INUSE_BITS) {
                fm->dvsize = psize;
                set_free_with_pinuse(p, psize, next);
                goto postaction;
              }
            }
            else
              goto erroraction;
          }
        }

        if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
          if (!cinuse(next)) {  /* consolidate forward */
            if (next == fm->top) {
              size_t tsize = fm->topsize += psize;
              fm->top = p;
              p->head = tsize | PINUSE_BIT;
              if (p == fm->dv) {
                fm->dv = 0;
                fm->dvsize = 0;
              }
              if (should_trim(fm, tsize))
                sys_trim(fm, 0);
              goto postaction;
            }
            else if (next == fm->dv) {
              size_t dsize = fm->dvsize += psize;
              fm->dv = p;
              set_size_and_pinuse_of_free_chunk(p, dsize);
              goto postaction;
            }
            else {
              size_t nsize = chunksize(next);
              psize += nsize;
              unlink_chunk(fm, next, nsize);
              set_size_and_pinuse_of_free_chunk(p, psize);
              if (p == fm->dv) {
                fm->dvsize = psize;
                goto postaction;
              }
            }
          }
          else
            set_free_with_pinuse(p, psize, next);

          if (is_small(psize)) {
            insert_small_chunk(fm, p, psize);
            check_free_chunk(fm, p);
          }
          else {
            tchunkptr tp = (tchunkptr)p;
            insert_large_chunk(fm, tp, psize);
            check_free_chunk(fm, p);
            if (--fm->release_checks == 0)
              release_unused_segments(fm);
          }
          goto postaction;
        }
      }
    erroraction:
      USAGE_ERROR_ACTION(fm, p);
    postaction:
      POSTACTION(fm);
    }
  }
#if !FOOTERS
#undef fm
#endif /* FOOTERS */
}

void* dlcalloc(size_t n_elements, size_t elem_size) {
  void* mem;
  size_t req = 0;
  if (n_elements != 0) {
    req = n_elements * elem_size;
    if (((n_elements | elem_size) & ~(size_t)0xffff) &&
        (req / n_elements != elem_size))
      req = MAX_SIZE_T; /* force downstream failure on overflow */
  }
  mem = dlmalloc(req);
  if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
    memset(mem, 0, req);
  return mem;
}

#endif /* !ONLY_MSPACES */

/* ------------ Internal support for realloc, memalign, etc -------------- */

/* Try to realloc; only in-place unless can_move true */
static mchunkptr try_realloc_chunk(mstate m, mchunkptr p, size_t nb,
                                   int can_move) {
  mchunkptr newp = 0;
  size_t oldsize = chunksize(p);
  mchunkptr next = chunk_plus_offset(p, oldsize);
  if (RTCHECK(ok_address(m, p) && ok_inuse(p) &&
              ok_next(p, next) && ok_pinuse(next))) {
    if (is_mmapped(p)) {
      newp = mmap_resize(m, p, nb, can_move);
    }
    else if (oldsize >= nb) {             /* already big enough */
      size_t rsize = oldsize - nb;
      if (rsize >= MIN_CHUNK_SIZE) {      /* split off remainder */
        mchunkptr r = chunk_plus_offset(p, nb);
        set_inuse(m, p, nb);
        set_inuse(m, r, rsize);
        dispose_chunk(m, r, rsize);
      }
      newp = p;
    }
    else if (next == m->top) {  /* extend into top */
      if (oldsize + m->topsize > nb) {
        size_t newsize = oldsize + m->topsize;
        size_t newtopsize = newsize - nb;
        mchunkptr newtop = chunk_plus_offset(p, nb);
        set_inuse(m, p, nb);
        newtop->head = newtopsize |PINUSE_BIT;
        m->top = newtop;
        m->topsize = newtopsize;
        newp = p;
      }
    }
    else if (next == m->dv) { /* extend into dv */
      size_t dvs = m->dvsize;
      if (oldsize + dvs >= nb) {
        size_t dsize = oldsize + dvs - nb;
        if (dsize >= MIN_CHUNK_SIZE) {
          mchunkptr r = chunk_plus_offset(p, nb);
          mchunkptr n = chunk_plus_offset(r, dsize);
          set_inuse(m, p, nb);
          set_size_and_pinuse_of_free_chunk(r, dsize);
          clear_pinuse(n);
          m->dvsize = dsize;
          m->dv = r;
        }
        else { /* exhaust dv */
          size_t newsize = oldsize + dvs;
          set_inuse(m, p, newsize);
          m->dvsize = 0;
          m->dv = 0;
        }
        newp = p;
      }
    }
    else if (!cinuse(next)) { /* extend into next free chunk */
      size_t nextsize = chunksize(next);
      if (oldsize + nextsize >= nb) {
        size_t rsize = oldsize + nextsize - nb;
        unlink_chunk(m, next, nextsize);
        if (rsize < MIN_CHUNK_SIZE) {
          size_t newsize = oldsize + nextsize;
          set_inuse(m, p, newsize);
        }
        else {
          mchunkptr r = chunk_plus_offset(p, nb);
          set_inuse(m, p, nb);
          set_inuse(m, r, rsize);
          dispose_chunk(m, r, rsize);
        }
        newp = p;
      }
    }
  }
  else {
    USAGE_ERROR_ACTION(m, chunk2mem(p));
  }
  return newp;
}

CLIB_NOSANITIZE_ADDR
static void* internal_memalign(mstate m, size_t alignment, size_t bytes) {
  void* mem = 0;
  if (alignment <  MIN_CHUNK_SIZE) /* must be at least a minimum chunk size */
    alignment = MIN_CHUNK_SIZE;
  if ((alignment & (alignment-SIZE_T_ONE)) != 0) {/* Ensure a power of 2 */
    size_t a = MALLOC_ALIGNMENT << 1;
    while (a < alignment) a <<= 1;
    alignment = a;
  }
  if (bytes >= MAX_REQUEST - alignment) {
    if (m != 0)  { /* Test isn't needed but avoids compiler warning */
      MALLOC_FAILURE_ACTION;
    }
  }
  else {
    size_t nb = request2size(bytes);
    size_t req = nb + alignment + MIN_CHUNK_SIZE - CHUNK_OVERHEAD;
    mem = internal_malloc(m, req);
    if (mem != 0) {
      mchunkptr p = mem2chunk(mem);
      if (PREACTION(m))
        return 0;
      if ((((size_t)(mem)) & (alignment - 1)) != 0) { /* misaligned */
        /*
          Find an aligned spot inside chunk.  Since we need to give
          back leading space in a chunk of at least MIN_CHUNK_SIZE, if
          the first calculation places us at a spot with less than
          MIN_CHUNK_SIZE leader, we can move to the next aligned spot.
          We've allocated enough total room so that this is always
          possible.
        */
        char* br = (char*)mem2chunk((size_t)(((size_t)((char*)mem + alignment -
                                                       SIZE_T_ONE)) &
                                             -alignment));
        char* pos = ((size_t)(br - (char*)(p)) >= MIN_CHUNK_SIZE)?
          br : br+alignment;
        mchunkptr newp = (mchunkptr)pos;
        size_t leadsize = pos - (char*)(p);
        size_t newsize = chunksize(p) - leadsize;

        if (is_mmapped(p)) { /* For mmapped chunks, just adjust offset */
          newp->prev_foot = p->prev_foot + leadsize;
          newp->head = newsize;
        }
        else { /* Otherwise, give back leader, use the rest */
          set_inuse(m, newp, newsize);
          set_inuse(m, p, leadsize);
          dispose_chunk(m, p, leadsize);
        }
        p = newp;
      }

