/* * This file is part of the Aaru Data Preservation Suite. * Copyright (c) 2019-2023 Natalia Portillo. * Copyright 2017 The Chromium Authors. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following disclaimer * in the documentation and/or other materials provided with the * distribution. * * Neither the name of Google Inc. nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "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 * OWNER OR CONTRIBUTORS 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. */ #if defined(__x86_64__) || defined(__amd64) || defined(_M_AMD64) || defined(_M_X64) || defined(__I386__) || \ defined(__i386__) || defined(__THW_INTEL) || defined(_M_IX86) #include #include #include "library.h" #include "fletcher16.h" /** * @brief Calculate Fletcher-16 checksum for a given data using SSSE3 instructions. * * This function calculates the Fletcher-16 checksum for a block of data using SSSE3 vector instructions. * * @param sum1 Pointer to the variable where the first 8-bit checksum value is stored. * @param sum2 Pointer to the variable where the second 8-bit checksum value is stored. * @param data Pointer to the data buffer. * @param len Length of the data buffer in bytes. */ AARU_EXPORT TARGET_WITH_SSSE3 void AARU_CALL fletcher16_ssse3(uint8_t *sum1, uint8_t *sum2, const uint8_t *data, long len) { uint32_t s1 = *sum1; uint32_t s2 = *sum2; /* * Process the data in blocks. */ const unsigned BLOCK_SIZE = 1 << 5; if(len >= BLOCK_SIZE) { long blocks = len / BLOCK_SIZE; len -= blocks * BLOCK_SIZE; while(blocks) { unsigned n = NMAX / BLOCK_SIZE; /* The NMAX constraint. */ if(n > blocks) n = (unsigned)blocks; blocks -= n; const __m128i tap1 = _mm_setr_epi8(32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17); const __m128i tap2 = _mm_setr_epi8(16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1); const __m128i zero = _mm_setr_epi8(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0); const __m128i ones = _mm_set_epi16(1, 1, 1, 1, 1, 1, 1, 1); /* * Process n blocks of data. At most NMAX data bytes can be * processed before s2 must be reduced modulo BASE. */ __m128i v_ps = _mm_set_epi32(0, 0, 0, s1 * n); __m128i v_s2 = _mm_set_epi32(0, 0, 0, s2); __m128i v_s1 = _mm_set_epi32(0, 0, 0, 0); do { /* * Load 32 input bytes. */ const __m128i bytes1 = _mm_loadu_si128((__m128i *)(data)); const __m128i bytes2 = _mm_loadu_si128((__m128i *)(data + 16)); /* * Add previous block byte sum to v_ps. */ v_ps = _mm_add_epi32(v_ps, v_s1); /* * Horizontally add the bytes for s1, multiply-adds the * bytes by [ 32, 31, 30, ... ] for s2. */ v_s1 = _mm_add_epi32(v_s1, _mm_sad_epu8(bytes1, zero)); const __m128i mad1 = _mm_maddubs_epi16(bytes1, tap1); v_s2 = _mm_add_epi32(v_s2, _mm_madd_epi16(mad1, ones)); v_s1 = _mm_add_epi32(v_s1, _mm_sad_epu8(bytes2, zero)); const __m128i mad2 = _mm_maddubs_epi16(bytes2, tap2); v_s2 = _mm_add_epi32(v_s2, _mm_madd_epi16(mad2, ones)); data += BLOCK_SIZE; } while(--n); v_s2 = _mm_add_epi32(v_s2, _mm_slli_epi32(v_ps, 5)); /* * Sum epi32 ints v_s1(s2) and accumulate in s1(s2). */ #define S23O1 _MM_SHUFFLE(2, 3, 0, 1) /* A B C D -> B A D C */ #define S1O32 _MM_SHUFFLE(1, 0, 3, 2) /* A B C D -> C D A B */ v_s1 = _mm_add_epi32(v_s1, _mm_shuffle_epi32(v_s1, S23O1)); v_s1 = _mm_add_epi32(v_s1, _mm_shuffle_epi32(v_s1, S1O32)); s1 += _mm_cvtsi128_si32(v_s1); v_s2 = _mm_add_epi32(v_s2, _mm_shuffle_epi32(v_s2, S23O1)); v_s2 = _mm_add_epi32(v_s2, _mm_shuffle_epi32(v_s2, S1O32)); s2 = _mm_cvtsi128_si32(v_s2); #undef S23O1 #undef S1O32 /* * Reduce. */ s1 %= FLETCHER16_MODULE; s2 %= FLETCHER16_MODULE; } } /* * Handle leftover data. */ if(len) { if(len >= 16) { s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); s2 += (s1 += *data++); len -= 16; } while(len--) { s2 += (s1 += *data++); } s1 %= FLETCHER16_MODULE; s2 %= FLETCHER16_MODULE; } /* * Return the recombined sums. */ *sum1 = s1 & 0xFF; *sum2 = s2 & 0xFF; } #endif