rocksdb/util/crc32c.cc
Abhishek Kona d29f181923 Fix all the lint errors.
Summary:
Scripted and removed all trailing spaces and converted all tabs to
spaces.

Also fixed other lint errors.
All lint errors from this point of time should be taken seriously.

Test Plan: make all check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7059
2012-11-28 17:18:41 -08:00

351 lines
15 KiB
C++

// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
//
// A portable implementation of crc32c, optimized to handle
// four bytes at a time.
#include "util/crc32c.h"
#ifdef __SSE4_2__
#include <nmmintrin.h>
#endif
#include <stdint.h>
#include "util/coding.h"
namespace leveldb {
namespace crc32c {
static const uint32_t table0_[256] = {
0x00000000, 0xf26b8303, 0xe13b70f7, 0x1350f3f4,
0xc79a971f, 0x35f1141c, 0x26a1e7e8, 0xd4ca64eb,
0x8ad958cf, 0x78b2dbcc, 0x6be22838, 0x9989ab3b,
0x4d43cfd0, 0xbf284cd3, 0xac78bf27, 0x5e133c24,
0x105ec76f, 0xe235446c, 0xf165b798, 0x030e349b,
0xd7c45070, 0x25afd373, 0x36ff2087, 0xc494a384,
0x9a879fa0, 0x68ec1ca3, 0x7bbcef57, 0x89d76c54,
0x5d1d08bf, 0xaf768bbc, 0xbc267848, 0x4e4dfb4b,
0x20bd8ede, 0xd2d60ddd, 0xc186fe29, 0x33ed7d2a,
0xe72719c1, 0x154c9ac2, 0x061c6936, 0xf477ea35,
0xaa64d611, 0x580f5512, 0x4b5fa6e6, 0xb93425e5,
0x6dfe410e, 0x9f95c20d, 0x8cc531f9, 0x7eaeb2fa,
0x30e349b1, 0xc288cab2, 0xd1d83946, 0x23b3ba45,
0xf779deae, 0x05125dad, 0x1642ae59, 0xe4292d5a,
0xba3a117e, 0x4851927d, 0x5b016189, 0xa96ae28a,
0x7da08661, 0x8fcb0562, 0x9c9bf696, 0x6ef07595,
0x417b1dbc, 0xb3109ebf, 0xa0406d4b, 0x522bee48,
0x86e18aa3, 0x748a09a0, 0x67dafa54, 0x95b17957,
0xcba24573, 0x39c9c670, 0x2a993584, 0xd8f2b687,
0x0c38d26c, 0xfe53516f, 0xed03a29b, 0x1f682198,
0x5125dad3, 0xa34e59d0, 0xb01eaa24, 0x42752927,
0x96bf4dcc, 0x64d4cecf, 0x77843d3b, 0x85efbe38,
0xdbfc821c, 0x2997011f, 0x3ac7f2eb, 0xc8ac71e8,
0x1c661503, 0xee0d9600, 0xfd5d65f4, 0x0f36e6f7,
0x61c69362, 0x93ad1061, 0x80fde395, 0x72966096,
0xa65c047d, 0x5437877e, 0x4767748a, 0xb50cf789,
0xeb1fcbad, 0x197448ae, 0x0a24bb5a, 0xf84f3859,
0x2c855cb2, 0xdeeedfb1, 0xcdbe2c45, 0x3fd5af46,
0x7198540d, 0x83f3d70e, 0x90a324fa, 0x62c8a7f9,