      /* Give back spare room at the end */
      if (!is_mmapped(p)) {
        size_t size = chunksize(p);
        if (size > nb + MIN_CHUNK_SIZE) {
          size_t remainder_size = size - nb;
          mchunkptr remainder = chunk_plus_offset(p, nb);
          set_inuse(m, p, nb);
          set_inuse(m, remainder, remainder_size);
          dispose_chunk(m, remainder, remainder_size);
        }
      }

      mem = chunk2mem(p);
      assert (chunksize(p) >= nb);
      assert(((size_t)mem & (alignment - 1)) == 0);
      check_inuse_chunk(m, p);
      POSTACTION(m);
    }
  }
  return mem;
}

/*
  Common support for independent_X routines, handling
    all of the combinations that can result.
  The opts arg has:
    bit 0 set if all elements are same size (using sizes[0])
    bit 1 set if elements should be zeroed
*/
static void** ialloc(mstate m,
                     size_t n_elements,
                     size_t* sizes,
                     int opts,
                     void* chunks[]) {

  size_t    element_size;   /* chunksize of each element, if all same */
  size_t    contents_size;  /* total size of elements */
  size_t    array_size;     /* request size of pointer array */
  void*     mem;            /* malloced aggregate space */
  mchunkptr p;              /* corresponding chunk */
  size_t    remainder_size; /* remaining bytes while splitting */
  void**    marray;         /* either "chunks" or malloced ptr array */
  mchunkptr array_chunk;    /* chunk for malloced ptr array */
  flag_t    was_enabled;    /* to disable mmap */
  size_t    size;
  size_t    i;

  ensure_initialization();
  /* compute array length, if needed */
  if (chunks != 0) {
    if (n_elements == 0)
      return chunks; /* nothing to do */
    marray = chunks;
    array_size = 0;
  }
  else {
    /* if empty req, must still return chunk representing empty array */
    if (n_elements == 0)
      return (void**)internal_malloc(m, 0);
    marray = 0;
    array_size = request2size(n_elements * (sizeof(void*)));
  }

  /* compute total element size */
  if (opts & 0x1) { /* all-same-size */
    element_size = request2size(*sizes);
    contents_size = n_elements * element_size;
  }
  else { /* add up all the sizes */
    element_size = 0;
    contents_size = 0;
    for (i = 0; i != n_elements; ++i)
      contents_size += request2size(sizes[i]);
  }

  size = contents_size + array_size;

  /*
     Allocate the aggregate chunk.  First disable direct-mmapping so
     malloc won't use it, since we would not be able to later
     free/realloc space internal to a segregated mmap region.
  */
  was_enabled = use_mmap(m);
  disable_mmap(m);
  mem = internal_malloc(m, size - CHUNK_OVERHEAD);
  if (was_enabled)
    enable_mmap(m);
  if (mem == 0)
    return 0;

  if (PREACTION(m)) return 0;
  p = mem2chunk(mem);
  remainder_size = chunksize(p);

  assert(!is_mmapped(p));

  if (opts & 0x2) {       /* optionally clear the elements */
    memset((size_t*)mem, 0, remainder_size - SIZE_T_SIZE - array_size);
  }

  /* If not provided, allocate the pointer array as final part of chunk */
  if (marray == 0) {
    size_t  array_chunk_size;
    array_chunk = chunk_plus_offset(p, contents_size);
    array_chunk_size = remainder_size - contents_size;
    marray = (void**) (chunk2mem(array_chunk));
    set_size_and_pinuse_of_inuse_chunk(m, array_chunk, array_chunk_size);
    remainder_size = contents_size;
  }

  /* split out elements */
  for (i = 0; ; ++i) {
    marray[i] = chunk2mem(p);
    if (i != n_elements-1) {
      if (element_size != 0)
        size = element_size;
      else
        size = request2size(sizes[i]);
      remainder_size -= size;
      set_size_and_pinuse_of_inuse_chunk(m, p, size);
      p = chunk_plus_offset(p, size);
    }
    else { /* the final element absorbs any overallocation slop */
      set_size_and_pinuse_of_inuse_chunk(m, p, remainder_size);
      break;
    }
  }

#if DEBUG
  if (marray != chunks) {
    /* final element must have exactly exhausted chunk */
    if (element_size != 0) {
      assert(remainder_size == element_size);
    }
    else {
      assert(remainder_size == request2size(sizes[i]));
    }
    check_inuse_chunk(m, mem2chunk(marray));
  }
  for (i = 0; i != n_elements; ++i)
    check_inuse_chunk(m, mem2chunk(marray[i]));

#endif /* DEBUG */

  POSTACTION(m);
  return marray;
}

/* Try to free all pointers in the given array.
   Note: this could be made faster, by delaying consolidation,
   at the price of disabling some user integrity checks, We
   still optimize some consolidations by combining adjacent
   chunks before freeing, which will occur often if allocated
   with ialloc or the array is sorted.
*/
static size_t internal_bulk_free(mstate m, void* array[], size_t nelem) {
  size_t unfreed = 0;
  if (!PREACTION(m)) {
    void** a;
    void** fence = &(array[nelem]);
    for (a = array; a != fence; ++a) {
      void* mem = *a;
      if (mem != 0) {
        mchunkptr p = mem2chunk(mem);
        size_t psize = chunksize(p);
#if FOOTERS
        if (get_mstate_for(p) != m) {
          ++unfreed;
          continue;
        }
#endif
        check_inuse_chunk(m, p);
        *a = 0;
        if (RTCHECK(ok_address(m, p) && ok_inuse(p))) {
          void ** b = a + 1; /* try to merge with next chunk */
          mchunkptr next = next_chunk(p);
          if (b != fence && *b == chunk2mem(next)) {
            size_t newsize = chunksize(next) + psize;
            set_inuse(m, p, newsize);
            *b = chunk2mem(p);
          }
          else
            dispose_chunk(m, p, psize);
        }
        else {
          CORRUPTION_ERROR_ACTION(m);
          break;
        }
      }
    }
    if (should_trim(m, m->topsize))
      sys_trim(m, 0);
    POSTACTION(m);
  }
  return unfreed;
}

/* Traversal */
#if MALLOC_INSPECT_ALL
static void internal_inspect_all(mstate m,
                                 void(*handler)(void *start,
                                                void *end,
                                                size_t used_bytes,
                                                void* callback_arg),
                                 void* arg) {
  if (is_initialized(m)) {
    mchunkptr top = m->top;
    msegmentptr s;
    for (s = &m->seg; s != 0; s = s->next) {
      mchunkptr q = align_as_chunk(s->base);
      while (segment_holds(s, q) && q->head != FENCEPOST_HEAD) {
        mchunkptr next = next_chunk(q);
        size_t sz = chunksize(q);
        size_t used;
        void* start;
        if (is_inuse(q)) {
          used = sz - CHUNK_OVERHEAD; /* must not be mmapped */
          start = chunk2mem(q);
        }
        else {
          used = 0;
          if (is_small(sz)) {     /* offset by possible bookkeeping */
            start = (void*)((char*)q + sizeof(struct malloc_chunk));
          }
          else {
            start = (void*)((char*)q + sizeof(struct malloc_tree_chunk));
          }
        }
        if (start < (void*)next)  /* skip if all space is bookkeeping */
          handler(start, next, used, arg);
        if (q == top)
          break;
        q = next;
      }
    }
  }
}
#endif /* MALLOC_INSPECT_ALL */

