aboutsummaryrefslogtreecommitdiff
path: root/third_party/crc32c/src/src/crc32c_sse42.cc
blob: fc0cb0725f8da043bf351754a8d1d9cec42e4f1b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
// Copyright 2008 The CRC32C 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.

#include "./crc32c_sse42.h"

// In a separate source file to allow this accelerated CRC32C function to be
// compiled with the appropriate compiler flags to enable SSE4.2 instructions.

// This implementation is loosely based on Intel Pub 323405 from April 2011,
// "Fast CRC Computation for iSCSI Polynomial Using CRC32 Instruction".

#include <cstddef>
#include <cstdint>

#include "./crc32c_internal.h"
#include "./crc32c_prefetch.h"
#include "./crc32c_read_le.h"
#include "./crc32c_round_up.h"
#include "crc32c/crc32c_config.h"

#if HAVE_SSE42 && (defined(_M_X64) || defined(__x86_64__))

#if defined(_MSC_VER)
#include <intrin.h>
#else  // !defined(_MSC_VER)
#include <nmmintrin.h>
#endif  // defined(_MSC_VER)

namespace crc32c {

namespace {

constexpr const ptrdiff_t kGroups = 3;
constexpr const ptrdiff_t kBlock0Size = 16 * 1024 / kGroups / 64 * 64;
constexpr const ptrdiff_t kBlock1Size = 4 * 1024 / kGroups / 8 * 8;
constexpr const ptrdiff_t kBlock2Size = 1024 / kGroups / 8 * 8;

