DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (1aeaa33a64f9)

VCS Links

Line Code
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
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

// Portions of this file were originally under the following license:
//
// Copyright (C) 2006-2008 Jason Evans <jasone@FreeBSD.org>.
// All rights reserved.
// Copyright (C) 2007-2017 Mozilla Foundation.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
//    notice(s), this list of conditions and the following disclaimer as
//    the first lines of this file unmodified other than the possible
//    addition of one or more copyright notices.
// 2. Redistributions in binary form must reproduce the above copyright
//    notice(s), this list of conditions and the following disclaimer in
//    the documentation and/or other materials provided with the
//    distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
// OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
// EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// *****************************************************************************
//
// This allocator implementation is designed to provide scalable performance
// for multi-threaded programs on multi-processor systems.  The following
// features are included for this purpose:
//
//   + Multiple arenas are used if there are multiple CPUs, which reduces lock
//     contention and cache sloshing.
//
//   + Cache line sharing between arenas is avoided for internal data
//     structures.
//
//   + Memory is managed in chunks and runs (chunks can be split into runs),
//     rather than as individual pages.  This provides a constant-time
//     mechanism for associating allocations with particular arenas.
//
// Allocation requests are rounded up to the nearest size class, and no record
// of the original request size is maintained.  Allocations are broken into
// categories according to size class.  Assuming runtime defaults, 4 kB pages
// and a 16 byte quantum on a 32-bit system, the size classes in each category
// are as follows:
//
//   |=====================================|
//   | Category | Subcategory    |    Size |
//   |=====================================|
//   | Small    | Tiny           |       4 |
//   |          |                |       8 |
//   |          |----------------+---------|
//   |          | Quantum-spaced |      16 |
//   |          |                |      32 |
//   |          |                |      48 |
//   |          |                |     ... |
//   |          |                |     480 |
//   |          |                |     496 |
//   |          |                |     512 |
//   |          |----------------+---------|
//   |          | Sub-page       |    1 kB |
//   |          |                |    2 kB |
//   |=====================================|
//   | Large                     |    4 kB |
//   |                           |    8 kB |
//   |                           |   12 kB |
//   |                           |     ... |
//   |                           | 1012 kB |
//   |                           | 1016 kB |
//   |                           | 1020 kB |
//   |=====================================|
//   | Huge                      |    1 MB |
//   |                           |    2 MB |
//   |                           |    3 MB |
//   |                           |     ... |
//   |=====================================|
//
// NOTE: Due to Mozilla bug 691003, we cannot reserve less than one word for an
// allocation on Linux or Mac.  So on 32-bit *nix, the smallest bucket size is
// 4 bytes, and on 64-bit, the smallest bucket size is 8 bytes.
//
// A different mechanism is used for each category:
//
//   Small : Each size class is segregated into its own set of runs.  Each run
//           maintains a bitmap of which regions are free/allocated.
//
//   Large : Each allocation is backed by a dedicated run.  Metadata are stored
//           in the associated arena chunk header maps.
//
//   Huge : Each allocation is backed by a dedicated contiguous set of chunks.
//          Metadata are stored in a separate red-black tree.
//
// *****************************************************************************

#include "mozmemory_wrap.h"
#include "mozjemalloc.h"
#include "mozjemalloc_types.h"

#include <cstring>
#include <cerrno>
#ifdef XP_WIN
#include <io.h>
#include <windows.h>
#else
#include <sys/mman.h>
#include <unistd.h>
#endif
#ifdef XP_DARWIN
#include <libkern/OSAtomic.h>
#include <mach/mach_init.h>
#include <mach/vm_map.h>
#endif

#include "mozilla/Atomics.h"
#include "mozilla/Alignment.h"
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/DoublyLinkedList.h"
#include "mozilla/Likely.h"
#include "mozilla/MathAlgorithms.h"
#include "mozilla/Sprintf.h"
// Note: MozTaggedAnonymousMmap() could call an LD_PRELOADed mmap
// instead of the one defined here; use only MozTagAnonymousMemory().
#include "mozilla/TaggedAnonymousMemory.h"
#include "mozilla/ThreadLocal.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/Unused.h"
#include "mozilla/fallible.h"
#include "rb.h"
#include "Mutex.h"
#include "Utils.h"

using namespace mozilla;

// On Linux, we use madvise(MADV_DONTNEED) to release memory back to the
// operating system.  If we release 1MB of live pages with MADV_DONTNEED, our
// RSS will decrease by 1MB (almost) immediately.
//
// On Mac, we use madvise(MADV_FREE).  Unlike MADV_DONTNEED on Linux, MADV_FREE
// on Mac doesn't cause the OS to release the specified pages immediately; the
// OS keeps them in our process until the machine comes under memory pressure.
//
// It's therefore difficult to measure the process's RSS on Mac, since, in the
// absence of memory pressure, the contribution from the heap to RSS will not
// decrease due to our madvise calls.
//
// We therefore define MALLOC_DOUBLE_PURGE on Mac.  This causes jemalloc to
// track which pages have been MADV_FREE'd.  You can then call
// jemalloc_purge_freed_pages(), which will force the OS to release those
// MADV_FREE'd pages, making the process's RSS reflect its true memory usage.
//
// The jemalloc_purge_freed_pages definition in memory/build/mozmemory.h needs
// to be adjusted if MALLOC_DOUBLE_PURGE is ever enabled on Linux.

#ifdef XP_DARWIN
#define MALLOC_DOUBLE_PURGE
#endif

#ifdef XP_WIN
#define MALLOC_DECOMMIT
#endif

// When MALLOC_STATIC_PAGESIZE is defined, the page size is fixed at
// compile-time for better performance, as opposed to determined at
// runtime. Some platforms can have different page sizes at runtime
// depending on kernel configuration, so they are opted out by default.
// Debug builds are opted out too, for test coverage.
#ifndef MOZ_DEBUG
#if !defined(__ia64__) && !defined(__sparc__) && !defined(__mips__) && \
    !defined(__aarch64__)
#define MALLOC_STATIC_PAGESIZE 1
#endif
#endif

#ifdef XP_WIN
#define STDERR_FILENO 2

// Implement getenv without using malloc.
static char mozillaMallocOptionsBuf[64];

#define getenv xgetenv
static char* getenv(const char* name) {
  if (GetEnvironmentVariableA(name, mozillaMallocOptionsBuf,
                              sizeof(mozillaMallocOptionsBuf)) > 0) {
    return mozillaMallocOptionsBuf;
  }

  return nullptr;
}
#endif

#ifndef XP_WIN
// Newer Linux systems support MADV_FREE, but we're not supporting
// that properly. bug #1406304.
#if defined(XP_LINUX) && defined(MADV_FREE)
#undef MADV_FREE
#endif
#ifndef MADV_FREE
#define MADV_FREE MADV_DONTNEED
#endif
#endif

// Some tools, such as /dev/dsp wrappers, LD_PRELOAD libraries that
// happen to override mmap() and call dlsym() from their overridden
// mmap(). The problem is that dlsym() calls malloc(), and this ends
// up in a dead lock in jemalloc.
// On these systems, we prefer to directly use the system call.
// We do that for Linux systems and kfreebsd with GNU userland.
// Note sanity checks are not done (alignment of offset, ...) because
// the uses of mmap are pretty limited, in jemalloc.
//
// On Alpha, glibc has a bug that prevents syscall() to work for system
// calls with 6 arguments.
#if (defined(XP_LINUX) && !defined(__alpha__)) || \
    (defined(__FreeBSD_kernel__) && defined(__GLIBC__))
#include <sys/syscall.h>
#if defined(SYS_mmap) || defined(SYS_mmap2)
static inline void* _mmap(void* addr, size_t length, int prot, int flags,
                          int fd, off_t offset) {
// S390 only passes one argument to the mmap system call, which is a
// pointer to a structure containing the arguments.
#ifdef __s390__
  struct {
    void* addr;
    size_t length;
    long prot;
    long flags;
    long fd;
    off_t offset;
  } args = {addr, length, prot, flags, fd, offset};
  return (void*)syscall(SYS_mmap, &args);
#else
#if defined(ANDROID) && defined(__aarch64__) && defined(SYS_mmap2)
// Android NDK defines SYS_mmap2 for AArch64 despite it not supporting mmap2.
#undef SYS_mmap2
#endif
#ifdef SYS_mmap2
  return (void*)syscall(SYS_mmap2, addr, length, prot, flags, fd, offset >> 12);
#else
  return (void*)syscall(SYS_mmap, addr, length, prot, flags, fd, offset);
#endif
#endif
}
#define mmap _mmap
#define munmap(a, l) syscall(SYS_munmap, a, l)
#endif
#endif

// ***************************************************************************
// Structures for chunk headers for chunks used for non-huge allocations.

struct arena_t;

// Each element of the chunk map corresponds to one page within the chunk.
struct arena_chunk_map_t {
  // Linkage for run trees.  There are two disjoint uses:
  //
  // 1) arena_t's tree or available runs.
  // 2) arena_run_t conceptually uses this linkage for in-use non-full
  //    runs, rather than directly embedding linkage.
  RedBlackTreeNode<arena_chunk_map_t> link;

  // Run address (or size) and various flags are stored together.  The bit
  // layout looks like (assuming 32-bit system):
  //
  //   ???????? ???????? ????---- -mckdzla
  //
  // ? : Unallocated: Run address for first/last pages, unset for internal
  //                  pages.
  //     Small: Run address.
  //     Large: Run size for first page, unset for trailing pages.
  // - : Unused.
  // m : MADV_FREE/MADV_DONTNEED'ed?
  // c : decommitted?
  // k : key?
  // d : dirty?
  // z : zeroed?
  // l : large?
  // a : allocated?
  //
  // Following are example bit patterns for the three types of runs.
  //
  // r : run address
  // s : run size
  // x : don't care
  // - : 0
  // [cdzla] : bit set
  //
  //   Unallocated:
  //     ssssssss ssssssss ssss---- --c-----
  //     xxxxxxxx xxxxxxxx xxxx---- ----d---
  //     ssssssss ssssssss ssss---- -----z--
  //
  //   Small:
  //     rrrrrrrr rrrrrrrr rrrr---- -------a
  //     rrrrrrrr rrrrrrrr rrrr---- -------a
  //     rrrrrrrr rrrrrrrr rrrr---- -------a
  //
  //   Large:
  //     ssssssss ssssssss ssss---- ------la
  //     -------- -------- -------- ------la
  //     -------- -------- -------- ------la
  size_t bits;