/* ------------------ Exported realloc, memalign, etc -------------------- */

#if !ONLY_MSPACES

void* dlrealloc(void* oldmem, size_t bytes) {
  void* mem = 0;
  if (oldmem == 0) {
    mem = dlmalloc(bytes);
  }
  else if (bytes >= MAX_REQUEST) {
    MALLOC_FAILURE_ACTION;
  }
#ifdef REALLOC_ZERO_BYTES_FREES
  else if (bytes == 0) {
    dlfree(oldmem);
  }
#endif /* REALLOC_ZERO_BYTES_FREES */
  else {
    size_t nb = request2size(bytes);
    mchunkptr oldp = mem2chunk(oldmem);
#if ! FOOTERS
    mstate m = gm;
#else /* FOOTERS */
    mstate m = get_mstate_for(oldp);
    if (!ok_magic(m)) {
      USAGE_ERROR_ACTION(m, oldmem);
      return 0;
    }
#endif /* FOOTERS */
    if (!PREACTION(m)) {
      mchunkptr newp = try_realloc_chunk(m, oldp, nb, 1);
      POSTACTION(m);
      if (newp != 0) {
        check_inuse_chunk(m, newp);
        mem = chunk2mem(newp);
      }
      else {
        mem = internal_malloc(m, bytes);
        if (mem != 0) {
          size_t oc = chunksize(oldp) - overhead_for(oldp);
          memcpy(mem, oldmem, (oc < bytes)? oc : bytes);
          internal_free(m, oldmem);
        }
      }
    }
  }
  return mem;
}

void* dlrealloc_in_place(void* oldmem, size_t bytes) {
  void* mem = 0;
  if (oldmem != 0) {
    if (bytes >= MAX_REQUEST) {
      MALLOC_FAILURE_ACTION;
    }
    else {
      size_t nb = request2size(bytes);
      mchunkptr oldp = mem2chunk(oldmem);
#if ! FOOTERS
      mstate m = gm;
#else /* FOOTERS */
      mstate m = get_mstate_for(oldp);
      if (!ok_magic(m)) {
        USAGE_ERROR_ACTION(m, oldmem);
        return 0;
      }
#endif /* FOOTERS */
      if (!PREACTION(m)) {
        mchunkptr newp = try_realloc_chunk(m, oldp, nb, 0);
        POSTACTION(m);
        if (newp == oldp) {
          check_inuse_chunk(m, newp);
          mem = oldmem;
        }
      }
    }
  }
  return mem;
}

void* dlmemalign(size_t alignment, size_t bytes) {
  if (alignment <= MALLOC_ALIGNMENT) {
    return dlmalloc(bytes);
  }
  return internal_memalign(gm, alignment, bytes);
}

int dlposix_memalign(void** pp, size_t alignment, size_t bytes) {
  void* mem = 0;
  if (alignment == MALLOC_ALIGNMENT)
    mem = dlmalloc(bytes);
  else {
    size_t d = alignment / sizeof(void*);
    size_t r = alignment % sizeof(void*);
    if (r != 0 || d == 0 || (d & (d-SIZE_T_ONE)) != 0)
      return EINVAL;
    else if (bytes <= MAX_REQUEST - alignment) {
      if (alignment <  MIN_CHUNK_SIZE)
        alignment = MIN_CHUNK_SIZE;
      mem = internal_memalign(gm, alignment, bytes);
    }
  }
  if (mem == 0)
    return ENOMEM;
  else {
    *pp = mem;
    return 0;
  }
}

void* dlvalloc(size_t bytes) {
  size_t pagesz;
  ensure_initialization();
  pagesz = mparams.page_size;
  return dlmemalign(pagesz, bytes);
}

void* dlpvalloc(size_t bytes) {
  size_t pagesz;
  ensure_initialization();
  pagesz = mparams.page_size;
  return dlmemalign(pagesz, (bytes + pagesz - SIZE_T_ONE) & ~(pagesz - SIZE_T_ONE));
}

void** dlindependent_calloc(size_t n_elements, size_t elem_size,
                            void* chunks[]) {
  size_t sz = elem_size; /* serves as 1-element array */
  return ialloc(gm, n_elements, &sz, 3, chunks);
}

void** dlindependent_comalloc(size_t n_elements, size_t sizes[],
                              void* chunks[]) {
  return ialloc(gm, n_elements, sizes, 0, chunks);
}

size_t dlbulk_free(void* array[], size_t nelem) {
  return internal_bulk_free(gm, array, nelem);
}

#if MALLOC_INSPECT_ALL
void dlmalloc_inspect_all(void(*handler)(void *start,
                                         void *end,
                                         size_t used_bytes,
                                         void* callback_arg),
                          void* arg) {
  ensure_initialization();
  if (!PREACTION(gm)) {
    internal_inspect_all(gm, handler, arg);
    POSTACTION(gm);
  }
}
#endif /* MALLOC_INSPECT_ALL */

int dlmalloc_trim(size_t pad) {
  int result = 0;
  ensure_initialization();
  if (!PREACTION(gm)) {
    result = sys_trim(gm, pad);
    POSTACTION(gm);
  }
  return result;
}

size_t dlmalloc_footprint(void) {
  return gm->footprint;
}

size_t dlmalloc_max_footprint(void) {
  return gm->max_footprint;
}

size_t dlmalloc_footprint_limit(void) {
  size_t maf = gm->footprint_limit;
  return maf == 0 ? MAX_SIZE_T : maf;
}

size_t dlmalloc_set_footprint_limit(size_t bytes) {
  size_t result;  /* invert sense of 0 */
  if (bytes == 0)
    result = granularity_align(1); /* Use minimal size */
  if (bytes == MAX_SIZE_T)
    result = 0;                    /* disable */
  else
    result = granularity_align(bytes);
  return gm->footprint_limit = result;
}

#if !NO_MALLINFO
struct dlmallinfo dlmallinfo(void) {
  return internal_mallinfo(gm);
}
#endif /* NO_MALLINFO */

#if !NO_MALLOC_STATS
void dlmalloc_stats() {
  internal_malloc_stats(gm);
}
#endif /* NO_MALLOC_STATS */

int dlmallopt(int param_number, int value) {
  return change_mparam(param_number, value);
}

size_t dlmalloc_usable_size(void* mem) {
  if (mem != 0) {
    mchunkptr p = mem2chunk(mem);
    if (is_inuse(p))
      return chunksize(p) - overhead_for(p);
  }
  return 0;
}