const uint32_t kBlock0SkipTable[8][16] = {
    {0x00000000, 0xff770459, 0xfb027e43, 0x04757a1a, 0xf3e88a77, 0x0c9f8e2e,
     0x08eaf434, 0xf79df06d, 0xe23d621f, 0x1d4a6646, 0x193f1c5c, 0xe6481805,
     0x11d5e868, 0xeea2ec31, 0xead7962b, 0x15a09272},
    {0x00000000, 0xc196b2cf, 0x86c1136f, 0x4757a1a0, 0x086e502f, 0xc9f8e2e0,
     0x8eaf4340, 0x4f39f18f, 0x10dca05e, 0xd14a1291, 0x961db331, 0x578b01fe,
     0x18b2f071, 0xd92442be, 0x9e73e31e, 0x5fe551d1},
    {0x00000000, 0x21b940bc, 0x43728178, 0x62cbc1c4, 0x86e502f0, 0xa75c424c,
     0xc5978388, 0xe42ec334, 0x08267311, 0x299f33ad, 0x4b54f269, 0x6aedb2d5,
     0x8ec371e1, 0xaf7a315d, 0xcdb1f099, 0xec08b025},
    {0x00000000, 0x104ce622, 0x2099cc44, 0x30d52a66, 0x41339888, 0x517f7eaa,
     0x61aa54cc, 0x71e6b2ee, 0x82673110, 0x922bd732, 0xa2fefd54, 0xb2b21b76,
     0xc354a998, 0xd3184fba, 0xe3cd65dc, 0xf38183fe},
    {0x00000000, 0x012214d1, 0x024429a2, 0x03663d73, 0x04885344, 0x05aa4795,
     0x06cc7ae6, 0x07ee6e37, 0x0910a688, 0x0832b259, 0x0b548f2a, 0x0a769bfb,
     0x0d98f5cc, 0x0cbae11d, 0x0fdcdc6e, 0x0efec8bf},
    {0x00000000, 0x12214d10, 0x24429a20, 0x3663d730, 0x48853440, 0x5aa47950,
     0x6cc7ae60, 0x7ee6e370, 0x910a6880, 0x832b2590, 0xb548f2a0, 0xa769bfb0,
     0xd98f5cc0, 0xcbae11d0, 0xfdcdc6e0, 0xefec8bf0},
    {0x00000000, 0x27f8a7f1, 0x4ff14fe2, 0x6809e813, 0x9fe29fc4, 0xb81a3835,
     0xd013d026, 0xf7eb77d7, 0x3a294979, 0x1dd1ee88, 0x75d8069b, 0x5220a16a,
     0xa5cbd6bd, 0x8233714c, 0xea3a995f, 0xcdc23eae},
    {0x00000000, 0x745292f2, 0xe8a525e4, 0x9cf7b716, 0xd4a63d39, 0xa0f4afcb,
     0x3c0318dd, 0x48518a2f, 0xaca00c83, 0xd8f29e71, 0x44052967, 0x3057bb95,
     0x780631ba, 0x0c54a348, 0x90a3145e, 0xe4f186ac},
};
const uint32_t kBlock1SkipTable[8][16] = {
    {0x00000000, 0x79113270, 0xf22264e0, 0x8b335690, 0xe1a8bf31, 0x98b98d41,
     0x138adbd1, 0x6a9be9a1, 0xc6bd0893, 0xbfac3ae3, 0x349f6c73, 0x4d8e5e03,
     0x2715b7a2, 0x5e0485d2, 0xd537d342, 0xac26e132},
    {0x00000000, 0x889667d7, 0x14c0b95f, 0x9c56de88, 0x298172be, 0xa1171569,
     0x3d41cbe1, 0xb5d7ac36, 0x5302e57c, 0xdb9482ab, 0x47c25c23, 0xcf543bf4,
     0x7a8397c2, 0xf215f015, 0x6e432e9d, 0xe6d5494a},
    {0x00000000, 0xa605caf8, 0x49e7e301, 0xefe229f9, 0x93cfc602, 0x35ca0cfa,
     0xda282503, 0x7c2deffb, 0x2273faf5, 0x8476300d, 0x6b9419f4, 0xcd91d30c,
     0xb1bc3cf7, 0x17b9f60f, 0xf85bdff6, 0x5e5e150e},
    {0x00000000, 0x44e7f5ea, 0x89cfebd4, 0xcd281e3e, 0x1673a159, 0x529454b3,
     0x9fbc4a8d, 0xdb5bbf67, 0x2ce742b2, 0x6800b758, 0xa528a966, 0xe1cf5c8c,
     0x3a94e3eb, 0x7e731601, 0xb35b083f, 0xf7bcfdd5},
    {0x00000000, 0x59ce8564, 0xb39d0ac8, 0xea538fac, 0x62d66361, 0x3b18e605,
     0xd14b69a9, 0x8885eccd, 0xc5acc6c2, 0x9c6243a6, 0x7631cc0a, 0x2fff496e,
     0xa77aa5a3, 0xfeb420c7, 0x14e7af6b, 0x4d292a0f},
    {0x00000000, 0x8eb5fb75, 0x1887801b, 0x96327b6e, 0x310f0036, 0xbfbafb43,
     0x2988802d, 0xa73d7b58, 0x621e006c, 0xecabfb19, 0x7a998077, 0xf42c7b02,
     0x5311005a, 0xdda4fb2f, 0x4b968041, 0xc5237b34},
    {0x00000000, 0xc43c00d8, 0x8d947741, 0x49a87799, 0x1ec49873, 0xdaf898ab,
     0x9350ef32, 0x576cefea, 0x3d8930e6, 0xf9b5303e, 0xb01d47a7, 0x7421477f,
     0x234da895, 0xe771a84d, 0xaed9dfd4, 0x6ae5df0c},
    {0x00000000, 0x7b1261cc, 0xf624c398, 0x8d36a254, 0xe9a5f1c1, 0x92b7900d,
     0x1f813259, 0x64935395, 0xd6a79573, 0xadb5f4bf, 0x208356eb, 0x5b913727,
     0x3f0264b2, 0x4410057e, 0xc926a72a, 0xb234c6e6},
};
const uint32_t kBlock2SkipTable[8][16] = {
    {0x00000000, 0x8f158014, 0x1bc776d9, 0x94d2f6cd, 0x378eedb2, 0xb89b6da6,
     0x2c499b6b, 0xa35c1b7f, 0x6f1ddb64, 0xe0085b70, 0x74daadbd, 0xfbcf2da9,
     0x589336d6, 0xd786b6c2, 0x4354400f, 0xcc41c01b},
    {0x00000000, 0xde3bb6c8, 0xb99b1b61, 0x67a0ada9, 0x76da4033, 0xa8e1f6fb,
     0xcf415b52, 0x117aed9a, 0xedb48066, 0x338f36ae, 0x542f9b07, 0x8a142dcf,
     0x9b6ec055, 0x4555769d, 0x22f5db34, 0xfcce6dfc},
    {0x00000000, 0xde85763d, 0xb8e69a8b, 0x6663ecb6, 0x742143e7, 0xaaa435da,
     0xccc7d96c, 0x1242af51, 0xe84287ce, 0x36c7f1f3, 0x50a41d45, 0x8e216b78,
     0x9c63c429, 0x42e6b214, 0x24855ea2, 0xfa00289f},
    {0x00000000, 0xd569796d, 0xaf3e842b, 0x7a57fd46, 0x5b917ea7, 0x8ef807ca,
     0xf4affa8c, 0x21c683e1, 0xb722fd4e, 0x624b8423, 0x181c7965, 0xcd750008,
     0xecb383e9, 0x39dafa84, 0x438d07c2, 0x96e47eaf},
    {0x00000000, 0x6ba98c6d, 0xd75318da, 0xbcfa94b7, 0xab4a4745, 0xc0e3cb28,
     0x7c195f9f, 0x17b0d3f2, 0x5378f87b, 0x38d17416, 0x842be0a1, 0xef826ccc,
     0xf832bf3e, 0x939b3353, 0x2f61a7e4, 0x44c82b89},
    {0x00000000, 0xa6f1f0f6, 0x480f971d, 0xeefe67eb, 0x901f2e3a, 0x36eedecc,
     0xd810b927, 0x7ee149d1, 0x25d22a85, 0x8323da73, 0x6dddbd98, 0xcb2c4d6e,
     0xb5cd04bf, 0x133cf449, 0xfdc293a2, 0x5b336354},
    {0x00000000, 0x4ba4550a, 0x9748aa14, 0xdcecff1e, 0x2b7d22d9, 0x60d977d3,
     0xbc3588cd, 0xf791ddc7, 0x56fa45b2, 0x1d5e10b8, 0xc1b2efa6, 0x8a16baac,
     0x7d87676b, 0x36233261, 0xeacfcd7f, 0xa16b9875},
    {0x00000000, 0xadf48b64, 0x5e056039, 0xf3f1eb5d, 0xbc0ac072, 0x11fe4b16,
     0xe20fa04b, 0x4ffb2b2f, 0x7df9f615, 0xd00d7d71, 0x23fc962c, 0x8e081d48,
     0xc1f33667, 0x6c07bd03, 0x9ff6565e, 0x3202dd3a},
};