// Note that CHUNK_MAP_DECOMMITTED's meaning varies depending on whether
// MALLOC_DECOMMIT and MALLOC_DOUBLE_PURGE are defined.
//
// If MALLOC_DECOMMIT is defined, a page which is CHUNK_MAP_DECOMMITTED must be
// re-committed with pages_commit() before it may be touched.  If
// MALLOC_DECOMMIT is defined, MALLOC_DOUBLE_PURGE may not be defined.
//
// If neither MALLOC_DECOMMIT nor MALLOC_DOUBLE_PURGE is defined, pages which
// are madvised (with either MADV_DONTNEED or MADV_FREE) are marked with
// CHUNK_MAP_MADVISED.
//
// Otherwise, if MALLOC_DECOMMIT is not defined and MALLOC_DOUBLE_PURGE is
// defined, then a page which is madvised is marked as CHUNK_MAP_MADVISED.
// When it's finally freed with jemalloc_purge_freed_pages, the page is marked
// as CHUNK_MAP_DECOMMITTED.
#define CHUNK_MAP_MADVISED ((size_t)0x40U)
#define CHUNK_MAP_DECOMMITTED ((size_t)0x20U)
#define CHUNK_MAP_MADVISED_OR_DECOMMITTED \
  (CHUNK_MAP_MADVISED | CHUNK_MAP_DECOMMITTED)
#define CHUNK_MAP_KEY ((size_t)0x10U)
#define CHUNK_MAP_DIRTY ((size_t)0x08U)
#define CHUNK_MAP_ZEROED ((size_t)0x04U)
#define CHUNK_MAP_LARGE ((size_t)0x02U)
#define CHUNK_MAP_ALLOCATED ((size_t)0x01U)
};

// Arena chunk header.
struct arena_chunk_t {
  // Arena that owns the chunk.
  arena_t* arena;

  // Linkage for the arena's tree of dirty chunks.
  RedBlackTreeNode<arena_chunk_t> link_dirty;

#ifdef MALLOC_DOUBLE_PURGE
  // If we're double-purging, we maintain a linked list of chunks which
  // have pages which have been madvise(MADV_FREE)'d but not explicitly
  // purged.
  //
  // We're currently lazy and don't remove a chunk from this list when
  // all its madvised pages are recommitted.
  DoublyLinkedListElement<arena_chunk_t> chunks_madvised_elem;
#endif

  // Number of dirty pages.
  size_t ndirty;

  // Map of pages within chunk that keeps track of free/large/small.
  arena_chunk_map_t map[1];  // Dynamically sized.
};

// ***************************************************************************
// Constants defining allocator size classes and behavior.

// Maximum size of L1 cache line.  This is used to avoid cache line aliasing,
// so over-estimates are okay (up to a point), but under-estimates will
// negatively affect performance.
static const size_t kCacheLineSize = 64;

// Smallest size class to support.  On Windows the smallest allocation size
// must be 8 bytes on 32-bit, 16 bytes on 64-bit.  On Linux and Mac, even
// malloc(1) must reserve a word's worth of memory (see Mozilla bug 691003).
#ifdef XP_WIN
static const size_t kMinTinyClass = sizeof(void*) * 2;
#else
static const size_t kMinTinyClass = sizeof(void*);
#endif

// Maximum tiny size class.
static const size_t kMaxTinyClass = 8;

// Amount (quantum) separating quantum-spaced size classes.
static const size_t kQuantum = 16;
static const size_t kQuantumMask = kQuantum - 1;

// Smallest quantum-spaced size classes. It could actually also be labelled a
// tiny allocation, and is spaced as such from the largest tiny size class.
// Tiny classes being powers of 2, this is twice as large as the largest of
// them.
static const size_t kMinQuantumClass = kMaxTinyClass * 2;

// Largest quantum-spaced size classes.
static const size_t kMaxQuantumClass = 512;

static_assert(kMaxQuantumClass % kQuantum == 0,
              "kMaxQuantumClass is not a multiple of kQuantum");

// Number of (2^n)-spaced tiny classes.
static const size_t kNumTinyClasses =
    LOG2(kMinQuantumClass) - LOG2(kMinTinyClass);

// Number of quantum-spaced classes.
static const size_t kNumQuantumClasses = kMaxQuantumClass / kQuantum;

// Size and alignment of memory chunks that are allocated by the OS's virtual
// memory system.
static const size_t kChunkSize = 1_MiB;
static const size_t kChunkSizeMask = kChunkSize - 1;

#ifdef MALLOC_STATIC_PAGESIZE
// VM page size. It must divide the runtime CPU page size or the code
// will abort.
// Platform specific page size conditions copied from js/public/HeapAPI.h
#if (defined(SOLARIS) || defined(__FreeBSD__)) && \
    (defined(__sparc) || defined(__sparcv9) || defined(__ia64))
static const size_t gPageSize = 8_KiB;
#elif defined(__powerpc64__)
static const size_t gPageSize = 64_KiB;
#else
static const size_t gPageSize = 4_KiB;
#endif

#else
static size_t gPageSize;
#endif

#ifdef MALLOC_STATIC_PAGESIZE
#define DECLARE_GLOBAL(type, name)
#define DEFINE_GLOBALS
#define END_GLOBALS
#define DEFINE_GLOBAL(type) static const type
#define GLOBAL_LOG2 LOG2
#define GLOBAL_ASSERT_HELPER1(x) static_assert(x, #x)
#define GLOBAL_ASSERT_HELPER2(x, y) static_assert(x, y)
#define GLOBAL_ASSERT(...)                                               \
  MACRO_CALL(                                                            \
      MOZ_PASTE_PREFIX_AND_ARG_COUNT(GLOBAL_ASSERT_HELPER, __VA_ARGS__), \
      (__VA_ARGS__))
#else
#define DECLARE_GLOBAL(type, name) static type name;
#define DEFINE_GLOBALS static void DefineGlobals() {
#define END_GLOBALS }
#define DEFINE_GLOBAL(type)
#define GLOBAL_LOG2 FloorLog2
#define GLOBAL_ASSERT MOZ_RELEASE_ASSERT
#endif

DECLARE_GLOBAL(size_t, gMaxSubPageClass)
DECLARE_GLOBAL(uint8_t, gNumSubPageClasses)
DECLARE_GLOBAL(uint8_t, gPageSize2Pow)
DECLARE_GLOBAL(size_t, gPageSizeMask)
DECLARE_GLOBAL(size_t, gChunkNumPages)
DECLARE_GLOBAL(size_t, gChunkHeaderNumPages)
DECLARE_GLOBAL(size_t, gMaxLargeClass)

DEFINE_GLOBALS
// Largest sub-page size class.
DEFINE_GLOBAL(size_t) gMaxSubPageClass = gPageSize / 2;

// Max size class for bins.
#define gMaxBinClass gMaxSubPageClass

// Number of (2^n)-spaced sub-page bins.
DEFINE_GLOBAL(uint8_t)
gNumSubPageClasses = GLOBAL_LOG2(gMaxSubPageClass) - LOG2(kMaxQuantumClass);

DEFINE_GLOBAL(uint8_t) gPageSize2Pow = GLOBAL_LOG2(gPageSize);
DEFINE_GLOBAL(size_t) gPageSizeMask = gPageSize - 1;

// Number of pages in a chunk.
DEFINE_GLOBAL(size_t) gChunkNumPages = kChunkSize >> gPageSize2Pow;

// Number of pages necessary for a chunk header.
DEFINE_GLOBAL(size_t)
gChunkHeaderNumPages =
    ((sizeof(arena_chunk_t) + sizeof(arena_chunk_map_t) * (gChunkNumPages - 1) +
      gPageSizeMask) &
     ~gPageSizeMask) >>
    gPageSize2Pow;

// Max size class for arenas.
DEFINE_GLOBAL(size_t)
gMaxLargeClass = kChunkSize - (gChunkHeaderNumPages << gPageSize2Pow);

// Various sanity checks that regard configuration.
GLOBAL_ASSERT(1ULL << gPageSize2Pow == gPageSize,
              "Page size is not a power of two");
GLOBAL_ASSERT(kQuantum >= sizeof(void*));
GLOBAL_ASSERT(kQuantum <= gPageSize);
GLOBAL_ASSERT(kChunkSize >= gPageSize);
GLOBAL_ASSERT(kQuantum * 4 <= kChunkSize);
END_GLOBALS

// Recycle at most 128 MiB of chunks. This means we retain at most
// 6.25% of the process address space on a 32-bit OS for later use.
static const size_t gRecycleLimit = 128_MiB;

// The current amount of recycled bytes, updated atomically.
static Atomic<size_t, ReleaseAcquire> gRecycledSize;

// Maximum number of dirty pages per arena.
#define DIRTY_MAX_DEFAULT (1U << 8)

static size_t opt_dirty_max = DIRTY_MAX_DEFAULT;

// Return the smallest chunk multiple that is >= s.
#define CHUNK_CEILING(s) (((s) + kChunkSizeMask) & ~kChunkSizeMask)

// Return the smallest cacheline multiple that is >= s.
#define CACHELINE_CEILING(s) \
  (((s) + (kCacheLineSize - 1)) & ~(kCacheLineSize - 1))

// Return the smallest quantum multiple that is >= a.
#define QUANTUM_CEILING(a) (((a) + (kQuantumMask)) & ~(kQuantumMask))

// Return the smallest pagesize multiple that is >= s.
#define PAGE_CEILING(s) (((s) + gPageSizeMask) & ~gPageSizeMask)

// ***************************************************************************
// MALLOC_DECOMMIT and MALLOC_DOUBLE_PURGE are mutually exclusive.
#if defined(MALLOC_DECOMMIT) && defined(MALLOC_DOUBLE_PURGE)
#error MALLOC_DECOMMIT and MALLOC_DOUBLE_PURGE are mutually exclusive.
#endif

static void* base_alloc(size_t aSize);

// Set to true once the allocator has been initialized.
#if defined(_MSC_VER) && !defined(__clang__)
// MSVC may create a static initializer for an Atomic<bool>, which may actually
// run after `malloc_init` has been called once, which triggers multiple
// initializations.
// We work around the problem by not using an Atomic<bool> at all. There is a
// theoretical problem with using `malloc_initialized` non-atomically, but
// practically, this is only true if `malloc_init` is never called before
// threads are created.
static bool malloc_initialized;
#else
static Atomic<bool> malloc_initialized;
#endif

static StaticMutex gInitLock = {STATIC_MUTEX_INIT};

// ***************************************************************************
// Statistics data structures.

struct arena_stats_t {
  // Number of bytes currently mapped.
  size_t mapped;

  // Current number of committed pages.
  size_t committed;

  // Per-size-category statistics.
  size_t allocated_small;

  size_t allocated_large;
};

// ***************************************************************************
// Extent data structures.

enum ChunkType {
  UNKNOWN_CHUNK,
  ZEROED_CHUNK,    // chunk only contains zeroes.
  ARENA_CHUNK,     // used to back arena runs created by arena_t::AllocRun.
  HUGE_CHUNK,      // used to back huge allocations (e.g. arena_t::MallocHuge).
  RECYCLED_CHUNK,  // chunk has been stored for future use by chunk_recycle.
};

// Tree of extents.
struct extent_node_t {
  // Linkage for the size/address-ordered tree.
  RedBlackTreeNode<extent_node_t> mLinkBySize;

  // Linkage for the address-ordered tree.
  RedBlackTreeNode<extent_node_t> mLinkByAddr;

  // Pointer to the extent that this tree node is responsible for.
  void* mAddr;

  // Total region size.
  size_t mSize;

  union {
    // What type of chunk is there; used for chunk recycling.
    ChunkType mChunkType;

