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-rw-r--r--mysys/crc32/crc32c_amd64.cc711
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diff --git a/mysys/crc32/crc32c_amd64.cc b/mysys/crc32/crc32c_amd64.cc
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+++ b/mysys/crc32/crc32c_amd64.cc
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+/* Copyright (c) 2020, 2021, MariaDB
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; version 2 of the License.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
+
+/*
+ * Copyright 2016 Ferry Toth, Exalon Delft BV, The Netherlands
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event will the author be held liable for any damages
+ * arising from the use of this software.
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ * 1. The origin of this software must not be misrepresented; you must not
+ * claim that you wrote the original software. If you use this software
+ * in a product, an acknowledgment in the product documentation would be
+ * appreciated but is not required.
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ * misrepresented as being the original software.
+ * 3. This notice may not be removed or altered from any source distribution.
+ * Ferry Toth
+ * ftoth@exalondelft.nl
+ *
+ * https://github.com/htot/crc32c
+ *
+ * Modified by Facebook
+ *
+ * Original intel whitepaper:
+ * "Fast CRC Computation for iSCSI Polynomial Using CRC32 Instruction"
+ * https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/crc-iscsi-polynomial-crc32-instruction-paper.pdf
+ *
+ * This version is from the folly library, created by Dave Watson <davejwatson@fb.com>
+ *
+*/
+
+#include <stdint.h>
+#include <nmmintrin.h>
+#include <wmmintrin.h>
+
+
+#define CRCtriplet(crc, buf, offset) \
+ crc##0 = _mm_crc32_u64(crc##0, *(buf##0 + offset)); \
+ crc##1 = _mm_crc32_u64(crc##1, *(buf##1 + offset)); \
+ crc##2 = _mm_crc32_u64(crc##2, *(buf##2 + offset));
+
+#define CRCduplet(crc, buf, offset) \
+ crc##0 = _mm_crc32_u64(crc##0, *(buf##0 + offset)); \
+ crc##1 = _mm_crc32_u64(crc##1, *(buf##1 + offset));
+
+#define CRCsinglet(crc, buf, offset) \
+ crc = _mm_crc32_u64(crc, *(uint64_t*)(buf + offset));
+
+
+// Numbers taken directly from intel whitepaper.
+// clang-format off
+static const uint64_t clmul_constants alignas(16) [] = {
+ 0x14cd00bd6, 0x105ec76f0, 0x0ba4fc28e, 0x14cd00bd6,
+ 0x1d82c63da, 0x0f20c0dfe, 0x09e4addf8, 0x0ba4fc28e,