0xb602c312, 0x44694011, 0x5739b3e5, 0xa55230e6,
0xfb410cc2, 0x092a8fc1, 0x1a7a7c35, 0xe811ff36,
0x3cdb9bdd, 0xceb018de, 0xdde0eb2a, 0x2f8b6829,
0x82f63b78, 0x709db87b, 0x63cd4b8f, 0x91a6c88c,
0x456cac67, 0xb7072f64, 0xa457dc90, 0x563c5f93,
0x082f63b7, 0xfa44e0b4, 0xe9141340, 0x1b7f9043,
0xcfb5f4a8, 0x3dde77ab, 0x2e8e845f, 0xdce5075c,
0x92a8fc17, 0x60c37f14, 0x73938ce0, 0x81f80fe3,
0x55326b08, 0xa759e80b, 0xb4091bff, 0x466298fc,
0x1871a4d8, 0xea1a27db, 0xf94ad42f, 0x0b21572c,
0xdfeb33c7, 0x2d80b0c4, 0x3ed04330, 0xccbbc033,
0xa24bb5a6, 0x502036a5, 0x4370c551, 0xb11b4652,
0x65d122b9, 0x97baa1ba, 0x84ea524e, 0x7681d14d,
0x2892ed69, 0xdaf96e6a, 0xc9a99d9e, 0x3bc21e9d,
0xef087a76, 0x1d63f975, 0x0e330a81, 0xfc588982,
0xb21572c9, 0x407ef1ca, 0x532e023e, 0xa145813d,
0x758fe5d6, 0x87e466d5, 0x94b49521, 0x66df1622,
0x38cc2a06, 0xcaa7a905, 0xd9f75af1, 0x2b9cd9f2,
0xff56bd19, 0x0d3d3e1a, 0x1e6dcdee, 0xec064eed,
0xc38d26c4, 0x31e6a5c7, 0x22b65633, 0xd0ddd530,
0x0417b1db, 0xf67c32d8, 0xe52cc12c, 0x1747422f,
0x49547e0b, 0xbb3ffd08, 0xa86f0efc, 0x5a048dff,
0x8ecee914, 0x7ca56a17, 0x6ff599e3, 0x9d9e1ae0,
0xd3d3e1ab, 0x21b862a8, 0x32e8915c, 0xc083125f,
0x144976b4, 0xe622f5b7, 0xf5720643, 0x07198540,
0x590ab964, 0xab613a67, 0xb831c993, 0x4a5a4a90,
0x9e902e7b, 0x6cfbad78, 0x7fab5e8c, 0x8dc0dd8f,
0xe330a81a, 0x115b2b19, 0x020bd8ed, 0xf0605bee,
0x24aa3f05, 0xd6c1bc06, 0xc5914ff2, 0x37faccf1,
0x69e9f0d5, 0x9b8273d6, 0x88d28022, 0x7ab90321,
0xae7367ca, 0x5c18e4c9, 0x4f48173d, 0xbd23943e,
0xf36e6f75, 0x0105ec76, 0x12551f82, 0xe03e9c81,
0x34f4f86a, 0xc69f7b69, 0xd5cf889d, 0x27a40b9e,
0x79b737ba, 0x8bdcb4b9, 0x988c474d, 0x6ae7c44e,
0xbe2da0a5, 0x4c4623a6, 0x5f16d052, 0xad7d5351
};
static const uint32_t table1_[256] = {
0x00000000, 0x13a29877, 0x274530ee, 0x34e7a899,
0x4e8a61dc, 0x5d28f9ab, 0x69cf5132, 0x7a6dc945,
0x9d14c3b8, 0x8eb65bcf, 0xba51f356, 0xa9f36b21,
0xd39ea264, 0xc03c3a13, 0xf4db928a, 0xe7790afd,
0x3fc5f181, 0x2c6769f6, 0x1880c16f, 0x0b225918,
0x714f905d, 0x62ed082a, 0x560aa0b3, 0x45a838c4,
0xa2d13239, 0xb173aa4e, 0x859402d7, 0x96369aa0,
0xec5b53e5, 0xfff9cb92, 0xcb1e630b, 0xd8bcfb7c,