    // A pointer to the associated arena, for huge allocations.
    arena_t* mArena;
  };
};

struct ExtentTreeSzTrait {
  static RedBlackTreeNode<extent_node_t>& GetTreeNode(extent_node_t* aThis) {
    return aThis->mLinkBySize;
  }

  static inline Order Compare(extent_node_t* aNode, extent_node_t* aOther) {
    Order ret = CompareInt(aNode->mSize, aOther->mSize);
    return (ret != Order::eEqual) ? ret
                                  : CompareAddr(aNode->mAddr, aOther->mAddr);
  }
};

struct ExtentTreeTrait {
  static RedBlackTreeNode<extent_node_t>& GetTreeNode(extent_node_t* aThis) {
    return aThis->mLinkByAddr;
  }

  static inline Order Compare(extent_node_t* aNode, extent_node_t* aOther) {
    return CompareAddr(aNode->mAddr, aOther->mAddr);
  }
};

struct ExtentTreeBoundsTrait : public ExtentTreeTrait {
  static inline Order Compare(extent_node_t* aKey, extent_node_t* aNode) {
    uintptr_t key_addr = reinterpret_cast<uintptr_t>(aKey->mAddr);
    uintptr_t node_addr = reinterpret_cast<uintptr_t>(aNode->mAddr);
    size_t node_size = aNode->mSize;

    // Is aKey within aNode?
    if (node_addr <= key_addr && key_addr < node_addr + node_size) {
      return Order::eEqual;
    }

    return CompareAddr(aKey->mAddr, aNode->mAddr);
  }
};

// Describe size classes to which allocations are rounded up to.
// TODO: add large and huge types when the arena allocation code
// changes in a way that allows it to be beneficial.
class SizeClass {
 public:
  enum ClassType {
    Tiny,
    Quantum,
    SubPage,
    Large,
  };

  explicit inline SizeClass(size_t aSize) {
    if (aSize <= kMaxTinyClass) {
      mType = Tiny;
      mSize = std::max(RoundUpPow2(aSize), kMinTinyClass);
    } else if (aSize <= kMaxQuantumClass) {
      mType = Quantum;
      mSize = QUANTUM_CEILING(aSize);
    } else if (aSize <= gMaxSubPageClass) {
      mType = SubPage;
      mSize = RoundUpPow2(aSize);
    } else if (aSize <= gMaxLargeClass) {
      mType = Large;
      mSize = PAGE_CEILING(aSize);
    } else {
      MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Invalid size");
    }
  }

  SizeClass& operator=(const SizeClass& aOther) = default;

  bool operator==(const SizeClass& aOther) { return aOther.mSize == mSize; }

  size_t Size() { return mSize; }

  ClassType Type() { return mType; }

  SizeClass Next() { return SizeClass(mSize + 1); }

 private:
  ClassType mType;
  size_t mSize;
};

// ***************************************************************************
// Radix tree data structures.
//
// The number of bits passed to the template is the number of significant bits
// in an address to do a radix lookup with.
//
// An address is looked up by splitting it in kBitsPerLevel bit chunks, except
// the most significant bits, where the bit chunk is kBitsAtLevel1 which can be
// different if Bits is not a multiple of kBitsPerLevel.
//
// With e.g. sizeof(void*)=4, Bits=16 and kBitsPerLevel=8, an address is split
// like the following:
// 0x12345678 -> mRoot[0x12][0x34]
template <size_t Bits>
class AddressRadixTree {
// Size of each radix tree node (as a power of 2).
// This impacts tree depth.
#ifdef HAVE_64BIT_BUILD
  static const size_t kNodeSize = kCacheLineSize;
#else
  static const size_t kNodeSize = 16_KiB;
#endif
  static const size_t kBitsPerLevel = LOG2(kNodeSize) - LOG2(sizeof(void*));
  static const size_t kBitsAtLevel1 =
      (Bits % kBitsPerLevel) ? Bits % kBitsPerLevel : kBitsPerLevel;
  static const size_t kHeight = (Bits + kBitsPerLevel - 1) / kBitsPerLevel;
  static_assert(kBitsAtLevel1 + (kHeight - 1) * kBitsPerLevel == Bits,
                "AddressRadixTree parameters don't work out");

  Mutex mLock;
  void** mRoot;

 public:
  bool Init();

  inline void* Get(void* aAddr);

  // Returns whether the value was properly set.
  inline bool Set(void* aAddr, void* aValue);

  inline bool Unset(void* aAddr) { return Set(aAddr, nullptr); }

 private:
  inline void** GetSlot(void* aAddr, bool aCreate = false);
};

// ***************************************************************************
// Arena data structures.

struct arena_bin_t;

struct ArenaChunkMapLink {
  static RedBlackTreeNode<arena_chunk_map_t>& GetTreeNode(
      arena_chunk_map_t* aThis) {
    return aThis->link;
  }
};

struct ArenaRunTreeTrait : public ArenaChunkMapLink {
  static inline Order Compare(arena_chunk_map_t* aNode,
                              arena_chunk_map_t* aOther) {
    MOZ_ASSERT(aNode);
    MOZ_ASSERT(aOther);
    return CompareAddr(aNode, aOther);
  }
};

struct ArenaAvailTreeTrait : public ArenaChunkMapLink {
  static inline Order Compare(arena_chunk_map_t* aNode,
                              arena_chunk_map_t* aOther) {
    size_t size1 = aNode->bits & ~gPageSizeMask;
    size_t size2 = aOther->bits & ~gPageSizeMask;
    Order ret = CompareInt(size1, size2);
    return (ret != Order::eEqual)
               ? ret
               : CompareAddr((aNode->bits & CHUNK_MAP_KEY) ? nullptr : aNode,
                             aOther);
  }
};

struct ArenaDirtyChunkTrait {
  static RedBlackTreeNode<arena_chunk_t>& GetTreeNode(arena_chunk_t* aThis) {
    return aThis->link_dirty;
  }

  static inline Order Compare(arena_chunk_t* aNode, arena_chunk_t* aOther) {
    MOZ_ASSERT(aNode);
    MOZ_ASSERT(aOther);
    return CompareAddr(aNode, aOther);
  }
};

#ifdef MALLOC_DOUBLE_PURGE
namespace mozilla {

template <>
struct GetDoublyLinkedListElement<arena_chunk_t> {
  static DoublyLinkedListElement<arena_chunk_t>& Get(arena_chunk_t* aThis) {
    return aThis->chunks_madvised_elem;
  }
};
}  // namespace mozilla
#endif

struct arena_run_t {
#if defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
  uint32_t mMagic;
#define ARENA_RUN_MAGIC 0x384adf93

  // On 64-bit platforms, having the arena_bin_t pointer following
  // the mMagic field means there's padding between both fields, making
  // the run header larger than necessary.
  // But when MOZ_DIAGNOSTIC_ASSERT_ENABLED is not set, starting the
  // header with this field followed by the arena_bin_t pointer yields
  // the same padding. We do want the mMagic field to appear first, so
  // depending whether MOZ_DIAGNOSTIC_ASSERT_ENABLED is set or not, we
  // move some field to avoid padding.

  // Number of free regions in run.
  unsigned mNumFree;
#endif

  // Bin this run is associated with.
  arena_bin_t* mBin;

  // Index of first element that might have a free region.
  unsigned mRegionsMinElement;

#if !defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
  // Number of free regions in run.
  unsigned mNumFree;
#endif

  // Bitmask of in-use regions (0: in use, 1: free).
  unsigned mRegionsMask[1];  // Dynamically sized.
};

struct arena_bin_t {
  // Current run being used to service allocations of this bin's size
  // class.
  arena_run_t* mCurrentRun;

  // Tree of non-full runs.  This tree is used when looking for an
  // existing run when mCurrentRun is no longer usable.  We choose the
  // non-full run that is lowest in memory; this policy tends to keep
  // objects packed well, and it can also help reduce the number of
  // almost-empty chunks.
  RedBlackTree<arena_chunk_map_t, ArenaRunTreeTrait> mNonFullRuns;

  // Bin's size class.
  size_t mSizeClass;

  // Total size of a run for this bin's size class.
  size_t mRunSize;

  // Total number of regions in a run for this bin's size class.
  uint32_t mRunNumRegions;

  // Number of elements in a run's mRegionsMask for this bin's size class.
  uint32_t mRunNumRegionsMask;

  // Offset of first region in a run for this bin's size class.
  uint32_t mRunFirstRegionOffset;

  // Current number of runs in this bin, full or otherwise.
  unsigned long mNumRuns;

  // Amount of overhead runs are allowed to have.
  static constexpr double kRunOverhead = 1.6_percent;
  static constexpr double kRunRelaxedOverhead = 2.4_percent;

  // Initialize a bin for the given size class.
  // The generated run sizes, for a page size of 4 KiB, are:
  //   size|run       size|run       size|run       size|run
  //  class|size     class|size     class|size     class|size
  //     4   4 KiB      8   4 KiB     16   4 KiB     32   4 KiB
  //    48   4 KiB     64   4 KiB     80   4 KiB     96   4 KiB
  //   112   4 KiB    128   8 KiB    144   4 KiB    160   8 KiB
  //   176   4 KiB    192   4 KiB    208   8 KiB    224   4 KiB
  //   240   4 KiB    256  16 KiB    272   4 KiB    288   4 KiB
  //   304  12 KiB    320  12 KiB    336   4 KiB    352   8 KiB
  //   368   4 KiB    384   8 KiB    400  20 KiB    416  16 KiB
  //   432  12 KiB    448   4 KiB    464  16 KiB    480   8 KiB
  //   496  20 KiB    512  32 KiB   1024  64 KiB   2048 128 KiB
  inline void Init(SizeClass aSizeClass);
};

struct arena_t {
#if defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
  uint32_t mMagic;
#define ARENA_MAGIC 0x947d3d24
#endif

  arena_id_t mId;
  // Linkage for the tree of arenas by id.
  RedBlackTreeNode<arena_t> mLink;

  // All operations on this arena require that lock be locked.
  Mutex mLock;

  arena_stats_t mStats;

 private:
  // Tree of dirty-page-containing chunks this arena manages.
  RedBlackTree<arena_chunk_t, ArenaDirtyChunkTrait> mChunksDirty;

#ifdef MALLOC_DOUBLE_PURGE
  // Head of a linked list of MADV_FREE'd-page-containing chunks this
  // arena manages.
  DoublyLinkedList<arena_chunk_t> mChunksMAdvised;
#endif

  // In order to avoid rapid chunk allocation/deallocation when an arena
  // oscillates right on the cusp of needing a new chunk, cache the most
  // recently freed chunk.  The spare is left in the arena's chunk trees
  // until it is deleted.
  //
  // There is one spare chunk per arena, rather than one spare total, in
  // order to avoid interactions between multiple threads that could make
  // a single spare inadequate.
  arena_chunk_t* mSpare;

 public:
  // Current count of pages within unused runs that are potentially
  // dirty, and for which madvise(... MADV_FREE) has not been called.  By
  // tracking this, we can institute a limit on how much dirty unused
  // memory is mapped for each arena.
  size_t mNumDirty;