+ 0x039d3b296, 0x1384aa63a, 0x102f9b8a2, 0x1d82c63da,
+ 0x14237f5e6, 0x01c291d04, 0x00d3b6092, 0x09e4addf8,
+ 0x0c96cfdc0, 0x0740eef02, 0x18266e456, 0x039d3b296,
+ 0x0daece73e, 0x0083a6eec, 0x0ab7aff2a, 0x102f9b8a2,
+ 0x1248ea574, 0x1c1733996, 0x083348832, 0x14237f5e6,
+ 0x12c743124, 0x02ad91c30, 0x0b9e02b86, 0x00d3b6092,
+ 0x018b33a4e, 0x06992cea2, 0x1b331e26a, 0x0c96cfdc0,
+ 0x17d35ba46, 0x07e908048, 0x1bf2e8b8a, 0x18266e456,
+ 0x1a3e0968a, 0x11ed1f9d8, 0x0ce7f39f4, 0x0daece73e,
+ 0x061d82e56, 0x0f1d0f55e, 0x0d270f1a2, 0x0ab7aff2a,
+ 0x1c3f5f66c, 0x0a87ab8a8, 0x12ed0daac, 0x1248ea574,
+ 0x065863b64, 0x08462d800, 0x11eef4f8e, 0x083348832,
+ 0x1ee54f54c, 0x071d111a8, 0x0b3e32c28, 0x12c743124,
+ 0x0064f7f26, 0x0ffd852c6, 0x0dd7e3b0c, 0x0b9e02b86,
+ 0x0f285651c, 0x0dcb17aa4, 0x010746f3c, 0x018b33a4e,
+ 0x1c24afea4, 0x0f37c5aee, 0x0271d9844, 0x1b331e26a,
+ 0x08e766a0c, 0x06051d5a2, 0x093a5f730, 0x17d35ba46,
+ 0x06cb08e5c, 0x11d5ca20e, 0x06b749fb2, 0x1bf2e8b8a,
+ 0x1167f94f2, 0x021f3d99c, 0x0cec3662e, 0x1a3e0968a,
+ 0x19329634a, 0x08f158014, 0x0e6fc4e6a, 0x0ce7f39f4,
+ 0x08227bb8a, 0x1a5e82106, 0x0b0cd4768, 0x061d82e56,
+ 0x13c2b89c4, 0x188815ab2, 0x0d7a4825c, 0x0d270f1a2,
+ 0x10f5ff2ba, 0x105405f3e, 0x00167d312, 0x1c3f5f66c,
+ 0x0f6076544, 0x0e9adf796, 0x026f6a60a, 0x12ed0daac,
+ 0x1a2adb74e, 0x096638b34, 0x19d34af3a, 0x065863b64,
+ 0x049c3cc9c, 0x1e50585a0, 0x068bce87a, 0x11eef4f8e,
+ 0x1524fa6c6, 0x19f1c69dc, 0x16cba8aca, 0x1ee54f54c,
+ 0x042d98888, 0x12913343e, 0x1329d9f7e, 0x0b3e32c28,
+ 0x1b1c69528, 0x088f25a3a, 0x02178513a, 0x0064f7f26,
+ 0x0e0ac139e, 0x04e36f0b0, 0x0170076fa, 0x0dd7e3b0c,
+ 0x141a1a2e2, 0x0bd6f81f8, 0x16ad828b4, 0x0f285651c,
+ 0x041d17b64, 0x19425cbba, 0x1fae1cc66, 0x010746f3c,
+ 0x1a75b4b00, 0x18db37e8a, 0x0f872e54c, 0x1c24afea4,
+ 0x01e41e9fc, 0x04c144932, 0x086d8e4d2, 0x0271d9844,
+ 0x160f7af7a, 0x052148f02, 0x05bb8f1bc, 0x08e766a0c,
+ 0x0a90fd27a, 0x0a3c6f37a, 0x0b3af077a, 0x093a5f730,
+ 0x04984d782, 0x1d22c238e, 0x0ca6ef3ac, 0x06cb08e5c,
+ 0x0234e0b26, 0x063ded06a, 0x1d88abd4a, 0x06b749fb2,
+ 0x04597456a, 0x04d56973c, 0x0e9e28eb4, 0x1167f94f2,
+ 0x07b3ff57a, 0x19385bf2e, 0x0c9c8b782, 0x0cec3662e,
+ 0x13a9cba9e, 0x0e417f38a, 0x093e106a4, 0x19329634a,
+ 0x167001a9c, 0x14e727980, 0x1ddffc5d4, 0x0e6fc4e6a,
+ 0x00df04680, 0x0d104b8fc, 0x02342001e, 0x08227bb8a,
+ 0x00a2a8d7e, 0x05b397730, 0x168763fa6, 0x0b0cd4768,