0x7f8be302, 0x6c297b75, 0x58ced3ec, 0x4b6c4b9b,
0x310182de, 0x22a31aa9, 0x1644b230, 0x05e62a47,
0xe29f20ba, 0xf13db8cd, 0xc5da1054, 0xd6788823,
0xac154166, 0xbfb7d911, 0x8b507188, 0x98f2e9ff,
0x404e1283, 0x53ec8af4, 0x670b226d, 0x74a9ba1a,
0x0ec4735f, 0x1d66eb28, 0x298143b1, 0x3a23dbc6,
0xdd5ad13b, 0xcef8494c, 0xfa1fe1d5, 0xe9bd79a2,
0x93d0b0e7, 0x80722890, 0xb4958009, 0xa737187e,
0xff17c604, 0xecb55e73, 0xd852f6ea, 0xcbf06e9d,
0xb19da7d8, 0xa23f3faf, 0x96d89736, 0x857a0f41,
0x620305bc, 0x71a19dcb, 0x45463552, 0x56e4ad25,
0x2c896460, 0x3f2bfc17, 0x0bcc548e, 0x186eccf9,
0xc0d23785, 0xd370aff2, 0xe797076b, 0xf4359f1c,
0x8e585659, 0x9dface2e, 0xa91d66b7, 0xbabffec0,
0x5dc6f43d, 0x4e646c4a, 0x7a83c4d3, 0x69215ca4,
0x134c95e1, 0x00ee0d96, 0x3409a50f, 0x27ab3d78,
0x809c2506, 0x933ebd71, 0xa7d915e8, 0xb47b8d9f,
0xce1644da, 0xddb4dcad, 0xe9537434, 0xfaf1ec43,
0x1d88e6be, 0x0e2a7ec9, 0x3acdd650, 0x296f4e27,
0x53028762, 0x40a01f15, 0x7447b78c, 0x67e52ffb,
0xbf59d487, 0xacfb4cf0, 0x981ce469, 0x8bbe7c1e,
0xf1d3b55b, 0xe2712d2c, 0xd69685b5, 0xc5341dc2,
0x224d173f, 0x31ef8f48, 0x050827d1, 0x16aabfa6,
0x6cc776e3, 0x7f65ee94, 0x4b82460d, 0x5820de7a,
0xfbc3faf9, 0xe861628e, 0xdc86ca17, 0xcf245260,
0xb5499b25, 0xa6eb0352, 0x920cabcb, 0x81ae33bc,
0x66d73941, 0x7575a136, 0x419209af, 0x523091d8,
0x285d589d, 0x3bffc0ea, 0x0f186873, 0x1cbaf004,
0xc4060b78, 0xd7a4930f, 0xe3433b96, 0xf0e1a3e1,
0x8a8c6aa4, 0x992ef2d3, 0xadc95a4a, 0xbe6bc23d,
0x5912c8c0, 0x4ab050b7, 0x7e57f82e, 0x6df56059,
0x1798a91c, 0x043a316b, 0x30dd99f2, 0x237f0185,
0x844819fb, 0x97ea818c, 0xa30d2915, 0xb0afb162,
0xcac27827, 0xd960e050, 0xed8748c9, 0xfe25d0be,
0x195cda43, 0x0afe4234, 0x3e19eaad, 0x2dbb72da,
0x57d6bb9f, 0x447423e8, 0x70938b71, 0x63311306,
0xbb8de87a, 0xa82f700d, 0x9cc8d894, 0x8f6a40e3,
0xf50789a6, 0xe6a511d1, 0xd242b948, 0xc1e0213f,
0x26992bc2, 0x353bb3b5, 0x01dc1b2c, 0x127e835b,
0x68134a1e, 0x7bb1d269, 0x4f567af0, 0x5cf4e287,
0x04d43cfd, 0x1776a48a, 0x23910c13, 0x30339464,
0x4a5e5d21, 0x59fcc556, 0x6d1b6dcf, 0x7eb9f5b8,
0x99c0ff45, 0x8a626732, 0xbe85cfab, 0xad2757dc,
0xd74a9e99, 0xc4e806ee, 0xf00fae77, 0xe3ad3600,