  // Maximum value allowed for mNumDirty.
  size_t mMaxDirty;

 private:
  // Size/address-ordered tree of this arena's available runs.  This tree
  // is used for first-best-fit run allocation.
  RedBlackTree<arena_chunk_map_t, ArenaAvailTreeTrait> mRunsAvail;

 public:
  // mBins is used to store rings of free regions of the following sizes,
  // assuming a 16-byte quantum, 4kB pagesize, and default MALLOC_OPTIONS.
  //
  //   mBins[i] | size |
  //   --------+------+
  //        0  |    2 |
  //        1  |    4 |
  //        2  |    8 |
  //   --------+------+
  //        3  |   16 |
  //        4  |   32 |
  //        5  |   48 |
  //        6  |   64 |
  //           :      :
  //           :      :
  //       33  |  496 |
  //       34  |  512 |
  //   --------+------+
  //       35  | 1024 |
  //       36  | 2048 |
  //   --------+------+
  arena_bin_t mBins[1];  // Dynamically sized.

  explicit arena_t(arena_params_t* aParams);

 private:
  void InitChunk(arena_chunk_t* aChunk, bool aZeroed);

  void DeallocChunk(arena_chunk_t* aChunk);

  arena_run_t* AllocRun(size_t aSize, bool aLarge, bool aZero);

  void DallocRun(arena_run_t* aRun, bool aDirty);

  MOZ_MUST_USE bool SplitRun(arena_run_t* aRun, size_t aSize, bool aLarge,
                             bool aZero);

  void TrimRunHead(arena_chunk_t* aChunk, arena_run_t* aRun, size_t aOldSize,
                   size_t aNewSize);

  void TrimRunTail(arena_chunk_t* aChunk, arena_run_t* aRun, size_t aOldSize,
                   size_t aNewSize, bool dirty);

  arena_run_t* GetNonFullBinRun(arena_bin_t* aBin);

  inline void* MallocSmall(size_t aSize, bool aZero);

  void* MallocLarge(size_t aSize, bool aZero);

  void* MallocHuge(size_t aSize, bool aZero);

  void* PallocLarge(size_t aAlignment, size_t aSize, size_t aAllocSize);

  void* PallocHuge(size_t aSize, size_t aAlignment, bool aZero);

  void RallocShrinkLarge(arena_chunk_t* aChunk, void* aPtr, size_t aSize,
                         size_t aOldSize);

  bool RallocGrowLarge(arena_chunk_t* aChunk, void* aPtr, size_t aSize,
                       size_t aOldSize);

  void* RallocSmallOrLarge(void* aPtr, size_t aSize, size_t aOldSize);

  void* RallocHuge(void* aPtr, size_t aSize, size_t aOldSize);

 public:
  inline void* Malloc(size_t aSize, bool aZero);

  void* Palloc(size_t aAlignment, size_t aSize);

  inline void DallocSmall(arena_chunk_t* aChunk, void* aPtr,
                          arena_chunk_map_t* aMapElm);

  void DallocLarge(arena_chunk_t* aChunk, void* aPtr);

  void* Ralloc(void* aPtr, size_t aSize, size_t aOldSize);

  void Purge(bool aAll);

  void HardPurge();

  void* operator new(size_t aCount) = delete;

  void* operator new(size_t aCount, const fallible_t&)
#if !defined(_MSC_VER) || defined(_CPPUNWIND)
      noexcept
#endif
  {
    MOZ_ASSERT(aCount == sizeof(arena_t));
    // Allocate enough space for trailing bins.
    return base_alloc(
        aCount + (sizeof(arena_bin_t) * (kNumTinyClasses + kNumQuantumClasses +
                                         gNumSubPageClasses - 1)));
  }

  void operator delete(void*) = delete;
};

struct ArenaTreeTrait {
  static RedBlackTreeNode<arena_t>& GetTreeNode(arena_t* aThis) {
    return aThis->mLink;
  }

  static inline Order Compare(arena_t* aNode, arena_t* aOther) {
    MOZ_ASSERT(aNode);
    MOZ_ASSERT(aOther);
    return CompareInt(aNode->mId, aOther->mId);
  }
};

// Bookkeeping for all the arenas used by the allocator.
// Arenas are separated in two categories:
// - "private" arenas, used through the moz_arena_* API
// - all the other arenas: the default arena, and thread-local arenas,
//   used by the standard API.
class ArenaCollection {
 public:
  bool Init() {
    mArenas.Init();
    mPrivateArenas.Init();
    arena_params_t params;
    // The main arena allows more dirty pages than the default for other arenas.
    params.mMaxDirty = opt_dirty_max;
    mDefaultArena =
        mLock.Init() ? CreateArena(/* IsPrivate = */ false, &params) : nullptr;
    return bool(mDefaultArena);
  }

  inline arena_t* GetById(arena_id_t aArenaId, bool aIsPrivate);

  arena_t* CreateArena(bool aIsPrivate, arena_params_t* aParams);

  void DisposeArena(arena_t* aArena) {
    MutexAutoLock lock(mLock);
    (mPrivateArenas.Search(aArena) ? mPrivateArenas : mArenas).Remove(aArena);
    // The arena is leaked, and remaining allocations in it still are alive
    // until they are freed. After that, the arena will be empty but still
    // taking have at least a chunk taking address space. TODO: bug 1364359.
  }

  using Tree = RedBlackTree<arena_t, ArenaTreeTrait>;

  struct Iterator : Tree::Iterator {
    explicit Iterator(Tree* aTree, Tree* aSecondTree)
        : Tree::Iterator(aTree), mNextTree(aSecondTree) {}

    Item<Iterator> begin() {
      return Item<Iterator>(this, *Tree::Iterator::begin());
    }

    Item<Iterator> end() { return Item<Iterator>(this, nullptr); }

    arena_t* Next() {
      arena_t* result = Tree::Iterator::Next();
      if (!result && mNextTree) {
        new (this) Iterator(mNextTree, nullptr);
        result = *Tree::Iterator::begin();
      }
      return result;
    }

   private:
    Tree* mNextTree;
  };

  Iterator iter() { return Iterator(&mArenas, &mPrivateArenas); }

  inline arena_t* GetDefault() { return mDefaultArena; }

  Mutex mLock;

 private:
  arena_t* mDefaultArena;
  arena_id_t mLastArenaId;
  Tree mArenas;
  Tree mPrivateArenas;
};

static ArenaCollection gArenas;

// ******
// Chunks.
static AddressRadixTree<(sizeof(void*) << 3) - LOG2(kChunkSize)> gChunkRTree;

// Protects chunk-related data structures.
static Mutex chunks_mtx;

// Trees of chunks that were previously allocated (trees differ only in node
// ordering).  These are used when allocating chunks, in an attempt to re-use
// address space.  Depending on function, different tree orderings are needed,
// which is why there are two trees with the same contents.
static RedBlackTree<extent_node_t, ExtentTreeSzTrait> gChunksBySize;
static RedBlackTree<extent_node_t, ExtentTreeTrait> gChunksByAddress;

// Protects huge allocation-related data structures.
static Mutex huge_mtx;

// Tree of chunks that are stand-alone huge allocations.
static RedBlackTree<extent_node_t, ExtentTreeTrait> huge;

// Huge allocation statistics.
static size_t huge_allocated;
static size_t huge_mapped;

// **************************
// base (internal allocation).

// Current pages that are being used for internal memory allocations.  These
// pages are carved up in cacheline-size quanta, so that there is no chance of
// false cache line sharing.

static void* base_pages;
static void* base_next_addr;
static void* base_next_decommitted;
static void* base_past_addr;  // Addr immediately past base_pages.
static extent_node_t* base_nodes;
static Mutex base_mtx;
static size_t base_mapped;
static size_t base_committed;

// ******
// Arenas.

// The arena associated with the current thread (per
// jemalloc_thread_local_arena) On OSX, __thread/thread_local circles back
// calling malloc to allocate storage on first access on each thread, which
// leads to an infinite loop, but pthread-based TLS somehow doesn't have this
// problem.
#if !defined(XP_DARWIN)
static MOZ_THREAD_LOCAL(arena_t*) thread_arena;
#else
static detail::ThreadLocal<arena_t*, detail::ThreadLocalKeyStorage>
    thread_arena;
#endif

// *****************************
// Runtime configuration options.

const uint8_t kAllocJunk = 0xe4;
const uint8_t kAllocPoison = 0xe5;

#ifdef MOZ_DEBUG
static bool opt_junk = true;
static bool opt_zero = false;
#else
static const bool opt_junk = false;
static const bool opt_zero = false;
#endif

// ***************************************************************************
// Begin forward declarations.

static void* chunk_alloc(size_t aSize, size_t aAlignment, bool aBase,
                         bool* aZeroed = nullptr);
static void chunk_dealloc(void* aChunk, size_t aSize, ChunkType aType);
static void chunk_ensure_zero(void* aPtr, size_t aSize, bool aZeroed);
static void huge_dalloc(void* aPtr, arena_t* aArena);
static bool malloc_init_hard();

#ifdef XP_DARWIN
#define FORK_HOOK extern "C"
#else
#define FORK_HOOK static
#endif
FORK_HOOK void _malloc_prefork(void);
FORK_HOOK void _malloc_postfork_parent(void);
FORK_HOOK void _malloc_postfork_child(void);

// End forward declarations.
// ***************************************************************************

// FreeBSD's pthreads implementation calls malloc(3), so the malloc
// implementation has to take pains to avoid infinite recursion during
// initialization.
// Returns whether the allocator was successfully initialized.
static inline bool malloc_init() {
  if (malloc_initialized == false) {
    return malloc_init_hard();
  }

  return true;
}

static void _malloc_message(const char* p) {
#if !defined(XP_WIN)
#define _write write
#endif
  // Pretend to check _write() errors to suppress gcc warnings about
  // warn_unused_result annotations in some versions of glibc headers.
  if (_write(STDERR_FILENO, p, (unsigned int)strlen(p)) < 0) {
    return;
  }
}

template <typename... Args>
static void _malloc_message(const char* p, Args... args) {
  _malloc_message(p);
  _malloc_message(args...);
}

#ifdef ANDROID
// Android's pthread.h does not declare pthread_atfork() until SDK 21.
extern "C" MOZ_EXPORT int pthread_atfork(void (*)(void), void (*)(void),
                                         void (*)(void));
#endif

// ***************************************************************************
// Begin Utility functions/macros.