#endif /* !ONLY_MSPACES */

/* ----------------------------- user mspaces ---------------------------- */

#if MSPACES

static mstate init_user_mstate(char* tbase, size_t tsize) {
  size_t msize = pad_request(sizeof(struct malloc_state));
  mchunkptr mn;
  mchunkptr msp = align_as_chunk(tbase);
  mstate m = (mstate)(chunk2mem(msp));
  memset(m, 0, msize);
  (void)INITIAL_LOCK(&m->mutex);
  msp->head = (msize|INUSE_BITS);
  m->seg.base = m->least_addr = tbase;
  m->seg.size = m->footprint = m->max_footprint = tsize;
  m->magic = mparams.magic;
  m->release_checks = MAX_RELEASE_CHECK_RATE;
  m->mflags = mparams.default_mflags;
  m->extp = 0;
  m->exts = 0;
  disable_contiguous(m);
  init_bins(m);
  mn = next_chunk(mem2chunk(m));
  init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) - TOP_FOOT_SIZE);
  check_top_chunk(m, m->top);
  return m;
}

mspace create_mspace(size_t capacity, int locked) {
  mstate m = 0;
  size_t msize;
  ensure_initialization();
  msize = pad_request(sizeof(struct malloc_state));
  if (capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
    size_t rs = ((capacity == 0)? mparams.granularity :
                 (capacity + TOP_FOOT_SIZE + msize));
    size_t tsize = granularity_align(rs);
    char* tbase = (char*)(CALL_MMAP(tsize));
    if (tbase != CMFAIL) {
      m = init_user_mstate(tbase, tsize);
      m->seg.sflags = USE_MMAP_BIT;
      set_lock(m, locked);
    }
  }
  return (mspace)m;
}

mspace create_mspace_with_base(void* base, size_t capacity, int locked) {
  mstate m = 0;
  size_t msize;
  ensure_initialization();
  msize = pad_request(sizeof(struct malloc_state));
  if (capacity > msize + TOP_FOOT_SIZE &&
      capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
    m = init_user_mstate((char*)base, capacity);
    m->seg.sflags = EXTERN_BIT;
    set_lock(m, locked);
  }
  return (mspace)m;
}

int mspace_track_large_chunks(mspace msp, int enable) {
  int ret = 0;
  mstate ms = (mstate)msp;
  if (!PREACTION(ms)) {
    if (!use_mmap(ms)) {
      ret = 1;
    }
    if (!enable) {
      enable_mmap(ms);
    } else {
      disable_mmap(ms);
    }
    POSTACTION(ms);
  }
  return ret;
}

CLIB_NOSANITIZE_ADDR
size_t destroy_mspace(mspace msp) {
  size_t freed = 0;
  mstate ms = (mstate)msp;
  if (ok_magic(ms)) {
    msegmentptr sp = &ms->seg;
    (void)DESTROY_LOCK(&ms->mutex); /* destroy before unmapped */
    while (sp != 0) {
      char* base = sp->base;
      size_t size = sp->size;
      flag_t flag = sp->sflags;
      (void)base; /* placate people compiling -Wunused-variable */
      sp = sp->next;
      if ((flag & USE_MMAP_BIT) && !(flag & EXTERN_BIT) &&
          CALL_MUNMAP(base, size) == 0)
        freed += size;
    }
  }
  else {
    USAGE_ERROR_ACTION(ms,ms);
  }
  return freed;
}

void mspace_get_address_and_size (mspace msp, char **addrp, size_t *sizep)
{
  mstate ms;
  msegment *this_seg;

  ms = (mstate)msp;
  this_seg = &ms->seg;

  *addrp = this_seg->base;
  *sizep = this_seg->size;
}

CLIB_NOSANITIZE_ADDR
int mspace_is_heap_object (mspace msp, void *p)
{
  msegment *this_seg;
  char *pp, *base;
  mstate ms;

  ms = (mstate)msp;

  this_seg = &ms->seg;
  pp = (char *) p;

  while (this_seg)
    {
      base = this_seg->base;
      if (pp >= base && pp < (base + this_seg->size))
        return 1;
      this_seg = this_seg->next;
    }

  if (pp > ms->least_addr && pp <= ms->least_addr + ms->footprint)
    return 1;

  return 0;
}

CLIB_NOSANITIZE_ADDR
void *mspace_least_addr (mspace msp)
{
  mstate ms = (mstate) msp;
  return (void *) ms->least_addr;
}

void mspace_disable_expand (mspace msp)
{
  mstate ms = (mstate)msp;

  disable_expand (ms);
}

CLIB_NOSANITIZE_ADDR
int mspace_enable_disable_trace (mspace msp, int enable)
{
  mstate ms = (mstate)msp;
  int was_enabled = 0;

  if (use_trace(ms))
    was_enabled = 1;

  if (enable)
    enable_trace (ms);
  else
    disable_trace (ms);

  return (was_enabled);
}

CLIB_NOSANITIZE_ADDR
int mspace_is_traced (mspace msp)
{
  mstate ms = (mstate)msp;

  if (use_trace(ms))
    return 1;
  return 0;
}

CLIB_NOSANITIZE_ADDR
void* mspace_get_aligned (mspace msp,
                          unsigned long n_user_data_bytes,
                          unsigned long align,
                          unsigned long align_offset) {
  char *rv;
  unsigned long searchp;
  unsigned *wwp;                /* "where's Waldo" pointer */
  mstate ms = (mstate)msp;

  /*
   * Allocate space for the "Where's Waldo?" pointer
   * the base of the dlmalloc object
   */
  n_user_data_bytes += sizeof(unsigned);

  /*
   * Alignment requests less than the size of an mmx vector are ignored
   */
  if (align < sizeof (uword)) {
    rv = mspace_malloc (msp, n_user_data_bytes);
    if (rv == 0)
        return rv;

    if (use_trace(ms)) {
      mchunkptr p  = mem2chunk(rv);
      size_t psize = chunksize(p);

      mheap_get_trace ((unsigned long)rv + sizeof (unsigned), psize);
    }

    wwp = (unsigned *)rv;
    *wwp = 0;
    rv += sizeof (unsigned);

    return rv;
  }

  /*
   * Alignment requests greater than 4K must be at offset zero,
   * and must be freed using mspace_free_no_offset - or never freed -
   * since the "Where's Waldo?" pointer would waste too much space.
   *
   * Waldo is the address of the chunk of memory returned by mspace_malloc,
   * which we need later to call mspace_free...
   */
  if (align > 4<<10 || align_offset == ~0UL) {
    n_user_data_bytes -= sizeof(unsigned);
    assert(align_offset == 0);
    rv = internal_memalign(ms, (size_t)align, n_user_data_bytes);

    /* Trace the allocation */
    if (rv && use_trace(ms)) {
      mchunkptr p  = mem2chunk(rv);
      size_t psize = chunksize(p);
      mheap_get_trace ((unsigned long)rv, psize);
    }
    return rv;
  }

  align = clib_max (align, MALLOC_ALIGNMENT);
  align = max_pow2 (align);

  /* Correct align offset to be smaller than alignment. */
  align_offset &= (align - 1);

  n_user_data_bytes += align;
  rv = mspace_malloc (msp, n_user_data_bytes);

  if (rv == 0)
      return rv;

  /* Honor the alignment request */
  searchp = (unsigned long)(rv + sizeof (unsigned));

#if 0  /* this is the idea... */
  while ((searchp + align_offset) % align)
    searchp++;
#endif

  {
    unsigned long where_now, delta;

    where_now = (searchp + align_offset) % align;
    delta = align - where_now;

    searchp += delta;
  }

  wwp = (unsigned *)(searchp - sizeof(unsigned));
  *wwp = (searchp - (((unsigned long) rv) + sizeof (*wwp)));
  assert (*wwp < align);

  if (use_trace(ms)) {
    mchunkptr p  = mem2chunk(rv);
    size_t psize = chunksize(p);
    mheap_get_trace (searchp, psize);
  }
  return (void *) searchp;
}

CLIB_NOSANITIZE_ADDR
void mspace_put (mspace msp, void *p_arg)
{
  char *object_header;
  unsigned *wwp;
  mstate ms = (mstate)msp;

  /* Find the object header delta */
  wwp = (unsigned *)p_arg;
  wwp --;

  /* Recover the dlmalloc object pointer */
  object_header = (char *)wwp;
  object_header -= *wwp;