0x3b11cd7c, 0x28b3550b, 0x1c54fd92, 0x0ff665e5,
0x759baca0, 0x663934d7, 0x52de9c4e, 0x417c0439,
0xa6050ec4, 0xb5a796b3, 0x81403e2a, 0x92e2a65d,
0xe88f6f18, 0xfb2df76f, 0xcfca5ff6, 0xdc68c781,
0x7b5fdfff, 0x68fd4788, 0x5c1aef11, 0x4fb87766,
0x35d5be23, 0x26772654, 0x12908ecd, 0x013216ba,
0xe64b1c47, 0xf5e98430, 0xc10e2ca9, 0xd2acb4de,
0xa8c17d9b, 0xbb63e5ec, 0x8f844d75, 0x9c26d502,
0x449a2e7e, 0x5738b609, 0x63df1e90, 0x707d86e7,
0x0a104fa2, 0x19b2d7d5, 0x2d557f4c, 0x3ef7e73b,
0xd98eedc6, 0xca2c75b1, 0xfecbdd28, 0xed69455f,
0x97048c1a, 0x84a6146d, 0xb041bcf4, 0xa3e32483
};
static const uint32_t table2_[256] = {
0x00000000, 0xa541927e, 0x4f6f520d, 0xea2ec073,
0x9edea41a, 0x3b9f3664, 0xd1b1f617, 0x74f06469,
0x38513ec5, 0x9d10acbb, 0x773e6cc8, 0xd27ffeb6,
0xa68f9adf, 0x03ce08a1, 0xe9e0c8d2, 0x4ca15aac,
0x70a27d8a, 0xd5e3eff4, 0x3fcd2f87, 0x9a8cbdf9,
0xee7cd990, 0x4b3d4bee, 0xa1138b9d, 0x045219e3,
0x48f3434f, 0xedb2d131, 0x079c1142, 0xa2dd833c,
0xd62de755, 0x736c752b, 0x9942b558, 0x3c032726,
0xe144fb14, 0x4405696a, 0xae2ba919, 0x0b6a3b67,
0x7f9a5f0e, 0xdadbcd70, 0x30f50d03, 0x95b49f7d,
0xd915c5d1, 0x7c5457af, 0x967a97dc, 0x333b05a2,
0x47cb61cb, 0xe28af3b5, 0x08a433c6, 0xade5a1b8,
0x91e6869e, 0x34a714e0, 0xde89d493, 0x7bc846ed,
0x0f382284, 0xaa79b0fa, 0x40577089, 0xe516e2f7,
0xa9b7b85b, 0x0cf62a25, 0xe6d8ea56, 0x43997828,
0x37691c41, 0x92288e3f, 0x78064e4c, 0xdd47dc32,
0xc76580d9, 0x622412a7, 0x880ad2d4, 0x2d4b40aa,
0x59bb24c3, 0xfcfab6bd, 0x16d476ce, 0xb395e4b0,
0xff34be1c, 0x5a752c62, 0xb05bec11, 0x151a7e6f,
0x61ea1a06, 0xc4ab8878, 0x2e85480b, 0x8bc4da75,
0xb7c7fd53, 0x12866f2d, 0xf8a8af5e, 0x5de93d20,
0x29195949, 0x8c58cb37, 0x66760b44, 0xc337993a,
0x8f96c396, 0x2ad751e8, 0xc0f9919b, 0x65b803e5,
0x1148678c, 0xb409f5f2, 0x5e273581, 0xfb66a7ff,
0x26217bcd, 0x8360e9b3, 0x694e29c0, 0xcc0fbbbe,
0xb8ffdfd7, 0x1dbe4da9, 0xf7908dda, 0x52d11fa4,
0x1e704508, 0xbb31d776, 0x511f1705, 0xf45e857b,
0x80aee112, 0x25ef736c, 0xcfc1b31f, 0x6a802161,
0x56830647, 0xf3c29439, 0x19ec544a, 0xbcadc634,
0xc85da25d, 0x6d1c3023, 0x8732f050, 0x2273622e,
0x6ed23882, 0xcb93aafc, 0x21bd6a8f, 0x84fcf8f1,