// Return the chunk address for allocation address a.
static inline arena_chunk_t* GetChunkForPtr(const void* aPtr) {
  return (arena_chunk_t*)(uintptr_t(aPtr) & ~kChunkSizeMask);
}

// Return the chunk offset of address a.
static inline size_t GetChunkOffsetForPtr(const void* aPtr) {
  return (size_t)(uintptr_t(aPtr) & kChunkSizeMask);
}

static inline const char* _getprogname(void) { return "<jemalloc>"; }

// Fill the given range of memory with zeroes or junk depending on opt_junk and
// opt_zero. Callers can force filling with zeroes through the aForceZero
// argument.
static inline void ApplyZeroOrJunk(void* aPtr, size_t aSize) {
  if (opt_junk) {
    memset(aPtr, kAllocJunk, aSize);
  } else if (opt_zero) {
    memset(aPtr, 0, aSize);
  }
}

// ***************************************************************************

static inline void pages_decommit(void* aAddr, size_t aSize) {
#ifdef XP_WIN
  // The region starting at addr may have been allocated in multiple calls
  // to VirtualAlloc and recycled, so decommitting the entire region in one
  // go may not be valid. However, since we allocate at least a chunk at a
  // time, we may touch any region in chunksized increments.
  size_t pages_size = std::min(aSize, kChunkSize - GetChunkOffsetForPtr(aAddr));
  while (aSize > 0) {
    if (!VirtualFree(aAddr, pages_size, MEM_DECOMMIT)) {
      MOZ_CRASH();
    }
    aAddr = (void*)((uintptr_t)aAddr + pages_size);
    aSize -= pages_size;
    pages_size = std::min(aSize, kChunkSize);
  }
#else
  if (mmap(aAddr, aSize, PROT_NONE, MAP_FIXED | MAP_PRIVATE | MAP_ANON, -1,
           0) == MAP_FAILED) {
    MOZ_CRASH();
  }
  MozTagAnonymousMemory(aAddr, aSize, "jemalloc-decommitted");
#endif
}

// Commit pages. Returns whether pages were committed.
MOZ_MUST_USE static inline bool pages_commit(void* aAddr, size_t aSize) {
#ifdef XP_WIN
  // The region starting at addr may have been allocated in multiple calls
  // to VirtualAlloc and recycled, so committing the entire region in one
  // go may not be valid. However, since we allocate at least a chunk at a
  // time, we may touch any region in chunksized increments.
  size_t pages_size = std::min(aSize, kChunkSize - GetChunkOffsetForPtr(aAddr));
  while (aSize > 0) {
    if (!VirtualAlloc(aAddr, pages_size, MEM_COMMIT, PAGE_READWRITE)) {
      return false;
    }
    aAddr = (void*)((uintptr_t)aAddr + pages_size);
    aSize -= pages_size;
    pages_size = std::min(aSize, kChunkSize);
  }
#else
  if (mmap(aAddr, aSize, PROT_READ | PROT_WRITE,
           MAP_FIXED | MAP_PRIVATE | MAP_ANON, -1, 0) == MAP_FAILED) {
    return false;
  }
  MozTagAnonymousMemory(aAddr, aSize, "jemalloc");
#endif
  return true;
}

static bool base_pages_alloc(size_t minsize) {
  size_t csize;
  size_t pminsize;

  MOZ_ASSERT(minsize != 0);
  csize = CHUNK_CEILING(minsize);
  base_pages = chunk_alloc(csize, kChunkSize, true);
  if (!base_pages) {
    return true;
  }
  base_next_addr = base_pages;
  base_past_addr = (void*)((uintptr_t)base_pages + csize);
  // Leave enough pages for minsize committed, since otherwise they would
  // have to be immediately recommitted.
  pminsize = PAGE_CEILING(minsize);
  base_next_decommitted = (void*)((uintptr_t)base_pages + pminsize);
#if defined(MALLOC_DECOMMIT)
  if (pminsize < csize) {
    pages_decommit(base_next_decommitted, csize - pminsize);
  }
#endif
  base_mapped += csize;
  base_committed += pminsize;

  return false;
}

static void* base_alloc(size_t aSize) {
  void* ret;
  size_t csize;

  // Round size up to nearest multiple of the cacheline size.
  csize = CACHELINE_CEILING(aSize);

  MutexAutoLock lock(base_mtx);
  // Make sure there's enough space for the allocation.
  if ((uintptr_t)base_next_addr + csize > (uintptr_t)base_past_addr) {
    if (base_pages_alloc(csize)) {
      return nullptr;
    }
  }
  // Allocate.
  ret = base_next_addr;
  base_next_addr = (void*)((uintptr_t)base_next_addr + csize);
  // Make sure enough pages are committed for the new allocation.
  if ((uintptr_t)base_next_addr > (uintptr_t)base_next_decommitted) {
    void* pbase_next_addr = (void*)(PAGE_CEILING((uintptr_t)base_next_addr));

#ifdef MALLOC_DECOMMIT
    if (!pages_commit(
            base_next_decommitted,
            (uintptr_t)pbase_next_addr - (uintptr_t)base_next_decommitted)) {
      return nullptr;
    }
#endif
    base_committed +=
        (uintptr_t)pbase_next_addr - (uintptr_t)base_next_decommitted;
    base_next_decommitted = pbase_next_addr;
  }

  return ret;
}

static void* base_calloc(size_t aNumber, size_t aSize) {
  void* ret = base_alloc(aNumber * aSize);
  if (ret) {
    memset(ret, 0, aNumber * aSize);
  }
  return ret;
}

static extent_node_t* base_node_alloc(void) {
  extent_node_t* ret;

  base_mtx.Lock();
  if (base_nodes) {
    ret = base_nodes;
    base_nodes = *(extent_node_t**)ret;
    base_mtx.Unlock();
  } else {
    base_mtx.Unlock();
    ret = (extent_node_t*)base_alloc(sizeof(extent_node_t));
  }

  return ret;
}

static void base_node_dealloc(extent_node_t* aNode) {
  MutexAutoLock lock(base_mtx);
  *(extent_node_t**)aNode = base_nodes;
  base_nodes = aNode;
}

struct BaseNodeFreePolicy {
  void operator()(extent_node_t* aPtr) { base_node_dealloc(aPtr); }
};

using UniqueBaseNode = UniquePtr<extent_node_t, BaseNodeFreePolicy>;

// End Utility functions/macros.
// ***************************************************************************
// Begin chunk management functions.

#ifdef XP_WIN

static void* pages_map(void* aAddr, size_t aSize) {
  void* ret = nullptr;
  ret = VirtualAlloc(aAddr, aSize, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
  return ret;
}

static void pages_unmap(void* aAddr, size_t aSize) {
  if (VirtualFree(aAddr, 0, MEM_RELEASE) == 0) {
    _malloc_message(_getprogname(), ": (malloc) Error in VirtualFree()\n");
  }
}
#else

static void pages_unmap(void* aAddr, size_t aSize) {
  if (munmap(aAddr, aSize) == -1) {
    char buf[64];

    if (strerror_r(errno, buf, sizeof(buf)) == 0) {
      _malloc_message(_getprogname(), ": (malloc) Error in munmap(): ", buf,
                      "\n");
    }
  }
}

static void* pages_map(void* aAddr, size_t aSize) {
  void* ret;
#if defined(__ia64__) || \
    (defined(__sparc__) && defined(__arch64__) && defined(__linux__))
  // The JS engine assumes that all allocated pointers have their high 17 bits
  // clear, which ia64's mmap doesn't support directly. However, we can emulate
  // it by passing mmap an "addr" parameter with those bits clear. The mmap will
  // return that address, or the nearest available memory above that address,
  // providing a near-guarantee that those bits are clear. If they are not, we
  // return nullptr below to indicate out-of-memory.
  //
  // The addr is chosen as 0x0000070000000000, which still allows about 120TB of
  // virtual address space.
  //
  // See Bug 589735 for more information.
  bool check_placement = true;
  if (!aAddr) {
    aAddr = (void*)0x0000070000000000;
    check_placement = false;
  }
#endif

#if defined(__sparc__) && defined(__arch64__) && defined(__linux__)
  const uintptr_t start = 0x0000070000000000ULL;
  const uintptr_t end = 0x0000800000000000ULL;

  // Copied from js/src/gc/Memory.cpp and adapted for this source
  uintptr_t hint;
  void* region = MAP_FAILED;
  for (hint = start; region == MAP_FAILED && hint + aSize <= end;
       hint += kChunkSize) {
    region = mmap((void*)hint, aSize, PROT_READ | PROT_WRITE,
                  MAP_PRIVATE | MAP_ANON, -1, 0);
    if (region != MAP_FAILED) {
      if (((size_t)region + (aSize - 1)) & 0xffff800000000000) {
        if (munmap(region, aSize)) {
          MOZ_ASSERT(errno == ENOMEM);
        }
        region = MAP_FAILED;
      }
    }
  }
  ret = region;
#else
  // We don't use MAP_FIXED here, because it can cause the *replacement*
  // of existing mappings, and we only want to create new mappings.
  ret =
      mmap(aAddr, aSize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
  MOZ_ASSERT(ret);
#endif
  if (ret == MAP_FAILED) {
    ret = nullptr;
  }
#if defined(__ia64__) || \
    (defined(__sparc__) && defined(__arch64__) && defined(__linux__))
  // If the allocated memory doesn't have its upper 17 bits clear, consider it
  // as out of memory.
  else if ((long long)ret & 0xffff800000000000) {
    munmap(ret, aSize);
    ret = nullptr;
  }
  // If the caller requested a specific memory location, verify that's what mmap
  // returned.
  else if (check_placement && ret != aAddr) {
#else
  else if (aAddr && ret != aAddr) {
#endif
    // We succeeded in mapping memory, but not in the right place.
    pages_unmap(ret, aSize);
    ret = nullptr;
  }
  if (ret) {
    MozTagAnonymousMemory(ret, aSize, "jemalloc");
  }

#if defined(__ia64__) || \
    (defined(__sparc__) && defined(__arch64__) && defined(__linux__))
  MOZ_ASSERT(!ret || (!check_placement && ret) ||
             (check_placement && ret == aAddr));
#else
  MOZ_ASSERT(!ret || (!aAddr && ret != aAddr) || (aAddr && ret == aAddr));
#endif
  return ret;
}
#endif

#ifdef XP_DARWIN
#define VM_COPY_MIN (gPageSize * 32)
static inline void pages_copy(void* dest, const void* src, size_t n) {
  MOZ_ASSERT((void*)((uintptr_t)dest & ~gPageSizeMask) == dest);
  MOZ_ASSERT(n >= VM_COPY_MIN);
  MOZ_ASSERT((void*)((uintptr_t)src & ~gPageSizeMask) == src);

  vm_copy(mach_task_self(), (vm_address_t)src, (vm_size_t)n,
          (vm_address_t)dest);
}
#endif

template <size_t Bits>
bool AddressRadixTree<Bits>::Init() {
  mLock.Init();
  mRoot = (void**)base_calloc(1 << kBitsAtLevel1, sizeof(void*));
  return mRoot;
}

template <size_t Bits>
void** AddressRadixTree<Bits>::GetSlot(void* aKey, bool aCreate) {
  uintptr_t key = reinterpret_cast<uintptr_t>(aKey);
  uintptr_t subkey;
  unsigned i, lshift, height, bits;
  void** node;
  void** child;

  for (i = lshift = 0, height = kHeight, node = mRoot; i < height - 1;
       i++, lshift += bits, node = child) {
    bits = i ? kBitsPerLevel : kBitsAtLevel1;
    subkey = (key << lshift) >> ((sizeof(void*) << 3) - bits);
    child = (void**)node[subkey];
    if (!child && aCreate) {
      child = (void**)base_calloc(1 << kBitsPerLevel, sizeof(void*));
      if (child) {
        node[subkey] = child;
      }
    }
    if (!child) {
      return nullptr;
    }
  }

