#include "align.h" #include "consts.h" #include "params.h" #include "rejsample.h" #include <immintrin.h> #include <stdint.h> #include <string.h> //#define BMI #define _mm256_cmpge_epu16(a, b) _mm256_cmpeq_epi16(_mm256_max_epu16(a, b), a) #define _mm_cmpge_epu16(a, b) _mm_cmpeq_epi16(_mm_max_epu16(a, b), a) unsigned int PQCLEAN_KYBER768_AVX2_rej_uniform_avx(int16_t *restrict r, const uint8_t *buf) { unsigned int ctr, pos; uint16_t val0, val1; uint32_t good; uint64_t idx0, idx1, idx2, idx3; const __m256i bound = _mm256_load_si256(&PQCLEAN_KYBER768_AVX2_qdata.vec[_16XQ / 16]); const __m256i ones = _mm256_set1_epi8(1); const __m256i mask = _mm256_set1_epi16(0xFFF); const __m256i idx8 = _mm256_set_epi8(15, 14, 14, 13, 12, 11, 11, 10, 9, 8, 8, 7, 6, 5, 5, 4, 11, 10, 10, 9, 8, 7, 7, 6, 5, 4, 4, 3, 2, 1, 1, 0); __m256i f0, f1, g0, g1, g2, g3; __m128i f, t, pilo, pihi; ctr = pos = 0; while (ctr <= KYBER_N - 32 && pos <= REJ_UNIFORM_AVX_BUFLEN - 48) { f0 = _mm256_loadu_si256((__m256i *)&buf[pos]); f1 = _mm256_loadu_si256((__m256i *)&buf[pos + 24]); f0 = _mm256_permute4x64_epi64(f0, 0x94); f1 = _mm256_permute4x64_epi64(f1, 0x94); f0 = _mm256_shuffle_epi8(f0, idx8); f1 = _mm256_shuffle_epi8(f1, idx8); g0 = _mm256_srli_epi16(f0, 4); g1 = _mm256_srli_epi16(f1, 4); f0 = _mm256_blend_epi16(f0, g0, 0xAA); f1 = _mm256_blend_epi16(f1, g1, 0xAA); f0 = _mm256_and_si256(f0, mask); f1 = _mm256_and_si256(f1, mask); pos += 48; g0 = _mm256_cmpgt_epi16(bound, f0); g1 = _mm256_cmpgt_epi16(bound, f1); g0 = _mm256_packs_epi16(g0, g1); good = _mm256_movemask_epi8(g0); idx0 = _pdep_u64(good >> 0, 0x0101010101010101); idx1 = _pdep_u64(good >> 8, 0x0101010101010101); idx2 = _pdep_u64(good >> 16, 0x0101010101010101); idx3 = _pdep_u64(good >> 24, 0x0101010101010101); idx0 = (idx0 << 8) - idx0; idx0 = _pext_u64(0x0E0C0A0806040200, idx0); idx1 = (idx1 << 8) - idx1; idx1 = _pext_u64(0x0E0C0A0806040200, idx1); idx2 = (idx2 << 8) - idx2; idx2 = _pext_u64(0x0E0C0A0806040200, idx2); idx3 = (idx3 << 8) - idx3; idx3 = _pext_u64(0x0E0C0A0806040200, idx3); g0 = _mm256_castsi128_si256(_mm_cvtsi64_si128(idx0)); g1 = _mm256_castsi128_si256(_mm_cvtsi64_si128(idx1)); g0 = _mm256_inserti128_si256(g0, _mm_cvtsi64_si128(idx2), 1); g1 = _mm256_inserti128_si256(g1, _mm_cvtsi64_si128(idx3), 1); g2 = _mm256_add_epi8(g0, ones); g3 = _mm256_add_epi8(g1, ones); g0 = _mm256_unpacklo_epi8(g0, g2); g1 = _mm256_unpacklo_epi8(g1, g3); f0 = _mm256_shuffle_epi8(f0, g0); f1 = _mm256_shuffle_epi8(f1, g1); _mm_storeu_si128((__m128i *)&r[ctr], _mm256_castsi256_si128(f0)); ctr += _mm_popcnt_u32((good >> 0) & 0xFF); _mm_storeu_si128((__m128i *)&r[ctr], _mm256_extracti128_si256(f0, 1)); ctr += _mm_popcnt_u32((good >> 16) & 0xFF); _mm_storeu_si128((__m128i *)&r[ctr], _mm256_castsi256_si128(f1)); ctr += _mm_popcnt_u32((good >> 8) & 0xFF); _mm_storeu_si128((__m128i *)&r[ctr], _mm256_extracti128_si256(f1, 1)); ctr += _mm_popcnt_u32((good >> 24) & 0xFF); } while (ctr <= KYBER_N - 8 && pos <= REJ_UNIFORM_AVX_BUFLEN - 12) { f = _mm_loadu_si128((__m128i *)&buf[pos]); f = _mm_shuffle_epi8(f, _mm256_castsi256_si128(idx8)); t = _mm_srli_epi16(f, 4); f = _mm_blend_epi16(f, t, 0xAA); f = _mm_and_si128(f, _mm256_castsi256_si128(mask)); pos += 12; t = _mm_cmpgt_epi16(_mm256_castsi256_si128(bound), f); good = _mm_movemask_epi8(t); good &= 0x5555; idx0 = _pdep_u64(good, 0x1111111111111111); idx0 = (idx0 << 8) - idx0; idx0 = _pext_u64(0x0E0C0A0806040200, idx0); pilo = _mm_cvtsi64_si128(idx0); pihi = _mm_add_epi8(pilo, _mm256_castsi256_si128(ones)); pilo = _mm_unpacklo_epi8(pilo, pihi); f = _mm_shuffle_epi8(f, pilo); _mm_storeu_si128((__m128i *)&r[ctr], f); ctr += _mm_popcnt_u32(good); } while (ctr < KYBER_N && pos <= REJ_UNIFORM_AVX_BUFLEN - 3) { val0 = ((buf[pos + 0] >> 0) | ((uint16_t)buf[pos + 1] << 8)) & 0xFFF; val1 = ((buf[pos + 1] >> 4) | ((uint16_t)buf[pos + 2] << 4)); pos += 3; if (val0 < KYBER_Q) { r[ctr++] = val0; } if (val1 < KYBER_Q && ctr < KYBER_N) { r[ctr++] = val1; } } return ctr; }