0xf00c9c98, 0x554d0ee6, 0xbf63ce95, 0x1a225ceb,
0x8b277743, 0x2e66e53d, 0xc448254e, 0x6109b730,
0x15f9d359, 0xb0b84127, 0x5a968154, 0xffd7132a,
0xb3764986, 0x1637dbf8, 0xfc191b8b, 0x595889f5,
0x2da8ed9c, 0x88e97fe2, 0x62c7bf91, 0xc7862def,
0xfb850ac9, 0x5ec498b7, 0xb4ea58c4, 0x11abcaba,
0x655baed3, 0xc01a3cad, 0x2a34fcde, 0x8f756ea0,
0xc3d4340c, 0x6695a672, 0x8cbb6601, 0x29faf47f,
0x5d0a9016, 0xf84b0268, 0x1265c21b, 0xb7245065,
0x6a638c57, 0xcf221e29, 0x250cde5a, 0x804d4c24,
0xf4bd284d, 0x51fcba33, 0xbbd27a40, 0x1e93e83e,
0x5232b292, 0xf77320ec, 0x1d5de09f, 0xb81c72e1,
0xccec1688, 0x69ad84f6, 0x83834485, 0x26c2d6fb,
0x1ac1f1dd, 0xbf8063a3, 0x55aea3d0, 0xf0ef31ae,
0x841f55c7, 0x215ec7b9, 0xcb7007ca, 0x6e3195b4,
0x2290cf18, 0x87d15d66, 0x6dff9d15, 0xc8be0f6b,
0xbc4e6b02, 0x190ff97c, 0xf321390f, 0x5660ab71,
0x4c42f79a, 0xe90365e4, 0x032da597, 0xa66c37e9,
0xd29c5380, 0x77ddc1fe, 0x9df3018d, 0x38b293f3,
0x7413c95f, 0xd1525b21, 0x3b7c9b52, 0x9e3d092c,
0xeacd6d45, 0x4f8cff3b, 0xa5a23f48, 0x00e3ad36,
0x3ce08a10, 0x99a1186e, 0x738fd81d, 0xd6ce4a63,
0xa23e2e0a, 0x077fbc74, 0xed517c07, 0x4810ee79,
0x04b1b4d5, 0xa1f026ab, 0x4bdee6d8, 0xee9f74a6,
0x9a6f10cf, 0x3f2e82b1, 0xd50042c2, 0x7041d0bc,
0xad060c8e, 0x08479ef0, 0xe2695e83, 0x4728ccfd,
0x33d8a894, 0x96993aea, 0x7cb7fa99, 0xd9f668e7,
0x9557324b, 0x3016a035, 0xda386046, 0x7f79f238,
0x0b899651, 0xaec8042f, 0x44e6c45c, 0xe1a75622,
0xdda47104, 0x78e5e37a, 0x92cb2309, 0x378ab177,
0x437ad51e, 0xe63b4760, 0x0c158713, 0xa954156d,
0xe5f54fc1, 0x40b4ddbf, 0xaa9a1dcc, 0x0fdb8fb2,
0x7b2bebdb, 0xde6a79a5, 0x3444b9d6, 0x91052ba8
};
static const uint32_t table3_[256] = {
0x00000000, 0xdd45aab8, 0xbf672381, 0x62228939,
0x7b2231f3, 0xa6679b4b, 0xc4451272, 0x1900b8ca,
0xf64463e6, 0x2b01c95e, 0x49234067, 0x9466eadf,
0x8d665215, 0x5023f8ad, 0x32017194, 0xef44db2c,
0xe964b13d, 0x34211b85, 0x560392bc, 0x8b463804,
0x924680ce, 0x4f032a76, 0x2d21a34f, 0xf06409f7,
0x1f20d2db, 0xc2657863, 0xa047f15a, 0x7d025be2,
0x6402e328, 0xb9474990, 0xdb65c0a9, 0x06206a11,
0xd725148b, 0x0a60be33, 0x6842370a, 0xb5079db2,
0xac072578, 0x71428fc0, 0x136006f9, 0xce25ac41,