+ 0x1ed5a407a, 0x0e78eb416, 0x0d2c3ed1a, 0x13c2b89c4,
+ 0x0995a5724, 0x1641378f0, 0x19b1afbc4, 0x0d7a4825c,
+ 0x109ffedc0, 0x08d96551c, 0x0f2271e60, 0x10f5ff2ba,
+ 0x00b0bf8ca, 0x00bf80dd2, 0x123888b7a, 0x00167d312,
+ 0x1e888f7dc, 0x18dcddd1c, 0x002ee03b2, 0x0f6076544,
+ 0x183e8d8fe, 0x06a45d2b2, 0x133d7a042, 0x026f6a60a,
+ 0x116b0f50c, 0x1dd3e10e8, 0x05fabe670, 0x1a2adb74e,
+ 0x130004488, 0x0de87806c, 0x000bcf5f6, 0x19d34af3a,
+ 0x18f0c7078, 0x014338754, 0x017f27698, 0x049c3cc9c,
+ 0x058ca5f00, 0x15e3e77ee, 0x1af900c24, 0x068bce87a,
+ 0x0b5cfca28, 0x0dd07448e, 0x0ded288f8, 0x1524fa6c6,
+ 0x059f229bc, 0x1d8048348, 0x06d390dec, 0x16cba8aca,
+ 0x037170390, 0x0a3e3e02c, 0x06353c1cc, 0x042d98888,
+ 0x0c4584f5c, 0x0d73c7bea, 0x1f16a3418, 0x1329d9f7e,
+ 0x0531377e2, 0x185137662, 0x1d8d9ca7c, 0x1b1c69528,
+ 0x0b25b29f2, 0x18a08b5bc, 0x19fb2a8b0, 0x02178513a,
+ 0x1a08fe6ac, 0x1da758ae0, 0x045cddf4e, 0x0e0ac139e,
+ 0x1a91647f2, 0x169cf9eb0, 0x1a0f717c4, 0x0170076fa,
+};
+
+// Compute the crc32c value for buffer smaller than 8
+static inline void align_to_8(
+ size_t len,
+ uint64_t& crc0, // crc so far, updated on return
+ const unsigned char*& next) { // next data pointer, updated on return
+ uint32_t crc32bit = static_cast<uint32_t>(crc0);
+ if (len & 0x04) {
+ crc32bit = _mm_crc32_u32(crc32bit, *(uint32_t*)next);
+ next += sizeof(uint32_t);
+ }
+ if (len & 0x02) {
+ crc32bit = _mm_crc32_u16(crc32bit, *(uint16_t*)next);
+ next += sizeof(uint16_t);
+ }
+ if (len & 0x01) {
+ crc32bit = _mm_crc32_u8(crc32bit, *(next));
+ next++;
+ }
+ crc0 = crc32bit;
+}
+
+//
+// CombineCRC performs pclmulqdq multiplication of 2 partial CRC's and a well
+// chosen constant and xor's these with the remaining CRC.
+//
+static inline uint64_t CombineCRC(
+ size_t block_size,
+ uint64_t crc0,
+ uint64_t crc1,
+ uint64_t crc2,
+ const uint64_t* next2) {
+ const auto multiplier =
+ *(reinterpret_cast<const __m128i*>(clmul_constants) + block_size - 1);
+ const auto crc0_xmm = _mm_set_epi64x(0, crc0);
+ const auto res0 = _mm_clmulepi64_si128(crc0_xmm, multiplier, 0x00);
+ const auto crc1_xmm = _mm_set_epi64x(0, crc1);
+ const auto res1 = _mm_clmulepi64_si128(crc1_xmm, multiplier, 0x10);
+ const auto res = _mm_xor_si128(res0, res1);
+ crc0 = _mm_cvtsi128_si64(res);
+ crc0 = crc0 ^ *((uint64_t*)next2 - 1);
+ crc2 = _mm_crc32_u64(crc2, crc0);
+ return crc2;
+}
+
+// Compute CRC-32C using the Intel hardware instruction.