constexpr const ptrdiff_t kPrefetchHorizon = 256;

}  // namespace

uint32_t ExtendSse42(uint32_t crc, const uint8_t* data, size_t size) {
  const uint8_t* p = data;
  const uint8_t* e = data + size;
  uint32_t l = crc ^ kCRC32Xor;

#define STEP1                  \
  do {                         \
    l = _mm_crc32_u8(l, *p++); \
  } while (0)

#define STEP4(crc)                             \
  do {                                         \
    crc = _mm_crc32_u32(crc, ReadUint32LE(p)); \
    p += 4;                                    \
  } while (0)

#define STEP8(crc, data)                          \
  do {                                            \
    crc = _mm_crc32_u64(crc, ReadUint64LE(data)); \
    data += 8;                                    \
  } while (0)

#define STEP8BY3(crc0, crc1, crc2, p0, p1, p2) \
  do {                                         \
    STEP8(crc0, p0);                           \
    STEP8(crc1, p1);                           \
    STEP8(crc2, p2);                           \
  } while (0)

#define STEP8X3(crc0, crc1, crc2, bs)                     \
  do {                                                    \
    crc0 = _mm_crc32_u64(crc0, ReadUint64LE(p));          \
    crc1 = _mm_crc32_u64(crc1, ReadUint64LE(p + bs));     \
    crc2 = _mm_crc32_u64(crc2, ReadUint64LE(p + 2 * bs)); \
    p += 8;                                               \
  } while (0)