  // node is a leaf, so it contains values rather than node
  // pointers.
  bits = i ? kBitsPerLevel : kBitsAtLevel1;
  subkey = (key << lshift) >> ((sizeof(void*) << 3) - bits);
  return &node[subkey];
}

template <size_t Bits>
void* AddressRadixTree<Bits>::Get(void* aKey) {
  void* ret = nullptr;

  void** slot = GetSlot(aKey);

  if (slot) {
    ret = *slot;
  }
#ifdef MOZ_DEBUG
  MutexAutoLock lock(mLock);

  // Suppose that it were possible for a jemalloc-allocated chunk to be
  // munmap()ped, followed by a different allocator in another thread re-using
  // overlapping virtual memory, all without invalidating the cached rtree
  // value.  The result would be a false positive (the rtree would claim that
  // jemalloc owns memory that it had actually discarded).  I don't think this
  // scenario is possible, but the following assertion is a prudent sanity
  // check.
  if (!slot) {
    // In case a slot has been created in the meantime.
    slot = GetSlot(aKey);
  }
  if (slot) {
    // The MutexAutoLock above should act as a memory barrier, forcing
    // the compiler to emit a new read instruction for *slot.
    MOZ_ASSERT(ret == *slot);
  } else {
    MOZ_ASSERT(ret == nullptr);
  }
#endif
  return ret;
}

template <size_t Bits>
bool AddressRadixTree<Bits>::Set(void* aKey, void* aValue) {
  MutexAutoLock lock(mLock);
  void** slot = GetSlot(aKey, /* create = */ true);
  if (slot) {
    *slot = aValue;
  }
  return slot;
}

// pages_trim, chunk_alloc_mmap_slow and chunk_alloc_mmap were cherry-picked
// from upstream jemalloc 3.4.1 to fix Mozilla bug 956501.

// Return the offset between a and the nearest aligned address at or below a.
#define ALIGNMENT_ADDR2OFFSET(a, alignment) \
  ((size_t)((uintptr_t)(a) & (alignment - 1)))

// Return the smallest alignment multiple that is >= s.
#define ALIGNMENT_CEILING(s, alignment) \
  (((s) + (alignment - 1)) & (~(alignment - 1)))

static void* pages_trim(void* addr, size_t alloc_size, size_t leadsize,
                        size_t size) {
  void* ret = (void*)((uintptr_t)addr + leadsize);

  MOZ_ASSERT(alloc_size >= leadsize + size);
#ifdef XP_WIN
  {
    void* new_addr;

    pages_unmap(addr, alloc_size);
    new_addr = pages_map(ret, size);
    if (new_addr == ret) {
      return ret;
    }
    if (new_addr) {
      pages_unmap(new_addr, size);
    }
    return nullptr;
  }
#else
  {
    size_t trailsize = alloc_size - leadsize - size;

    if (leadsize != 0) {
      pages_unmap(addr, leadsize);
    }
    if (trailsize != 0) {
      pages_unmap((void*)((uintptr_t)ret + size), trailsize);
    }
    return ret;
  }
#endif
}

static void* chunk_alloc_mmap_slow(size_t size, size_t alignment) {
  void *ret, *pages;
  size_t alloc_size, leadsize;

  alloc_size = size + alignment - gPageSize;
  // Beware size_t wrap-around.
  if (alloc_size < size) {
    return nullptr;
  }
  do {
    pages = pages_map(nullptr, alloc_size);
    if (!pages) {
      return nullptr;
    }
    leadsize =
        ALIGNMENT_CEILING((uintptr_t)pages, alignment) - (uintptr_t)pages;
    ret = pages_trim(pages, alloc_size, leadsize, size);
  } while (!ret);

  MOZ_ASSERT(ret);
  return ret;
}

static void* chunk_alloc_mmap(size_t size, size_t alignment) {
  void* ret;
  size_t offset;

  // Ideally, there would be a way to specify alignment to mmap() (like
  // NetBSD has), but in the absence of such a feature, we have to work
  // hard to efficiently create aligned mappings. The reliable, but
  // slow method is to create a mapping that is over-sized, then trim the
  // excess. However, that always results in one or two calls to
  // pages_unmap().
  //
  // Optimistically try mapping precisely the right amount before falling
  // back to the slow method, with the expectation that the optimistic
  // approach works most of the time.
  ret = pages_map(nullptr, size);
  if (!ret) {
    return nullptr;
  }
  offset = ALIGNMENT_ADDR2OFFSET(ret, alignment);
  if (offset != 0) {
    pages_unmap(ret, size);
    return chunk_alloc_mmap_slow(size, alignment);
  }

  MOZ_ASSERT(ret);
  return ret;
}

// Purge and release the pages in the chunk of length `length` at `addr` to
// the OS.
// Returns whether the pages are guaranteed to be full of zeroes when the
// function returns.
// The force_zero argument explicitly requests that the memory is guaranteed
// to be full of zeroes when the function returns.
static bool pages_purge(void* addr, size_t length, bool force_zero) {
#ifdef MALLOC_DECOMMIT
  pages_decommit(addr, length);
  return true;
#else
#ifndef XP_LINUX
  if (force_zero) {
    memset(addr, 0, length);
  }
#endif
#ifdef XP_WIN
  // The region starting at addr may have been allocated in multiple calls
  // to VirtualAlloc and recycled, so resetting the entire region in one
  // go may not be valid. However, since we allocate at least a chunk at a
  // time, we may touch any region in chunksized increments.
  size_t pages_size = std::min(length, kChunkSize - GetChunkOffsetForPtr(addr));
  while (length > 0) {
    VirtualAlloc(addr, pages_size, MEM_RESET, PAGE_READWRITE);
    addr = (void*)((uintptr_t)addr + pages_size);
    length -= pages_size;
    pages_size = std::min(length, kChunkSize);
  }
  return force_zero;
#else
#ifdef XP_LINUX
#define JEMALLOC_MADV_PURGE MADV_DONTNEED
#define JEMALLOC_MADV_ZEROS true
#else  // FreeBSD and Darwin.
#define JEMALLOC_MADV_PURGE MADV_FREE
#define JEMALLOC_MADV_ZEROS force_zero
#endif
  int err = madvise(addr, length, JEMALLOC_MADV_PURGE);
  return JEMALLOC_MADV_ZEROS && err == 0;
#undef JEMALLOC_MADV_PURGE
#undef JEMALLOC_MADV_ZEROS
#endif
#endif
}

static void* chunk_recycle(size_t aSize, size_t aAlignment, bool* aZeroed) {
  extent_node_t key;

  size_t alloc_size = aSize + aAlignment - kChunkSize;
  // Beware size_t wrap-around.
  if (alloc_size < aSize) {
    return nullptr;
  }
  key.mAddr = nullptr;
  key.mSize = alloc_size;
  chunks_mtx.Lock();
  extent_node_t* node = gChunksBySize.SearchOrNext(&key);
  if (!node) {
    chunks_mtx.Unlock();
    return nullptr;
  }
  size_t leadsize = ALIGNMENT_CEILING((uintptr_t)node->mAddr, aAlignment) -
                    (uintptr_t)node->mAddr;
  MOZ_ASSERT(node->mSize >= leadsize + aSize);
  size_t trailsize = node->mSize - leadsize - aSize;
  void* ret = (void*)((uintptr_t)node->mAddr + leadsize);
  ChunkType chunk_type = node->mChunkType;
  if (aZeroed) {
    *aZeroed = (chunk_type == ZEROED_CHUNK);
  }
  // Remove node from the tree.
  gChunksBySize.Remove(node);
  gChunksByAddress.Remove(node);
  if (leadsize != 0) {
    // Insert the leading space as a smaller chunk.
    node->mSize = leadsize;
    gChunksBySize.Insert(node);
    gChunksByAddress.Insert(node);
    node = nullptr;
  }
  if (trailsize != 0) {
    // Insert the trailing space as a smaller chunk.
    if (!node) {
      // An additional node is required, but
      // base_node_alloc() can cause a new base chunk to be
      // allocated.  Drop chunks_mtx in order to avoid
      // deadlock, and if node allocation fails, deallocate
      // the result before returning an error.
      chunks_mtx.Unlock();
      node = base_node_alloc();
      if (!node) {
        chunk_dealloc(ret, aSize, chunk_type);
        return nullptr;
      }
      chunks_mtx.Lock();
    }
    node->mAddr = (void*)((uintptr_t)(ret) + aSize);
    node->mSize = trailsize;
    node->mChunkType = chunk_type;
    gChunksBySize.Insert(node);
    gChunksByAddress.Insert(node);
    node = nullptr;
  }

  gRecycledSize -= aSize;

  chunks_mtx.Unlock();

  if (node) {
    base_node_dealloc(node);
  }
#ifdef MALLOC_DECOMMIT
  if (!pages_commit(ret, aSize)) {
    return nullptr;
  }
  // pages_commit is guaranteed to zero the chunk.
  if (aZeroed) {
    *aZeroed = true;
  }
#endif
  return ret;
}

#ifdef XP_WIN
// On Windows, calls to VirtualAlloc and VirtualFree must be matched, making it
// awkward to recycle allocations of varying sizes. Therefore we only allow
// recycling when the size equals the chunksize, unless deallocation is entirely
// disabled.
#define CAN_RECYCLE(size) (size == kChunkSize)
#else
#define CAN_RECYCLE(size) true
#endif

// Allocates `size` bytes of system memory aligned for `alignment`.
// `base` indicates whether the memory will be used for the base allocator
// (e.g. base_alloc).
// `zeroed` is an outvalue that returns whether the allocated memory is
// guaranteed to be full of zeroes. It can be omitted when the caller doesn't
// care about the result.
static void* chunk_alloc(size_t aSize, size_t aAlignment, bool aBase,
                         bool* aZeroed) {
  void* ret = nullptr;

  MOZ_ASSERT(aSize != 0);
  MOZ_ASSERT((aSize & kChunkSizeMask) == 0);
  MOZ_ASSERT(aAlignment != 0);
  MOZ_ASSERT((aAlignment & kChunkSizeMask) == 0);

  // Base allocations can't be fulfilled by recycling because of
  // possible deadlock or infinite recursion.
  if (CAN_RECYCLE(aSize) && !aBase) {
    ret = chunk_recycle(aSize, aAlignment, aZeroed);
  }
  if (!ret) {
    ret = chunk_alloc_mmap(aSize, aAlignment);
    if (aZeroed) {
      *aZeroed = true;
    }
  }
  if (ret && !aBase) {
    if (!gChunkRTree.Set(ret, ret)) {
      chunk_dealloc(ret, aSize, UNKNOWN_CHUNK);
      return nullptr;
    }
  }