  /* Tracing (if enabled) */
  if (use_trace(ms))
    {
      mchunkptr p  = mem2chunk(object_header);
      size_t psize = chunksize(p);

      mheap_put_trace ((unsigned long)p_arg, psize);
    }

#if CLIB_DEBUG > 0 && !defined(CLIB_SANITIZE_ADDR)
  /* Poison the object */
  {
    size_t psize = mspace_usable_size (object_header);
    memset (object_header, 0x13, psize);
  }
#endif

  /* And free it... */
  mspace_free (msp, object_header);
}

void mspace_put_no_offset (mspace msp, void *p_arg)
{
  mstate ms = (mstate)msp;

  if (use_trace(ms))
    {
      mchunkptr p  = mem2chunk(p_arg);
      size_t psize = chunksize(p);

      mheap_put_trace ((unsigned long)p_arg, psize);
    }
  mspace_free (msp, p_arg);
}

CLIB_NOSANITIZE_ADDR
size_t mspace_usable_size_with_delta (const void *p)
{
  size_t usable_size;
  char *object_header;
  unsigned *wwp;

  /* Find the object header delta */
  wwp = (unsigned *)p;
  wwp --;

  /* Recover the dlmalloc object pointer */
  object_header = (char *)wwp;
  object_header -= *wwp;

  usable_size = mspace_usable_size (object_header);
  /* account for the offset and the size of the offset... */
  usable_size -= (*wwp + sizeof (*wwp));
  return usable_size;
}

/*
  mspace versions of routines are near-clones of the global
  versions. This is not so nice but better than the alternatives.
*/

CLIB_NOSANITIZE_ADDR
void* mspace_malloc(mspace msp, size_t bytes) {
  mstate ms = (mstate)msp;
  if (!ok_magic(ms)) {
    USAGE_ERROR_ACTION(ms,ms);
    return 0;
  }
  if (!PREACTION(ms)) {
    void* mem;
    size_t nb;
    if (bytes <= MAX_SMALL_REQUEST) {
      bindex_t idx;
      binmap_t smallbits;
      nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
      idx = small_index(nb);
      smallbits = ms->smallmap >> idx;

      if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
        mchunkptr b, p;
        idx += ~smallbits & 1;       /* Uses next bin if idx empty */
        b = smallbin_at(ms, idx);
        p = b->fd;
        assert(chunksize(p) == small_index2size(idx));
        unlink_first_small_chunk(ms, b, p, idx);
        set_inuse_and_pinuse(ms, p, small_index2size(idx));
        mem = chunk2mem(p);
        check_malloced_chunk(ms, mem, nb);
        goto postaction;
      }

      else if (nb > ms->dvsize) {
        if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
          mchunkptr b, p, r;
          size_t rsize;
          bindex_t i;
          binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
          binmap_t leastbit = least_bit(leftbits);
          compute_bit2idx(leastbit, i);
          b = smallbin_at(ms, i);
          p = b->fd;
          assert(chunksize(p) == small_index2size(i));
          unlink_first_small_chunk(ms, b, p, i);
          rsize = small_index2size(i) - nb;
          /* Fit here cannot be remainderless if 4byte sizes */
          if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
            set_inuse_and_pinuse(ms, p, small_index2size(i));
          else {
            set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
            r = chunk_plus_offset(p, nb);
            set_size_and_pinuse_of_free_chunk(r, rsize);
            replace_dv(ms, r, rsize);
          }
          mem = chunk2mem(p);
          check_malloced_chunk(ms, mem, nb);
          goto postaction;
        }

        else if (ms->treemap != 0 && (mem = tmalloc_small(ms, nb)) != 0) {
          check_malloced_chunk(ms, mem, nb);
          goto postaction;
        }
      }
    }
    else if (bytes >= MAX_REQUEST)
      nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
    else {
      nb = pad_request(bytes);
      if (ms->treemap != 0 && (mem = tmalloc_large(ms, nb)) != 0) {
        check_malloced_chunk(ms, mem, nb);
        goto postaction;
      }
    }

    if (nb <= ms->dvsize) {
      size_t rsize = ms->dvsize - nb;
      mchunkptr p = ms->dv;
      if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
        mchunkptr r = ms->dv = chunk_plus_offset(p, nb);
        ms->dvsize = rsize;
        set_size_and_pinuse_of_free_chunk(r, rsize);
        set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
      }
      else { /* exhaust dv */
        size_t dvs = ms->dvsize;
        ms->dvsize = 0;
        ms->dv = 0;
        set_inuse_and_pinuse(ms, p, dvs);
      }
      mem = chunk2mem(p);
      check_malloced_chunk(ms, mem, nb);
      goto postaction;
    }

    else if (nb < ms->topsize) { /* Split top */
      size_t rsize = ms->topsize -= nb;
      mchunkptr p = ms->top;
      mchunkptr r = ms->top = chunk_plus_offset(p, nb);
      r->head = rsize | PINUSE_BIT;
      set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
      mem = chunk2mem(p);
      check_top_chunk(ms, ms->top);
      check_malloced_chunk(ms, mem, nb);
      goto postaction;
    }

    mem = sys_alloc(ms, nb);

  postaction:
    POSTACTION(ms);
    return mem;
  }

  return 0;
}

CLIB_NOSANITIZE_ADDR
void mspace_free(mspace msp, void* mem) {
  if (mem != 0) {
    mchunkptr p  = mem2chunk(mem);
#if FOOTERS
    mstate fm = get_mstate_for(p);
    (void)msp; /* placate people compiling -Wunused */
#else /* FOOTERS */
    mstate fm = (mstate)msp;
#endif /* FOOTERS */
    if (!ok_magic(fm)) {
      USAGE_ERROR_ACTION(fm, p);
      return;
    }
    if (!PREACTION(fm)) {
      check_inuse_chunk(fm, p);
      if (RTCHECK(ok_address(fm, p) && ok_inuse(p))) {
        size_t psize = chunksize(p);
        mchunkptr next = chunk_plus_offset(p, psize);
        if (!pinuse(p)) {
          size_t prevsize = p->prev_foot;
          if (is_mmapped(p)) {
            psize += prevsize + MMAP_FOOT_PAD;
            if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
              fm->footprint -= psize;
            goto postaction;
          }
          else {
            mchunkptr prev = chunk_minus_offset(p, prevsize);
            psize += prevsize;
            p = prev;
            if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
              if (p != fm->dv) {
                unlink_chunk(fm, p, prevsize);
              }
              else if ((next->head & INUSE_BITS) == INUSE_BITS) {
                fm->dvsize = psize;
                set_free_with_pinuse(p, psize, next);
                goto postaction;
              }
            }
            else
              goto erroraction;
          }
        }

        if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
          if (!cinuse(next)) {  /* consolidate forward */
            if (next == fm->top) {
              size_t tsize = fm->topsize += psize;
              fm->top = p;
              p->head = tsize | PINUSE_BIT;
              if (p == fm->dv) {
                fm->dv = 0;
                fm->dvsize = 0;
              }
              if (should_trim(fm, tsize))
                sys_trim(fm, 0);
              goto postaction;
            }
            else if (next == fm->dv) {
              size_t dsize = fm->dvsize += psize;
              fm->dv = p;
              set_size_and_pinuse_of_free_chunk(p, dsize);
              goto postaction;
            }
            else {
              size_t nsize = chunksize(next);
              psize += nsize;
              unlink_chunk(fm, next, nsize);
              set_size_and_pinuse_of_free_chunk(p, psize);
              if (p == fm->dv) {
                fm->dvsize = psize;
                goto postaction;
              }
            }
          }
          else
            set_free_with_pinuse(p, psize, next);