+extern "C"
+uint32_t crc32c_3way(uint32_t crc, const char *buf, size_t len)
+{
+ const unsigned char* next = (const unsigned char*)buf;
+ uint64_t count;
+ uint64_t crc0, crc1, crc2;
+ crc0 = crc ^ 0xffffffffu;
+
+
+ if (len >= 8) {
+ // if len > 216 then align and use triplets
+ if (len > 216) {
+ {
+ // Work on the bytes (< 8) before the first 8-byte alignment addr starts
+ auto align_bytes = (8 - (uintptr_t)next) & 7;
+ len -= align_bytes;
+ align_to_8(align_bytes, crc0, next);
+ }
+
+ // Now work on the remaining blocks
+ count = len / 24; // number of triplets
+ len %= 24; // bytes remaining
+ uint64_t n = count >> 7; // #blocks = first block + full blocks
+ uint64_t block_size = count & 127;
+ if (block_size == 0) {
+ block_size = 128;
+ } else {
+ n++;
+ }
+ // points to the first byte of the next block
+ const uint64_t* next0 = (uint64_t*)next + block_size;
+ const uint64_t* next1 = next0 + block_size;
+ const uint64_t* next2 = next1 + block_size;
+
+ crc1 = crc2 = 0;
+ // Use Duff's device, a for() loop inside a switch()
+ // statement. This needs to execute at least once, round len
+ // down to nearest triplet multiple
+ switch (block_size) {
+ case 128:
+ do {
+ // jumps here for a full block of len 128
+ CRCtriplet(crc, next, -128);
+ /* fallthrough */
+ case 127:
+ // jumps here or below for the first block smaller
+ CRCtriplet(crc, next, -127);
+ /* fallthrough */
+ case 126:
+ CRCtriplet(crc, next, -126); // than 128
+ /* fallthrough */
+ case 125:
+ CRCtriplet(crc, next, -125);
+ /* fallthrough */
+ case 124:
+ CRCtriplet(crc, next, -124);
+ /* fallthrough */
+ case 123:
+ CRCtriplet(crc, next, -123);
+ /* fallthrough */
+ case 122:
+ CRCtriplet(crc, next, -122);
+ /* fallthrough */
+ case 121:
+ CRCtriplet(crc, next, -121);
+ /* fallthrough */
+ case 120:
+ CRCtriplet(crc, next, -120);
+ /* fallthrough */
+ case 119:
+ CRCtriplet(crc, next, -119);
+ /* fallthrough */
+ case 118:
+ CRCtriplet(crc, next, -118);
+ /* fallthrough */
+ case 117:
+ CRCtriplet(crc, next, -117);
+ /* fallthrough */
+ case 116:
+ CRCtriplet(crc, next, -116);
+ /* fallthrough */
+ case 115:
+ CRCtriplet(crc, next, -115);
+ /* fallthrough */
+ case 114:
+ CRCtriplet(crc, next, -114);
+ /* fallthrough */
+ case 113:
+ CRCtriplet(crc, next, -113);
+ /* fallthrough */
+ case 112:
+ CRCtriplet(crc, next, -112);
+ /* fallthrough */
+ case 111:
+ CRCtriplet(crc, next, -111);
+ /* fallthrough */
+ case 110:
+ CRCtriplet(crc, next, -110);
+ /* fallthrough */
+ case 109:
+ CRCtriplet(crc, next, -109);
+ /* fallthrough */
+ case 108:
+ CRCtriplet(crc, next, -108);
+ /* fallthrough */
+ case 107:
+ CRCtriplet(crc, next, -107);
+ /* fallthrough */
+ case 106:
+ CRCtriplet(crc, next, -106);
+ /* fallthrough */
+ case 105:
+ CRCtriplet(crc, next, -105);
+ /* fallthrough */
+ case 104:
+ CRCtriplet(crc, next, -104);
+ /* fallthrough */
+ case 103:
+ CRCtriplet(crc, next, -103);