  MOZ_ASSERT(GetChunkOffsetForPtr(ret) == 0);
  return ret;
}

static void chunk_ensure_zero(void* aPtr, size_t aSize, bool aZeroed) {
  if (aZeroed == false) {
    memset(aPtr, 0, aSize);
  }
#ifdef MOZ_DEBUG
  else {
    size_t i;
    size_t* p = (size_t*)(uintptr_t)aPtr;

    for (i = 0; i < aSize / sizeof(size_t); i++) {
      MOZ_ASSERT(p[i] == 0);
    }
  }
#endif
}

static void chunk_record(void* aChunk, size_t aSize, ChunkType aType) {
  extent_node_t key;

  if (aType != ZEROED_CHUNK) {
    if (pages_purge(aChunk, aSize, aType == HUGE_CHUNK)) {
      aType = ZEROED_CHUNK;
    }
  }

  // Allocate a node before acquiring chunks_mtx even though it might not
  // be needed, because base_node_alloc() may cause a new base chunk to
  // be allocated, which could cause deadlock if chunks_mtx were already
  // held.
  UniqueBaseNode xnode(base_node_alloc());
  // Use xprev to implement conditional deferred deallocation of prev.
  UniqueBaseNode xprev;

  // RAII deallocates xnode and xprev defined above after unlocking
  // in order to avoid potential dead-locks
  MutexAutoLock lock(chunks_mtx);
  key.mAddr = (void*)((uintptr_t)aChunk + aSize);
  extent_node_t* node = gChunksByAddress.SearchOrNext(&key);
  // Try to coalesce forward.
  if (node && node->mAddr == key.mAddr) {
    // Coalesce chunk with the following address range.  This does
    // not change the position within gChunksByAddress, so only
    // remove/insert from/into gChunksBySize.
    gChunksBySize.Remove(node);
    node->mAddr = aChunk;
    node->mSize += aSize;
    if (node->mChunkType != aType) {
      node->mChunkType = RECYCLED_CHUNK;
    }
    gChunksBySize.Insert(node);
  } else {
    // Coalescing forward failed, so insert a new node.
    if (!xnode) {
      // base_node_alloc() failed, which is an exceedingly
      // unlikely failure.  Leak chunk; its pages have
      // already been purged, so this is only a virtual
      // memory leak.
      return;
    }
    node = xnode.release();
    node->mAddr = aChunk;
    node->mSize = aSize;
    node->mChunkType = aType;
    gChunksByAddress.Insert(node);
    gChunksBySize.Insert(node);
  }

  // Try to coalesce backward.
  extent_node_t* prev = gChunksByAddress.Prev(node);
  if (prev && (void*)((uintptr_t)prev->mAddr + prev->mSize) == aChunk) {
    // Coalesce chunk with the previous address range.  This does
    // not change the position within gChunksByAddress, so only
    // remove/insert node from/into gChunksBySize.
    gChunksBySize.Remove(prev);
    gChunksByAddress.Remove(prev);

    gChunksBySize.Remove(node);
    node->mAddr = prev->mAddr;
    node->mSize += prev->mSize;
    if (node->mChunkType != prev->mChunkType) {
      node->mChunkType = RECYCLED_CHUNK;
    }
    gChunksBySize.Insert(node);

    xprev.reset(prev);
  }

  gRecycledSize += aSize;
}

static void chunk_dealloc(void* aChunk, size_t aSize, ChunkType aType) {
  MOZ_ASSERT(aChunk);
  MOZ_ASSERT(GetChunkOffsetForPtr(aChunk) == 0);
  MOZ_ASSERT(aSize != 0);
  MOZ_ASSERT((aSize & kChunkSizeMask) == 0);

  gChunkRTree.Unset(aChunk);

  if (CAN_RECYCLE(aSize)) {
    size_t recycled_so_far = gRecycledSize;
    // In case some race condition put us above the limit.
    if (recycled_so_far < gRecycleLimit) {
      size_t recycle_remaining = gRecycleLimit - recycled_so_far;
      size_t to_recycle;
      if (aSize > recycle_remaining) {
        to_recycle = recycle_remaining;
        // Drop pages that would overflow the recycle limit
        pages_trim(aChunk, aSize, 0, to_recycle);
      } else {
        to_recycle = aSize;
      }
      chunk_record(aChunk, to_recycle, aType);
      return;
    }
  }

  pages_unmap(aChunk, aSize);
}

#undef CAN_RECYCLE

// End chunk management functions.
// ***************************************************************************
// Begin arena.

static inline arena_t* thread_local_arena(bool enabled) {
  arena_t* arena;

  if (enabled) {
    // The arena will essentially be leaked if this function is
    // called with `false`, but it doesn't matter at the moment.
    // because in practice nothing actually calls this function
    // with `false`, except maybe at shutdown.
    arena =
        gArenas.CreateArena(/* IsPrivate = */ false, /* Params = */ nullptr);
  } else {
    arena = gArenas.GetDefault();
  }
  thread_arena.set(arena);
  return arena;
}

template <>
inline void MozJemalloc::jemalloc_thread_local_arena(bool aEnabled) {
  if (malloc_init()) {
    thread_local_arena(aEnabled);
  }
}

// Choose an arena based on a per-thread value.
static inline arena_t* choose_arena(size_t size) {
  arena_t* ret = nullptr;

  // We can only use TLS if this is a PIC library, since for the static
  // library version, libc's malloc is used by TLS allocation, which
  // introduces a bootstrapping issue.

  if (size > kMaxQuantumClass) {
    // Force the default arena for larger allocations.
    ret = gArenas.GetDefault();
  } else {
    // Check TLS to see if our thread has requested a pinned arena.
    ret = thread_arena.get();
    if (!ret) {
      // Nothing in TLS. Pin this thread to the default arena.
      ret = thread_local_arena(false);
    }
  }

  MOZ_DIAGNOSTIC_ASSERT(ret);
  return ret;
}

static inline void* arena_run_reg_alloc(arena_run_t* run, arena_bin_t* bin) {
  void* ret;
  unsigned i, mask, bit, regind;

  MOZ_DIAGNOSTIC_ASSERT(run->mMagic == ARENA_RUN_MAGIC);
  MOZ_ASSERT(run->mRegionsMinElement < bin->mRunNumRegionsMask);

  // Move the first check outside the loop, so that run->mRegionsMinElement can
  // be updated unconditionally, without the possibility of updating it
  // multiple times.
  i = run->mRegionsMinElement;
  mask = run->mRegionsMask[i];
  if (mask != 0) {
    // Usable allocation found.
    bit = CountTrailingZeroes32(mask);

    regind = ((i << (LOG2(sizeof(int)) + 3)) + bit);
    MOZ_ASSERT(regind < bin->mRunNumRegions);
    ret = (void*)(((uintptr_t)run) + bin->mRunFirstRegionOffset +
                  (bin->mSizeClass * regind));

    // Clear bit.
    mask ^= (1U << bit);
    run->mRegionsMask[i] = mask;

    return ret;
  }

  for (i++; i < bin->mRunNumRegionsMask; i++) {
    mask = run->mRegionsMask[i];
    if (mask != 0) {
      // Usable allocation found.
      bit = CountTrailingZeroes32(mask);

      regind = ((i << (LOG2(sizeof(int)) + 3)) + bit);
      MOZ_ASSERT(regind < bin->mRunNumRegions);
      ret = (void*)(((uintptr_t)run) + bin->mRunFirstRegionOffset +
                    (bin->mSizeClass * regind));

      // Clear bit.
      mask ^= (1U << bit);
      run->mRegionsMask[i] = mask;

      // Make a note that nothing before this element
      // contains a free region.
      run->mRegionsMinElement = i;  // Low payoff: + (mask == 0);

      return ret;
    }
  }
  // Not reached.
  MOZ_DIAGNOSTIC_ASSERT(0);
  return nullptr;
}

static inline void arena_run_reg_dalloc(arena_run_t* run, arena_bin_t* bin,
                                        void* ptr, size_t size) {
// To divide by a number D that is not a power of two we multiply
// by (2^21 / D) and then right shift by 21 positions.
//
//   X / D
//
// becomes
//
//   (X * size_invs[(D / kQuantum) - 3]) >> SIZE_INV_SHIFT

#define SIZE_INV_SHIFT 21
#define SIZE_INV(s) (((1U << SIZE_INV_SHIFT) / (s * kQuantum)) + 1)
  // clang-format off
  static const unsigned size_invs[] = {
    SIZE_INV(3),
    SIZE_INV(4), SIZE_INV(5), SIZE_INV(6), SIZE_INV(7),
    SIZE_INV(8), SIZE_INV(9), SIZE_INV(10), SIZE_INV(11),
    SIZE_INV(12),SIZE_INV(13), SIZE_INV(14), SIZE_INV(15),
    SIZE_INV(16),SIZE_INV(17), SIZE_INV(18), SIZE_INV(19),
    SIZE_INV(20),SIZE_INV(21), SIZE_INV(22), SIZE_INV(23),
    SIZE_INV(24),SIZE_INV(25), SIZE_INV(26), SIZE_INV(27),
    SIZE_INV(28),SIZE_INV(29), SIZE_INV(30), SIZE_INV(31)
  };
  // clang-format on
  unsigned diff, regind, elm, bit;

  MOZ_DIAGNOSTIC_ASSERT(run->mMagic == ARENA_RUN_MAGIC);
  static_assert(
      ((sizeof(size_invs)) / sizeof(unsigned)) + 3 >= kNumQuantumClasses,
      "size_invs doesn't have enough values");

  // Avoid doing division with a variable divisor if possible.  Using
  // actual division here can reduce allocator throughput by over 20%!
  diff =
      (unsigned)((uintptr_t)ptr - (uintptr_t)run - bin->mRunFirstRegionOffset);
  if (mozilla::IsPowerOfTwo(size)) {
    regind = diff >> FloorLog2(size);
  } else if (size <= ((sizeof(size_invs) / sizeof(unsigned)) * kQuantum) + 2) {
    regind = size_invs[(size / kQuantum) - 3] * diff;
    regind >>= SIZE_INV_SHIFT;
  } else {
    // size_invs isn't large enough to handle this size class, so
    // calculate regind using actual division.  This only happens
    // if the user increases small_max via the 'S' runtime
    // configuration option.
    regind = diff / size;
  };
  MOZ_DIAGNOSTIC_ASSERT(diff == regind * size);
  MOZ_DIAGNOSTIC_ASSERT(regind < bin->mRunNumRegions);

  elm = regind >> (LOG2(sizeof(int)) + 3);
  if (elm < run->mRegionsMinElement) {
    run->mRegionsMinElement = elm;
  }
  bit = regind - (elm << (LOG2(sizeof(int)) + 3));
  MOZ_RELEASE_ASSERT((run->mRegionsMask[elm] & (1U << bit)) == 0,
                     "Double-free?");
  run->mRegionsMask[elm] |= (1U << bit);
#undef SIZE_INV
#undef SIZE_INV_SHIFT
}

bool arena_t::SplitRun(arena_run_t* aRun, size_t aSize, bool aLarge,
                       bool aZero) {
  arena_chunk_t* chunk;
  size_t old_ndirty, run_ind, total_pages, need_pages, rem_pages, i;

  chunk = GetChunkForPtr(aRun);
  old_ndirty = chunk->ndirty;
  run_ind = (unsigned)((uintptr_t(aRun) - uintptr_t(chunk)) >> gPageSize2Pow);
  total_pages = (chunk->map[run_ind].bits & ~gPageSizeMask) >> gPageSize2Pow;
  need_pages = (aSize >> gPageSize2Pow);
  MOZ_ASSERT(need_pages > 0);
  MOZ_ASSERT(need_pages <= total_pages);
  rem_pages = total_pages - need_pages;

  for (i = 0; i < need_pages; i++) {
    // Commit decommitted pages if necessary.  If a decommitted
    // page is encountered, commit all needed adjacent decommitted
    // pages in one operation, in order to reduce system call
    // overhead.
    if (chunk->map[run_ind + i].bits & CHUNK_MAP_MADVISED_OR_DECOMMITTED) {
      size_t j;