          if (is_small(psize)) {
            insert_small_chunk(fm, p, psize);
            check_free_chunk(fm, p);
          }
          else {
            tchunkptr tp = (tchunkptr)p;
            insert_large_chunk(fm, tp, psize);
            check_free_chunk(fm, p);
            if (--fm->release_checks == 0)
              release_unused_segments(fm);
          }
          goto postaction;
        }
      }
    erroraction:
      USAGE_ERROR_ACTION(fm, p);
    postaction:
      POSTACTION(fm);
    }
  }
}

void* mspace_calloc(mspace msp, size_t n_elements, size_t elem_size) {
  void* mem;
  size_t req = 0;
  mstate ms = (mstate)msp;
  if (!ok_magic(ms)) {
    USAGE_ERROR_ACTION(ms,ms);
    return 0;
  }
  if (n_elements != 0) {
    req = n_elements * elem_size;
    if (((n_elements | elem_size) & ~(size_t)0xffff) &&
        (req / n_elements != elem_size))
      req = MAX_SIZE_T; /* force downstream failure on overflow */
  }
  mem = internal_malloc(ms, req);
  if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
    memset(mem, 0, req);
  return mem;
}

void* mspace_realloc(mspace msp, void* oldmem, size_t bytes) {
  void* mem = 0;
  if (oldmem == 0) {
    mem = mspace_malloc(msp, bytes);
  }
  else if (bytes >= MAX_REQUEST) {
    MALLOC_FAILURE_ACTION;
  }
#ifdef REALLOC_ZERO_BYTES_FREES
  else if (bytes == 0) {
    mspace_free(msp, oldmem);
  }
#endif /* REALLOC_ZERO_BYTES_FREES */
  else {
    size_t nb = request2size(bytes);
    mchunkptr oldp = mem2chunk(oldmem);
#if ! FOOTERS
    mstate m = (mstate)msp;
#else /* FOOTERS */
    mstate m = get_mstate_for(oldp);
    if (!ok_magic(m)) {
      USAGE_ERROR_ACTION(m, oldmem);
      return 0;
    }
#endif /* FOOTERS */
    if (!PREACTION(m)) {
      mchunkptr newp = try_realloc_chunk(m, oldp, nb, 1);
      POSTACTION(m);
      if (newp != 0) {
        check_inuse_chunk(m, newp);
        mem = chunk2mem(newp);
      }
      else {
        mem = mspace_malloc(m, bytes);
        if (mem != 0) {
          size_t oc = chunksize(oldp) - overhead_for(oldp);
          memcpy(mem, oldmem, (oc < bytes)? oc : bytes);
          mspace_free(m, oldmem);
        }
      }
    }
  }
  return mem;
}

void* mspace_realloc_in_place(mspace msp, void* oldmem, size_t bytes) {
  void* mem = 0;
  if (oldmem != 0) {
    if (bytes >= MAX_REQUEST) {
      MALLOC_FAILURE_ACTION;
    }
    else {
      size_t nb = request2size(bytes);
      mchunkptr oldp = mem2chunk(oldmem);
#if ! FOOTERS
      mstate m = (mstate)msp;
#else /* FOOTERS */
      mstate m = get_mstate_for(oldp);
      (void)msp; /* placate people compiling -Wunused */
      if (!ok_magic(m)) {
        USAGE_ERROR_ACTION(m, oldmem);
        return 0;
      }
#endif /* FOOTERS */
      if (!PREACTION(m)) {
        mchunkptr newp = try_realloc_chunk(m, oldp, nb, 0);
        POSTACTION(m);
        if (newp == oldp) {
          check_inuse_chunk(m, newp);
          mem = oldmem;
        }
      }
    }
  }
  return mem;
}

void* mspace_memalign(mspace msp, size_t alignment, size_t bytes) {
  mstate ms = (mstate)msp;
  if (!ok_magic(ms)) {
    USAGE_ERROR_ACTION(ms,ms);
    return 0;
  }
  if (alignment <= MALLOC_ALIGNMENT)
    return mspace_malloc(msp, bytes);
  return internal_memalign(ms, alignment, bytes);
}

void** mspace_independent_calloc(mspace msp, size_t n_elements,
                                 size_t elem_size, void* chunks[]) {
  size_t sz = elem_size; /* serves as 1-element array */
  mstate ms = (mstate)msp;
  if (!ok_magic(ms)) {
    USAGE_ERROR_ACTION(ms,ms);
    return 0;
  }
  return ialloc(ms, n_elements, &sz, 3, chunks);
}

void** mspace_independent_comalloc(mspace msp, size_t n_elements,
                                   size_t sizes[], void* chunks[]) {
  mstate ms = (mstate)msp;
  if (!ok_magic(ms)) {
    USAGE_ERROR_ACTION(ms,ms);
    return 0;
  }
  return ialloc(ms, n_elements, sizes, 0, chunks);
}

size_t mspace_bulk_free(mspace msp, void* array[], size_t nelem) {
  return internal_bulk_free((mstate)msp, array, nelem);
}

#if MALLOC_INSPECT_ALL
void mspace_inspect_all(mspace msp,
                        void(*handler)(void *start,
                                       void *end,
                                       size_t used_bytes,
                                       void* callback_arg),
                        void* arg) {
  mstate ms = (mstate)msp;
  if (ok_magic(ms)) {
    if (!PREACTION(ms)) {
      internal_inspect_all(ms, handler, arg);
      POSTACTION(ms);
    }
  }
  else {
    USAGE_ERROR_ACTION(ms,ms);
  }
}
#endif /* MALLOC_INSPECT_ALL */

int mspace_trim(mspace msp, size_t pad) {
  int result = 0;
  mstate ms = (mstate)msp;
  if (ok_magic(ms)) {
    if (!PREACTION(ms)) {
      result = sys_trim(ms, pad);
      POSTACTION(ms);
    }
  }
  else {
    USAGE_ERROR_ACTION(ms,ms);
  }
  return result;
}

#if !NO_MALLOC_STATS
void mspace_malloc_stats(mspace msp) {
  mstate ms = (mstate)msp;
  if (ok_magic(ms)) {
    internal_malloc_stats(ms);
  }
  else {
    USAGE_ERROR_ACTION(ms,ms);
  }
}
#endif /* NO_MALLOC_STATS */

size_t mspace_footprint(mspace msp) {
  size_t result = 0;
  mstate ms = (mstate)msp;
  if (ok_magic(ms)) {
    result = ms->footprint;
  }
  else {
    USAGE_ERROR_ACTION(ms,ms);
  }
  return result;
}

size_t mspace_max_footprint(mspace msp) {
  size_t result = 0;
  mstate ms = (mstate)msp;
  if (ok_magic(ms)) {
    result = ms->max_footprint;
  }
  else {
    USAGE_ERROR_ACTION(ms,ms);
  }
  return result;
}

size_t mspace_footprint_limit(mspace msp) {
  size_t result = 0;
  mstate ms = (mstate)msp;
  if (ok_magic(ms)) {
    size_t maf = ms->footprint_limit;
    result = (maf == 0) ? MAX_SIZE_T : maf;
  }
  else {
    USAGE_ERROR_ACTION(ms,ms);
  }
  return result;
}

size_t mspace_set_footprint_limit(mspace msp, size_t bytes) {
  size_t result = 0;
  mstate ms = (mstate)msp;
  if (ok_magic(ms)) {
    if (bytes == 0)
      result = granularity_align(1); /* Use minimal size */
    if (bytes == MAX_SIZE_T)
      result = 0;                    /* disable */
    else
      result = granularity_align(bytes);
    ms->footprint_limit = result;
  }
  else {
    USAGE_ERROR_ACTION(ms,ms);
  }
  return result;
}