+ /* fallthrough */
+ case 102:
+ CRCtriplet(crc, next, -102);
+ /* fallthrough */
+ case 101:
+ CRCtriplet(crc, next, -101);
+ /* fallthrough */
+ case 100:
+ CRCtriplet(crc, next, -100);
+ /* fallthrough */
+ case 99:
+ CRCtriplet(crc, next, -99);
+ /* fallthrough */
+ case 98:
+ CRCtriplet(crc, next, -98);
+ /* fallthrough */
+ case 97:
+ CRCtriplet(crc, next, -97);
+ /* fallthrough */
+ case 96:
+ CRCtriplet(crc, next, -96);
+ /* fallthrough */
+ case 95:
+ CRCtriplet(crc, next, -95);
+ /* fallthrough */
+ case 94:
+ CRCtriplet(crc, next, -94);
+ /* fallthrough */
+ case 93:
+ CRCtriplet(crc, next, -93);
+ /* fallthrough */
+ case 92:
+ CRCtriplet(crc, next, -92);
+ /* fallthrough */
+ case 91:
+ CRCtriplet(crc, next, -91);
+ /* fallthrough */
+ case 90:
+ CRCtriplet(crc, next, -90);
+ /* fallthrough */
+ case 89:
+ CRCtriplet(crc, next, -89);
+ /* fallthrough */
+ case 88:
+ CRCtriplet(crc, next, -88);
+ /* fallthrough */
+ case 87:
+ CRCtriplet(crc, next, -87);
+ /* fallthrough */
+ case 86:
+ CRCtriplet(crc, next, -86);
+ /* fallthrough */
+ case 85:
+ CRCtriplet(crc, next, -85);
+ /* fallthrough */
+ case 84:
+ CRCtriplet(crc, next, -84);
+ /* fallthrough */
+ case 83:
+ CRCtriplet(crc, next, -83);
+ /* fallthrough */
+ case 82:
+ CRCtriplet(crc, next, -82);
+ /* fallthrough */
+ case 81:
+ CRCtriplet(crc, next, -81);
+ /* fallthrough */
+ case 80:
+ CRCtriplet(crc, next, -80);
+ /* fallthrough */
+ case 79:
+ CRCtriplet(crc, next, -79);
+ /* fallthrough */
+ case 78:
+ CRCtriplet(crc, next, -78);
+ /* fallthrough */
+ case 77:
+ CRCtriplet(crc, next, -77);
+ /* fallthrough */
+ case 76:
+ CRCtriplet(crc, next, -76);
+ /* fallthrough */
+ case 75:
+ CRCtriplet(crc, next, -75);
+ /* fallthrough */
+ case 74:
+ CRCtriplet(crc, next, -74);
+ /* fallthrough */
+ case 73:
+ CRCtriplet(crc, next, -73);
+ /* fallthrough */
+ case 72:
+ CRCtriplet(crc, next, -72);
+ /* fallthrough */
+ case 71:
+ CRCtriplet(crc, next, -71);
+ /* fallthrough */
+ case 70:
+ CRCtriplet(crc, next, -70);
+ /* fallthrough */
+ case 69:
+ CRCtriplet(crc, next, -69);
+ /* fallthrough */
+ case 68:
+ CRCtriplet(crc, next, -68);
+ /* fallthrough */
+ case 67:
+ CRCtriplet(crc, next, -67);
+ /* fallthrough */
+ case 66:
+ CRCtriplet(crc, next, -66);
+ /* fallthrough */
+ case 65:
+ CRCtriplet(crc, next, -65);
+ /* fallthrough */
+ case 64:
+ CRCtriplet(crc, next, -64);
+ /* fallthrough */
+ case 63:
+ CRCtriplet(crc, next, -63);
+ /* fallthrough */
+ case 62:
+ CRCtriplet(crc, next, -62);
+ /* fallthrough */
+ case 61:
+ CRCtriplet(crc, next, -61);
+ /* fallthrough */
+ case 60:
+ CRCtriplet(crc, next, -60);
+ /* fallthrough */
+ case 59:
+ CRCtriplet(crc, next, -59);
+ /* fallthrough */
+ case 58:
+ CRCtriplet(crc, next, -58);
+ /* fallthrough */
+ case 57:
+ CRCtriplet(crc, next, -57);
+ /* fallthrough */
+ case 56:
+ CRCtriplet(crc, next, -56);
+ /* fallthrough */
+ case 55:
+ CRCtriplet(crc, next, -55);
+ /* fallthrough */
+ case 54:
+ CRCtriplet(crc, next, -54);
+ /* fallthrough */
+ case 53:
+ CRCtriplet(crc, next, -53);
+ /* fallthrough */
+ case 52:
+ CRCtriplet(crc, next, -52);
+ /* fallthrough */
+ case 51:
+ CRCtriplet(crc, next, -51);
+ /* fallthrough */
+ case 50:
+ CRCtriplet(crc, next, -50);
+ /* fallthrough */
+ case 49:
+ CRCtriplet(crc, next, -49);
+ /* fallthrough */
+ case 48:
+ CRCtriplet(crc, next, -48);
+ /* fallthrough */
+ case 47:
+ CRCtriplet(crc, next, -47);
+ /* fallthrough */
+ case 46:
+ CRCtriplet(crc, next, -46);
+ /* fallthrough */
+ case 45:
+ CRCtriplet(crc, next, -45);
+ /* fallthrough */
+ case 44:
+ CRCtriplet(crc, next, -44);
+ /* fallthrough */
+ case 43:
+ CRCtriplet(crc, next, -43);
+ /* fallthrough */
+ case 42:
+ CRCtriplet(crc, next, -42);
+ /* fallthrough */
+ case 41:
+ CRCtriplet(crc, next, -41);
+ /* fallthrough */
+ case 40:
+ CRCtriplet(crc, next, -40);
+ /* fallthrough */
+ case 39:
+ CRCtriplet(crc, next, -39);
+ /* fallthrough */
+ case 38:
+ CRCtriplet(crc, next, -38);
+ /* fallthrough */
+ case 37:
+ CRCtriplet(crc, next, -37);
+ /* fallthrough */
+ case 36:
+ CRCtriplet(crc, next, -36);
+ /* fallthrough */
+ case 35:
+ CRCtriplet(crc, next, -35);
+ /* fallthrough */
+ case 34:
+ CRCtriplet(crc, next, -34);
+ /* fallthrough */
+ case 33:
+ CRCtriplet(crc, next, -33);
+ /* fallthrough */
+ case 32:
+ CRCtriplet(crc, next, -32);
+ /* fallthrough */
+ case 31:
+ CRCtriplet(crc, next, -31);
+ /* fallthrough */
+ case 30:
+ CRCtriplet(crc, next, -30);
+ /* fallthrough */
+ case 29:
+ CRCtriplet(crc, next, -29);
+ /* fallthrough */
+ case 28:
+ CRCtriplet(crc, next, -28);
+ /* fallthrough */
+ case 27:
+ CRCtriplet(crc, next, -27);
+ /* fallthrough */
+ case 26:
+ CRCtriplet(crc, next, -26);
+ /* fallthrough */
+ case 25:
+ CRCtriplet(crc, next, -25);
+ /* fallthrough */
+ case 24:
+ CRCtriplet(crc, next, -24);
+ /* fallthrough */
+ case 23:
+ CRCtriplet(crc, next, -23);
+ /* fallthrough */
+ case 22:
+ CRCtriplet(crc, next, -22);
+ /* fallthrough */
+ case 21:
+ CRCtriplet(crc, next, -21);
+ /* fallthrough */
+ case 20:
+ CRCtriplet(crc, next, -20);
+ /* fallthrough */
+ case 19:
+ CRCtriplet(crc, next, -19);
+ /* fallthrough */
+ case 18:
+ CRCtriplet(crc, next, -18);
+ /* fallthrough */
+ case 17:
+ CRCtriplet(crc, next, -17);
+ /* fallthrough */
+ case 16:
+ CRCtriplet(crc, next, -16);
+ /* fallthrough */
+ case 15:
+ CRCtriplet(crc, next, -15);
+ /* fallthrough */
+ case 14:
+ CRCtriplet(crc, next, -14);
+ /* fallthrough */
+ case 13:
+ CRCtriplet(crc, next, -13);
+ /* fallthrough */
+ case 12:
+ CRCtriplet(crc, next, -12);
+ /* fallthrough */
+ case 11:
+ CRCtriplet(crc, next, -11);
+ /* fallthrough */
+ case 10:
+ CRCtriplet(crc, next, -10);
+ /* fallthrough */
+ case 9:
+ CRCtriplet(crc, next, -9);
+ /* fallthrough */
+ case 8:
+ CRCtriplet(crc, next, -8);