      // Advance i+j to just past the index of the last page
      // to commit.  Clear CHUNK_MAP_DECOMMITTED and
      // CHUNK_MAP_MADVISED along the way.
      for (j = 0; i + j < need_pages && (chunk->map[run_ind + i + j].bits &
                                         CHUNK_MAP_MADVISED_OR_DECOMMITTED);
           j++) {
        // DECOMMITTED and MADVISED are mutually exclusive.
        MOZ_ASSERT(!(chunk->map[run_ind + i + j].bits & CHUNK_MAP_DECOMMITTED &&
                     chunk->map[run_ind + i + j].bits & CHUNK_MAP_MADVISED));

        chunk->map[run_ind + i + j].bits &= ~CHUNK_MAP_MADVISED_OR_DECOMMITTED;
      }

#ifdef MALLOC_DECOMMIT
      bool committed = pages_commit(
          (void*)(uintptr_t(chunk) + ((run_ind + i) << gPageSize2Pow)),
          j << gPageSize2Pow);
      // pages_commit zeroes pages, so mark them as such if it succeeded.
      // That's checked further below to avoid manually zeroing the pages.
      for (size_t k = 0; k < j; k++) {
        chunk->map[run_ind + i + k].bits |=
            committed ? CHUNK_MAP_ZEROED : CHUNK_MAP_DECOMMITTED;
      }
      if (!committed) {
        return false;
      }
#endif

      mStats.committed += j;
    }
  }

  mRunsAvail.Remove(&chunk->map[run_ind]);

  // Keep track of trailing unused pages for later use.
  if (rem_pages > 0) {
    chunk->map[run_ind + need_pages].bits =
        (rem_pages << gPageSize2Pow) |
        (chunk->map[run_ind + need_pages].bits & gPageSizeMask);
    chunk->map[run_ind + total_pages - 1].bits =
        (rem_pages << gPageSize2Pow) |
        (chunk->map[run_ind + total_pages - 1].bits & gPageSizeMask);
    mRunsAvail.Insert(&chunk->map[run_ind + need_pages]);
  }

  for (i = 0; i < need_pages; i++) {
    // Zero if necessary.
    if (aZero) {
      if ((chunk->map[run_ind + i].bits & CHUNK_MAP_ZEROED) == 0) {
        memset((void*)(uintptr_t(chunk) + ((run_ind + i) << gPageSize2Pow)), 0,
               gPageSize);
        // CHUNK_MAP_ZEROED is cleared below.
      }
    }

    // Update dirty page accounting.
    if (chunk->map[run_ind + i].bits & CHUNK_MAP_DIRTY) {
      chunk->ndirty--;
      mNumDirty--;
      // CHUNK_MAP_DIRTY is cleared below.
    }

    // Initialize the chunk map.
    if (aLarge) {
      chunk->map[run_ind + i].bits = CHUNK_MAP_LARGE | CHUNK_MAP_ALLOCATED;
    } else {
      chunk->map[run_ind + i].bits = size_t(aRun) | CHUNK_MAP_ALLOCATED;
    }
  }

  // Set the run size only in the first element for large runs.  This is
  // primarily a debugging aid, since the lack of size info for trailing
  // pages only matters if the application tries to operate on an
  // interior pointer.
  if (aLarge) {
    chunk->map[run_ind].bits |= aSize;
  }

  if (chunk->ndirty == 0 && old_ndirty > 0) {
    mChunksDirty.Remove(chunk);
  }
  return true;
}

void arena_t::InitChunk(arena_chunk_t* aChunk, bool aZeroed) {
  size_t i;
  // WARNING: The following relies on !aZeroed meaning "used to be an arena
  // chunk".
  // When the chunk we're initializating as an arena chunk is zeroed, we
  // mark all runs are decommitted and zeroed.
  // When it is not, which we can assume means it's a recycled arena chunk,
  // all it can contain is an arena chunk header (which we're overwriting),
  // and zeroed or poisoned memory (because a recycled arena chunk will
  // have been emptied before being recycled). In that case, we can get
  // away with reusing the chunk as-is, marking all runs as madvised.

  size_t flags =
      aZeroed ? CHUNK_MAP_DECOMMITTED | CHUNK_MAP_ZEROED : CHUNK_MAP_MADVISED;

  mStats.mapped += kChunkSize;

  aChunk->arena = this;

  // Claim that no pages are in use, since the header is merely overhead.
  aChunk->ndirty = 0;

  // Initialize the map to contain one maximal free untouched run.
#ifdef MALLOC_DECOMMIT
  arena_run_t* run = (arena_run_t*)(uintptr_t(aChunk) +
                                    (gChunkHeaderNumPages << gPageSize2Pow));
#endif

  for (i = 0; i < gChunkHeaderNumPages; i++) {
    aChunk->map[i].bits = 0;
  }
  aChunk->map[i].bits = gMaxLargeClass | flags;
  for (i++; i < gChunkNumPages - 1; i++) {
    aChunk->map[i].bits = flags;
  }
  aChunk->map[gChunkNumPages - 1].bits = gMaxLargeClass | flags;

#ifdef MALLOC_DECOMMIT
  // Start out decommitted, in order to force a closer correspondence
  // between dirty pages and committed untouched pages.
  pages_decommit(run, gMaxLargeClass);
#endif
  mStats.committed += gChunkHeaderNumPages;

  // Insert the run into the tree of available runs.
  mRunsAvail.Insert(&aChunk->map[gChunkHeaderNumPages]);

#ifdef MALLOC_DOUBLE_PURGE
  new (&aChunk->chunks_madvised_elem) DoublyLinkedListElement<arena_chunk_t>();
#endif
}

void arena_t::DeallocChunk(arena_chunk_t* aChunk) {
  if (mSpare) {
    if (mSpare->ndirty > 0) {
      aChunk->arena->mChunksDirty.Remove(mSpare);
      mNumDirty -= mSpare->ndirty;
      mStats.committed -= mSpare->ndirty;
    }

#ifdef MALLOC_DOUBLE_PURGE
    if (mChunksMAdvised.ElementProbablyInList(mSpare)) {
      mChunksMAdvised.remove(mSpare);
    }
#endif

    chunk_dealloc((void*)mSpare, kChunkSize, ARENA_CHUNK);
    mStats.mapped -= kChunkSize;
    mStats.committed -= gChunkHeaderNumPages;
  }

  // Remove run from the tree of available runs, so that the arena does not use
  // it. Dirty page flushing only uses the tree of dirty chunks, so leaving this
  // chunk in the chunks_* trees is sufficient for that purpose.
  mRunsAvail.Remove(&aChunk->map[gChunkHeaderNumPages]);

  mSpare = aChunk;
}

arena_run_t* arena_t::AllocRun(size_t aSize, bool aLarge, bool aZero) {
  arena_run_t* run;
  arena_chunk_map_t* mapelm;
  arena_chunk_map_t key;

  MOZ_ASSERT(aSize <= gMaxLargeClass);
  MOZ_ASSERT((aSize & gPageSizeMask) == 0);

  // Search the arena's chunks for the lowest best fit.
  key.bits = aSize | CHUNK_MAP_KEY;
  mapelm = mRunsAvail.SearchOrNext(&key);
  if (mapelm) {
    arena_chunk_t* chunk = GetChunkForPtr(mapelm);
    size_t pageind =
        (uintptr_t(mapelm) - uintptr_t(chunk->map)) / sizeof(arena_chunk_map_t);

    run = (arena_run_t*)(uintptr_t(chunk) + (pageind << gPageSize2Pow));
  } else if (mSpare) {
    // Use the spare.
    arena_chunk_t* chunk = mSpare;
    mSpare = nullptr;
    run = (arena_run_t*)(uintptr_t(chunk) +
                         (gChunkHeaderNumPages << gPageSize2Pow));
    // Insert the run into the tree of available runs.
    mRunsAvail.Insert(&chunk->map[gChunkHeaderNumPages]);
  } else {
    // No usable runs.  Create a new chunk from which to allocate
    // the run.
    bool zeroed;
    arena_chunk_t* chunk =
        (arena_chunk_t*)chunk_alloc(kChunkSize, kChunkSize, false, &zeroed);
    if (!chunk) {
      return nullptr;
    }

    InitChunk(chunk, zeroed);
    run = (arena_run_t*)(uintptr_t(chunk) +
                         (gChunkHeaderNumPages << gPageSize2Pow));
  }
  // Update page map.
  return SplitRun(run, aSize, aLarge, aZero) ? run : nullptr;
}

void arena_t::Purge(bool aAll) {
  arena_chunk_t* chunk;
  size_t i, npages;
  // If all is set purge all dirty pages.
  size_t dirty_max = aAll ? 1 : mMaxDirty;
#ifdef MOZ_DEBUG
  size_t ndirty = 0;
  for (auto chunk : mChunksDirty.iter()) {
    ndirty += chunk->ndirty;
  }
  MOZ_ASSERT(ndirty == mNumDirty);
#endif
  MOZ_DIAGNOSTIC_ASSERT(aAll || (mNumDirty > mMaxDirty));

  // Iterate downward through chunks until enough dirty memory has been
  // purged.  Terminate as soon as possible in order to minimize the
  // number of system calls, even if a chunk has only been partially
  // purged.
  while (mNumDirty > (dirty_max >> 1)) {
#ifdef MALLOC_DOUBLE_PURGE
    bool madvised = false;
#endif
    chunk = mChunksDirty.Last();
    MOZ_DIAGNOSTIC_ASSERT(chunk);

    for (i = gChunkNumPages - 1; chunk->ndirty > 0; i--) {
      MOZ_DIAGNOSTIC_ASSERT(i >= gChunkHeaderNumPages);

      if (chunk->map[i].bits & CHUNK_MAP_DIRTY) {
#ifdef MALLOC_DECOMMIT
        const size_t free_operation = CHUNK_MAP_DECOMMITTED;
#else
        const size_t free_operation = CHUNK_MAP_MADVISED;
#endif
        MOZ_ASSERT((chunk->map[i].bits & CHUNK_MAP_MADVISED_OR_DECOMMITTED) ==
                   0);
        chunk->map[i].bits ^= free_operation | CHUNK_MAP_DIRTY;
        // Find adjacent dirty run(s).
        for (npages = 1; i > gChunkHeaderNumPages &&
                         (chunk->map[i - 1].bits & CHUNK_MAP_DIRTY);
             npages++) {
          i--;