#if !NO_MALLINFO
CLIB_NOSANITIZE_ADDR
struct dlmallinfo mspace_mallinfo(mspace msp) {
  mstate ms = (mstate)msp;
  if (!ok_magic(ms)) {
    USAGE_ERROR_ACTION(ms,ms);
  }
  return internal_mallinfo(ms);
}
#endif /* NO_MALLINFO */

CLIB_NOSANITIZE_ADDR
size_t mspace_usable_size(const void* mem) {
  if (mem != 0) {
    mchunkptr p = mem2chunk(mem);
    if (is_inuse(p))
      return chunksize(p) - overhead_for(p);
  }
  return 0;
}

int mspace_mallopt(int param_number, int value) {
  return change_mparam(param_number, value);
}

#endif /* MSPACES */


/* -------------------- Alternative MORECORE functions ------------------- */

/*
  Guidelines for creating a custom version of MORECORE:

  * For best performance, MORECORE should allocate in multiples of pagesize.
  * MORECORE may allocate more memory than requested. (Or even less,
      but this will usually result in a malloc failure.)
  * MORECORE must not allocate memory when given argument zero, but
      instead return one past the end address of memory from previous
      nonzero call.
  * For best performance, consecutive calls to MORECORE with positive
      arguments should return increasing addresses, indicating that
      space has been contiguously extended.
  * Even though consecutive calls to MORECORE need not return contiguous
      addresses, it must be OK for malloc'ed chunks to span multiple
      regions in those cases where they do happen to be contiguous.
  * MORECORE need not handle negative arguments -- it may instead
      just return MFAIL when given negative arguments.
      Negative arguments are always multiples of pagesize. MORECORE
      must not misinterpret negative args as large positive unsigned
      args. You can suppress all such calls from even occurring by defining
      MORECORE_CANNOT_TRIM,

  As an example alternative MORECORE, here is a custom allocator
  kindly contributed for pre-OSX macOS.  It uses virtually but not
  necessarily physically contiguous non-paged memory (locked in,
  present and won't get swapped out).  You can use it by uncommenting
  this section, adding some #includes, and setting up the appropriate
  defines above:

      #define MORECORE osMoreCore

  There is also a shutdown routine that should somehow be called for
  cleanup upon program exit.

  #define MAX_POOL_ENTRIES 100
  #define MINIMUM_MORECORE_SIZE  (64 * 1024U)
  static int next_os_pool;
  void *our_os_pools[MAX_POOL_ENTRIES];

  void *osMoreCore(int size)
  {
    void *ptr = 0;
    static void *sbrk_top = 0;

    if (size > 0)
    {
      if (size < MINIMUM_MORECORE_SIZE)
         size = MINIMUM_MORECORE_SIZE;
      if (CurrentExecutionLevel() == kTaskLevel)
         ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0);
      if (ptr == 0)
      {
        return (void *) MFAIL;
      }
      // save ptrs so they can be freed during cleanup
      our_os_pools[next_os_pool] = ptr;
      next_os_pool++;
      ptr = (void *) ((((size_t) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK);
      sbrk_top = (char *) ptr + size;
      return ptr;
    }
    else if (size < 0)
    {
      // we don't currently support shrink behavior
      return (void *) MFAIL;
    }
    else
    {
      return sbrk_top;
    }
  }

  // cleanup any allocated memory pools
  // called as last thing before shutting down driver

  void osCleanupMem(void)
  {
    void **ptr;

    for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++)
      if (*ptr)
      {
         PoolDeallocate(*ptr);
         *ptr = 0;
      }
  }

*/


/* -----------------------------------------------------------------------
History:
    v2.8.6 Wed Aug 29 06:57:58 2012  Doug Lea
      * fix bad comparison in dlposix_memalign
      * don't reuse adjusted asize in sys_alloc
      * add LOCK_AT_FORK -- thanks to Kirill Artamonov for the suggestion
      * reduce compiler warnings -- thanks to all who reported/suggested these

    v2.8.5 Sun May 22 10:26:02 2011  Doug Lea  (dl at gee)
      * Always perform unlink checks unless INSECURE
      * Add posix_memalign.
      * Improve realloc to expand in more cases; expose realloc_in_place.
        Thanks to Peter Buhr for the suggestion.
      * Add footprint_limit, inspect_all, bulk_free. Thanks
        to Barry Hayes and others for the suggestions.
      * Internal refactorings to avoid calls while holding locks
      * Use non-reentrant locks by default. Thanks to Roland McGrath
        for the suggestion.
      * Small fixes to mspace_destroy, reset_on_error.
      * Various configuration extensions/changes. Thanks
         to all who contributed these.

    V2.8.4a Thu Apr 28 14:39:43 2011 (dl at gee.cs.oswego.edu)
      * Update Creative Commons URL

    V2.8.4 Wed May 27 09:56:23 2009  Doug Lea  (dl at gee)
      * Use zeros instead of prev foot for is_mmapped
      * Add mspace_track_large_chunks; thanks to Jean Brouwers
      * Fix set_inuse in internal_realloc; thanks to Jean Brouwers
      * Fix insufficient sys_alloc padding when using 16byte alignment
      * Fix bad error check in mspace_footprint
      * Adaptations for ptmalloc; thanks to Wolfram Gloger.
      * Reentrant spin locks; thanks to Earl Chew and others
      * Win32 improvements; thanks to Niall Douglas and Earl Chew
      * Add NO_SEGMENT_TRAVERSAL and MAX_RELEASE_CHECK_RATE options
      * Extension hook in malloc_state
      * Various small adjustments to reduce warnings on some compilers
      * Various configuration extensions/changes for more platforms. Thanks
         to all who contributed these.

    V2.8.3 Thu Sep 22 11:16:32 2005  Doug Lea  (dl at gee)
      * Add max_footprint functions
      * Ensure all appropriate literals are size_t
      * Fix conditional compilation problem for some #define settings
      * Avoid concatenating segments with the one provided
        in create_mspace_with_base
      * Rename some variables to avoid compiler shadowing warnings
      * Use explicit lock initialization.
      * Better handling of sbrk interference.
      * Simplify and fix segment insertion, trimming and mspace_destroy
      * Reinstate REALLOC_ZERO_BYTES_FREES option from 2.7.x
      * Thanks especially to Dennis Flanagan for help on these.

    V2.8.2 Sun Jun 12 16:01:10 2005  Doug Lea  (dl at gee)
      * Fix memalign brace error.

    V2.8.1 Wed Jun  8 16:11:46 2005  Doug Lea  (dl at gee)
      * Fix improper #endif nesting in C++
      * Add explicit casts needed for C++

    V2.8.0 Mon May 30 14:09:02 2005  Doug Lea  (dl at gee)
      * Use trees for large bins
      * Support mspaces
      * Use segments to unify sbrk-based and mmap-based system allocation,
        removing need for emulation on most platforms without sbrk.
      * Default safety checks
      * Optional footer checks. Thanks to William Robertson for the idea.
      * Internal code refactoring
      * Incorporate suggestions and platform-specific changes.
        Thanks to Dennis Flanagan, Colin Plumb, Niall Douglas,
        Aaron Bachmann,  Emery Berger, and others.
      * Speed up non-fastbin processing enough to remove fastbins.
      * Remove useless cfree() to avoid conflicts with other apps.
      * Remove internal memcpy, memset. Compilers handle builtins better.
      * Remove some options that no one ever used and rename others.