0x2161776d, 0xfc24ddd5, 0x9e0654ec, 0x4343fe54,
0x5a43469e, 0x8706ec26, 0xe524651f, 0x3861cfa7,
0x3e41a5b6, 0xe3040f0e, 0x81268637, 0x5c632c8f,
0x45639445, 0x98263efd, 0xfa04b7c4, 0x27411d7c,
0xc805c650, 0x15406ce8, 0x7762e5d1, 0xaa274f69,
0xb327f7a3, 0x6e625d1b, 0x0c40d422, 0xd1057e9a,
0xaba65fe7, 0x76e3f55f, 0x14c17c66, 0xc984d6de,
0xd0846e14, 0x0dc1c4ac, 0x6fe34d95, 0xb2a6e72d,
0x5de23c01, 0x80a796b9, 0xe2851f80, 0x3fc0b538,
0x26c00df2, 0xfb85a74a, 0x99a72e73, 0x44e284cb,
0x42c2eeda, 0x9f874462, 0xfda5cd5b, 0x20e067e3,
0x39e0df29, 0xe4a57591, 0x8687fca8, 0x5bc25610,
0xb4868d3c, 0x69c32784, 0x0be1aebd, 0xd6a40405,
0xcfa4bccf, 0x12e11677, 0x70c39f4e, 0xad8635f6,
0x7c834b6c, 0xa1c6e1d4, 0xc3e468ed, 0x1ea1c255,
0x07a17a9f, 0xdae4d027, 0xb8c6591e, 0x6583f3a6,
0x8ac7288a, 0x57828232, 0x35a00b0b, 0xe8e5a1b3,
0xf1e51979, 0x2ca0b3c1, 0x4e823af8, 0x93c79040,
0x95e7fa51, 0x48a250e9, 0x2a80d9d0, 0xf7c57368,
0xeec5cba2, 0x3380611a, 0x51a2e823, 0x8ce7429b,
0x63a399b7, 0xbee6330f, 0xdcc4ba36, 0x0181108e,
0x1881a844, 0xc5c402fc, 0xa7e68bc5, 0x7aa3217d,
0x52a0c93f, 0x8fe56387, 0xedc7eabe, 0x30824006,
0x2982f8cc, 0xf4c75274, 0x96e5db4d, 0x4ba071f5,
0xa4e4aad9, 0x79a10061, 0x1b838958, 0xc6c623e0,
0xdfc69b2a, 0x02833192, 0x60a1b8ab, 0xbde41213,
0xbbc47802, 0x6681d2ba, 0x04a35b83, 0xd9e6f13b,
0xc0e649f1, 0x1da3e349, 0x7f816a70, 0xa2c4c0c8,
0x4d801be4, 0x90c5b15c, 0xf2e73865, 0x2fa292dd,
0x36a22a17, 0xebe780af, 0x89c50996, 0x5480a32e,
0x8585ddb4, 0x58c0770c, 0x3ae2fe35, 0xe7a7548d,
0xfea7ec47, 0x23e246ff, 0x41c0cfc6, 0x9c85657e,
0x73c1be52, 0xae8414ea, 0xcca69dd3, 0x11e3376b,
0x08e38fa1, 0xd5a62519, 0xb784ac20, 0x6ac10698,
0x6ce16c89, 0xb1a4c631, 0xd3864f08, 0x0ec3e5b0,
0x17c35d7a, 0xca86f7c2, 0xa8a47efb, 0x75e1d443,
0x9aa50f6f, 0x47e0a5d7, 0x25c22cee, 0xf8878656,
0xe1873e9c, 0x3cc29424, 0x5ee01d1d, 0x83a5b7a5,
0xf90696d8, 0x24433c60, 0x4661b559, 0x9b241fe1,
0x8224a72b, 0x5f610d93, 0x3d4384aa, 0xe0062e12,
0x0f42f53e, 0xd2075f86, 0xb025d6bf, 0x6d607c07,
0x7460c4cd, 0xa9256e75, 0xcb07e74c, 0x16424df4,
0x106227e5, 0xcd278d5d, 0xaf050464, 0x7240aedc,
0x6b401616, 0xb605bcae, 0xd4273597, 0x09629f2f,