#define SKIP_BLOCK(crc, tab)                                      \
  do {                                                            \
    crc = tab[0][crc & 0xf] ^ tab[1][(crc >> 4) & 0xf] ^          \
          tab[2][(crc >> 8) & 0xf] ^ tab[3][(crc >> 12) & 0xf] ^  \
          tab[4][(crc >> 16) & 0xf] ^ tab[5][(crc >> 20) & 0xf] ^ \
          tab[6][(crc >> 24) & 0xf] ^ tab[7][(crc >> 28) & 0xf];  \
  } while (0)

  // Point x at first 8-byte aligned byte in the buffer. This might be past the
  // end of the buffer.
  const uint8_t* x = RoundUp<8>(p);
  if (x <= e) {
    // Process bytes p is 8-byte aligned.
    while (p != x) {
      STEP1;
    }
  }

  // Proccess the data in predetermined block sizes with tables for quickly
  // combining the checksum. Experimentally it's better to use larger block
  // sizes where possible so use a hierarchy of decreasing block sizes.
  uint64_t l64 = l;
  while ((e - p) >= kGroups * kBlock0Size) {
    uint64_t l641 = 0;
    uint64_t l642 = 0;
    for (int i = 0; i < kBlock0Size; i += 8 * 8) {
      // Prefetch ahead to hide latency.
      RequestPrefetch(p + kPrefetchHorizon);
      RequestPrefetch(p + kBlock0Size + kPrefetchHorizon);
      RequestPrefetch(p + 2 * kBlock0Size + kPrefetchHorizon);

      // Process 64 bytes at a time.
      STEP8X3(l64, l641, l642, kBlock0Size);
      STEP8X3(l64, l641, l642, kBlock0Size);
      STEP8X3(l64, l641, l642, kBlock0Size);
      STEP8X3(l64, l641, l642, kBlock0Size);
      STEP8X3(l64, l641, l642, kBlock0Size);
      STEP8X3(l64, l641, l642, kBlock0Size);
      STEP8X3(l64, l641, l642, kBlock0Size);
      STEP8X3(l64, l641, l642, kBlock0Size);
    }

    // Combine results.
    SKIP_BLOCK(l64, kBlock0SkipTable);
    l64 ^= l641;
    SKIP_BLOCK(l64, kBlock0SkipTable);
    l64 ^= l642;
    p += (kGroups - 1) * kBlock0Size;
  }
  while ((e - p) >= kGroups * kBlock1Size) {
    uint64_t l641 = 0;
    uint64_t l642 = 0;
    for (int i = 0; i < kBlock1Size; i += 8) {
      STEP8X3(l64, l641, l642, kBlock1Size);
    }
    SKIP_BLOCK(l64, kBlock1SkipTable);
    l64 ^= l641;
    SKIP_BLOCK(l64, kBlock1SkipTable);
    l64 ^= l642;
    p += (kGroups - 1) * kBlock1Size;
  }
  while ((e - p) >= kGroups * kBlock2Size) {
    uint64_t l641 = 0;
    uint64_t l642 = 0;
    for (int i = 0; i < kBlock2Size; i += 8) {
      STEP8X3(l64, l641, l642, kBlock2Size);
    }
    SKIP_BLOCK(l64, kBlock2SkipTable);
    l64 ^= l641;
    SKIP_BLOCK(l64, kBlock2SkipTable);
    l64 ^= l642;
    p += (kGroups - 1) * kBlock2Size;
  }

  // Process bytes 16 at a time
  while ((e - p) >= 16) {
    STEP8(l64, p);
    STEP8(l64, p);
  }

  l = static_cast<uint32_t>(l64);
  // Process the last few bytes.
  while (p != e) {
    STEP1;
  }
#undef SKIP_BLOCK
#undef STEP8X3
#undef STEP8BY3
#undef STEP8
#undef STEP4
#undef STEP1

  return l ^ kCRC32Xor;
}

}  // namespace crc32c

#endif  // HAVE_SSE42 && (defined(_M_X64) || defined(__x86_64__))