    V2.7.2 Sat Aug 17 09:07:30 2002  Doug Lea  (dl at gee)
      * Fix malloc_state bitmap array misdeclaration

    V2.7.1 Thu Jul 25 10:58:03 2002  Doug Lea  (dl at gee)
      * Allow tuning of FIRST_SORTED_BIN_SIZE
      * Use PTR_UINT as type for all ptr->int casts. Thanks to John Belmonte.
      * Better detection and support for non-contiguousness of MORECORE.
        Thanks to Andreas Mueller, Conal Walsh, and Wolfram Gloger
      * Bypass most of malloc if no frees. Thanks To Emery Berger.
      * Fix freeing of old top non-contiguous chunk im sysmalloc.
      * Raised default trim and map thresholds to 256K.
      * Fix mmap-related #defines. Thanks to Lubos Lunak.
      * Fix copy macros; added LACKS_FCNTL_H. Thanks to Neal Walfield.
      * Branch-free bin calculation
      * Default trim and mmap thresholds now 256K.

    V2.7.0 Sun Mar 11 14:14:06 2001  Doug Lea  (dl at gee)
      * Introduce independent_comalloc and independent_calloc.
        Thanks to Michael Pachos for motivation and help.
      * Make optional .h file available
      * Allow > 2GB requests on 32bit systems.
      * new WIN32 sbrk, mmap, munmap, lock code from <Walter@GeNeSys-e.de>.
        Thanks also to Andreas Mueller <a.mueller at paradatec.de>,
        and Anonymous.
      * Allow override of MALLOC_ALIGNMENT (Thanks to Ruud Waij for
        helping test this.)
      * memalign: check alignment arg
      * realloc: don't try to shift chunks backwards, since this
        leads to  more fragmentation in some programs and doesn't
        seem to help in any others.
      * Collect all cases in malloc requiring system memory into sysmalloc
      * Use mmap as backup to sbrk
      * Place all internal state in malloc_state
      * Introduce fastbins (although similar to 2.5.1)
      * Many minor tunings and cosmetic improvements
      * Introduce USE_PUBLIC_MALLOC_WRAPPERS, USE_MALLOC_LOCK
      * Introduce MALLOC_FAILURE_ACTION, MORECORE_CONTIGUOUS
        Thanks to Tony E. Bennett <tbennett@nvidia.com> and others.
      * Include errno.h to support default failure action.

    V2.6.6 Sun Dec  5 07:42:19 1999  Doug Lea  (dl at gee)
      * return null for negative arguments
      * Added Several WIN32 cleanups from Martin C. Fong <mcfong at yahoo.com>
         * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h'
          (e.g. WIN32 platforms)
         * Cleanup header file inclusion for WIN32 platforms
         * Cleanup code to avoid Microsoft Visual C++ compiler complaints
         * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing
           memory allocation routines
         * Set 'malloc_getpagesize' for WIN32 platforms (needs more work)
         * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to
           usage of 'assert' in non-WIN32 code
         * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to
           avoid infinite loop
      * Always call 'fREe()' rather than 'free()'

    V2.6.5 Wed Jun 17 15:57:31 1998  Doug Lea  (dl at gee)
      * Fixed ordering problem with boundary-stamping

    V2.6.3 Sun May 19 08:17:58 1996  Doug Lea  (dl at gee)
      * Added pvalloc, as recommended by H.J. Liu
      * Added 64bit pointer support mainly from Wolfram Gloger
      * Added anonymously donated WIN32 sbrk emulation
      * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen
      * malloc_extend_top: fix mask error that caused wastage after
        foreign sbrks
      * Add linux mremap support code from HJ Liu

    V2.6.2 Tue Dec  5 06:52:55 1995  Doug Lea  (dl at gee)
      * Integrated most documentation with the code.
      * Add support for mmap, with help from
        Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
      * Use last_remainder in more cases.
      * Pack bins using idea from  colin@nyx10.cs.du.edu
      * Use ordered bins instead of best-fit threshold
      * Eliminate block-local decls to simplify tracing and debugging.
      * Support another case of realloc via move into top
      * Fix error occurring when initial sbrk_base not word-aligned.
      * Rely on page size for units instead of SBRK_UNIT to
        avoid surprises about sbrk alignment conventions.
      * Add mallinfo, mallopt. Thanks to Raymond Nijssen
        (raymond@es.ele.tue.nl) for the suggestion.
      * Add `pad' argument to malloc_trim and top_pad mallopt parameter.
      * More precautions for cases where other routines call sbrk,
        courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
      * Added macros etc., allowing use in linux libc from
        H.J. Lu (hjl@gnu.ai.mit.edu)
      * Inverted this history list

    V2.6.1 Sat Dec  2 14:10:57 1995  Doug Lea  (dl at gee)
      * Re-tuned and fixed to behave more nicely with V2.6.0 changes.
      * Removed all preallocation code since under current scheme
        the work required to undo bad preallocations exceeds
        the work saved in good cases for most test programs.
      * No longer use return list or unconsolidated bins since
        no scheme using them consistently outperforms those that don't
        given above changes.
      * Use best fit for very large chunks to prevent some worst-cases.
      * Added some support for debugging

    V2.6.0 Sat Nov  4 07:05:23 1995  Doug Lea  (dl at gee)
      * Removed footers when chunks are in use. Thanks to
        Paul Wilson (wilson@cs.texas.edu) for the suggestion.

    V2.5.4 Wed Nov  1 07:54:51 1995  Doug Lea  (dl at gee)
      * Added malloc_trim, with help from Wolfram Gloger
        (wmglo@Dent.MED.Uni-Muenchen.DE).

    V2.5.3 Tue Apr 26 10:16:01 1994  Doug Lea  (dl at g)

    V2.5.2 Tue Apr  5 16:20:40 1994  Doug Lea  (dl at g)
      * realloc: try to expand in both directions
      * malloc: swap order of clean-bin strategy;
      * realloc: only conditionally expand backwards
      * Try not to scavenge used bins
      * Use bin counts as a guide to preallocation
      * Occasionally bin return list chunks in first scan
      * Add a few optimizations from colin@nyx10.cs.du.edu

    V2.5.1 Sat Aug 14 15:40:43 1993  Doug Lea  (dl at g)
      * faster bin computation & slightly different binning
      * merged all consolidations to one part of malloc proper
         (eliminating old malloc_find_space & malloc_clean_bin)
      * Scan 2 returns chunks (not just 1)
      * Propagate failure in realloc if malloc returns 0
      * Add stuff to allow compilation on non-ANSI compilers
          from kpv@research.att.com

    V2.5 Sat Aug  7 07:41:59 1993  Doug Lea  (dl at g.oswego.edu)
      * removed potential for odd address access in prev_chunk
      * removed dependency on getpagesize.h
      * misc cosmetics and a bit more internal documentation
      * anticosmetics: mangled names in macros to evade debugger strangeness
      * tested on sparc, hp-700, dec-mips, rs6000
          with gcc & native cc (hp, dec only) allowing
          Detlefs & Zorn comparison study (in SIGPLAN Notices.)

    Trial version Fri Aug 28 13:14:29 1992  Doug Lea  (dl at g.oswego.edu)
      * Based loosely on libg++-1.2X malloc. (It retains some of the overall
         structure of old version,  but most details differ.)

*/