0xe6264403, 0x3b63eebb, 0x59416782, 0x8404cd3a,
0x9d0475f0, 0x4041df48, 0x22635671, 0xff26fcc9,
0x2e238253, 0xf36628eb, 0x9144a1d2, 0x4c010b6a,
0x5501b3a0, 0x88441918, 0xea669021, 0x37233a99,
0xd867e1b5, 0x05224b0d, 0x6700c234, 0xba45688c,
0xa345d046, 0x7e007afe, 0x1c22f3c7, 0xc167597f,
0xc747336e, 0x1a0299d6, 0x782010ef, 0xa565ba57,
0xbc65029d, 0x6120a825, 0x0302211c, 0xde478ba4,
0x31035088, 0xec46fa30, 0x8e647309, 0x5321d9b1,
0x4a21617b, 0x9764cbc3, 0xf54642fa, 0x2803e842
};
// Used to fetch a naturally-aligned 32-bit word in little endian byte-order
static inline uint32_t LE_LOAD32(const uint8_t *p) {
return DecodeFixed32(reinterpret_cast<const char*>(p));
}
static inline uint64_t LE_LOAD64(const uint8_t *p) {
return DecodeFixed64(reinterpret_cast<const char*>(p));
}
uint32_t Extend(uint32_t crc, const char* buf, size_t size) {
const uint8_t *p = reinterpret_cast<const uint8_t *>(buf);
const uint8_t *e = p + size;
uint64_t l = crc ^ 0xffffffffu;
// Align n to (1 << m) byte boundary
#define ALIGN(n, m) ((n + ((1 << m) - 1)) & ~((1 << m) - 1))
#define STEP1 do { \
int c = (l & 0xff) ^ *p++; \
l = table0_[c] ^ (l >> 8); \
} while (0)
#define STEP4 do { \
uint32_t c = l ^ LE_LOAD32(p); \
p += 4; \
l = table3_[c & 0xff] ^ \
table2_[(c >> 8) & 0xff] ^ \
table1_[(c >> 16) & 0xff] ^ \
table0_[c >> 24]; \
} while (0)
#ifdef __SSE4_2__
#define STEP8 do { l = _mm_crc32_u64(l, LE_LOAD64(p)); p += 8; } while(0)
#else
#define STEP8 do { STEP4; STEP4; } while(0)
#endif
// Point x at first 16-byte aligned byte in string. This might be
// just past the end of the string.
const uintptr_t pval = reinterpret_cast<uintptr_t>(p);
const uint8_t* x = reinterpret_cast<const uint8_t*>(ALIGN(pval, 4));
if (x <= e) {
// Process bytes until finished or p is 16-byte aligned
while (p != x) {
STEP1;
}
}
// Process bytes 16 at a time
while ((e-p) >= 16) {
STEP8; STEP8;
}
// Process bytes 8 at a time
while ((e-p) >= 8) {
STEP8;
}
// Process the last few bytes
while (p != e) {
STEP1;
}
#undef STEP8
#undef STEP4
#undef STEP1
#undef ALIGN
return l ^ 0xffffffffu;
}
} // namespace crc32c
} // namespace leveldb