+ /* fallthrough */
+ case 7:
+ CRCtriplet(crc, next, -7);
+ /* fallthrough */
+ case 6:
+ CRCtriplet(crc, next, -6);
+ /* fallthrough */
+ case 5:
+ CRCtriplet(crc, next, -5);
+ /* fallthrough */
+ case 4:
+ CRCtriplet(crc, next, -4);
+ /* fallthrough */
+ case 3:
+ CRCtriplet(crc, next, -3);
+ /* fallthrough */
+ case 2:
+ CRCtriplet(crc, next, -2);
+ /* fallthrough */
+ case 1:
+ CRCduplet(crc, next, -1); // the final triplet is actually only 2
+ //{ CombineCRC(); }
+ crc0 = CombineCRC(block_size, crc0, crc1, crc2, next2);
+ if (--n > 0) {
+ crc1 = crc2 = 0;
+ block_size = 128;
+ // points to the first byte of the next block
+ next0 = next2 + 128;
+ next1 = next0 + 128; // from here on all blocks are 128 long
+ next2 = next1 + 128;
+ }
+ /* fallthrough */
+ case 0:;
+ } while (n > 0);
+ }
+ next = (const unsigned char*)next2;
+ }
+ uint64_t count2 = len >> 3; // 216 of less bytes is 27 or less singlets
+ len = len & 7;
+ next += (count2 * 8);
+ switch (count2) {
+ case 27:
+ CRCsinglet(crc0, next, -27 * 8);
+ /* fallthrough */
+ case 26:
+ CRCsinglet(crc0, next, -26 * 8);
+ /* fallthrough */
+ case 25:
+ CRCsinglet(crc0, next, -25 * 8);
+ /* fallthrough */
+ case 24:
+ CRCsinglet(crc0, next, -24 * 8);
+ /* fallthrough */
+ case 23:
+ CRCsinglet(crc0, next, -23 * 8);
+ /* fallthrough */
+ case 22:
+ CRCsinglet(crc0, next, -22 * 8);
+ /* fallthrough */
+ case 21:
+ CRCsinglet(crc0, next, -21 * 8);
+ /* fallthrough */
+ case 20:
+ CRCsinglet(crc0, next, -20 * 8);
+ /* fallthrough */
+ case 19:
+ CRCsinglet(crc0, next, -19 * 8);
+ /* fallthrough */
+ case 18:
+ CRCsinglet(crc0, next, -18 * 8);
+ /* fallthrough */
+ case 17:
+ CRCsinglet(crc0, next, -17 * 8);
+ /* fallthrough */
+ case 16:
+ CRCsinglet(crc0, next, -16 * 8);
+ /* fallthrough */
+ case 15:
+ CRCsinglet(crc0, next, -15 * 8);
+ /* fallthrough */
+ case 14:
+ CRCsinglet(crc0, next, -14 * 8);
+ /* fallthrough */
+ case 13:
+ CRCsinglet(crc0, next, -13 * 8);
+ /* fallthrough */
+ case 12:
+ CRCsinglet(crc0, next, -12 * 8);
+ /* fallthrough */
+ case 11:
+ CRCsinglet(crc0, next, -11 * 8);
+ /* fallthrough */
+ case 10:
+ CRCsinglet(crc0, next, -10 * 8);
+ /* fallthrough */
+ case 9:
+ CRCsinglet(crc0, next, -9 * 8);
+ /* fallthrough */
+ case 8:
+ CRCsinglet(crc0, next, -8 * 8);
+ /* fallthrough */
+ case 7:
+ CRCsinglet(crc0, next, -7 * 8);
+ /* fallthrough */
+ case 6:
+ CRCsinglet(crc0, next, -6 * 8);
+ /* fallthrough */
+ case 5:
+ CRCsinglet(crc0, next, -5 * 8);
+ /* fallthrough */
+ case 4:
+ CRCsinglet(crc0, next, -4 * 8);
+ /* fallthrough */
+ case 3:
+ CRCsinglet(crc0, next, -3 * 8);
+ /* fallthrough */
+ case 2:
+ CRCsinglet(crc0, next, -2 * 8);
+ /* fallthrough */
+ case 1:
+ CRCsinglet(crc0, next, -1 * 8);
+ /* fallthrough */
+ case 0:;
+ }
+ }
+ {
+ align_to_8(len, crc0, next);
+ return (uint32_t)crc0 ^ 0xffffffffu;
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-20 07:54:19 +0000