mirror of
https://github.com/henrydcase/pqc.git
synced 2024-11-24 00:11:27 +00:00
70 lines
2.6 KiB
C
70 lines
2.6 KiB
C
#include "cbd.h"
|
|
#include "params.h"
|
|
|
|
#include <immintrin.h>
|
|
#include <stdint.h>
|
|
|
|
/*************************************************
|
|
* Name: cbd
|
|
*
|
|
* Description: Given an array of uniformly random bytes, compute
|
|
* polynomial with coefficients distributed according to
|
|
* a centered binomial distribution with parameter KYBER_ETA
|
|
*
|
|
* Arguments: - poly *r: pointer to output polynomial
|
|
* - const uint8_t *buf: pointer to input byte array
|
|
**************************************************/
|
|
void PQCLEAN_KYBER102490S_AVX2_cbd(poly *r, const uint8_t *buf) {
|
|
__m256i vec0, vec1, vec2, vec3, tmp;
|
|
const __m256i mask55 = _mm256_set1_epi32(0x55555555);
|
|
const __m256i mask33 = _mm256_set1_epi32(0x33333333);
|
|
const __m256i mask03 = _mm256_set1_epi32(0x03030303);
|
|
|
|
for (size_t i = 0; i < KYBER_N / 64; i++) {
|
|
vec0 = _mm256_loadu_si256((__m256i *)&buf[32 * i]);
|
|
|
|
vec1 = _mm256_srli_epi32(vec0, 1);
|
|
vec0 = _mm256_and_si256(mask55, vec0);
|
|
vec1 = _mm256_and_si256(mask55, vec1);
|
|
vec0 = _mm256_add_epi32(vec0, vec1);
|
|
|
|
vec1 = _mm256_srli_epi32(vec0, 2);
|
|
vec0 = _mm256_and_si256(mask33, vec0);
|
|
vec1 = _mm256_and_si256(mask33, vec1);
|
|
|
|
vec2 = _mm256_srli_epi32(vec0, 4);
|
|
vec3 = _mm256_srli_epi32(vec1, 4);
|
|
vec0 = _mm256_and_si256(mask03, vec0);
|
|
vec1 = _mm256_and_si256(mask03, vec1);
|
|
vec2 = _mm256_and_si256(mask03, vec2);
|
|
vec3 = _mm256_and_si256(mask03, vec3);
|
|
|
|
vec1 = _mm256_sub_epi8(vec0, vec1);
|
|
vec3 = _mm256_sub_epi8(vec2, vec3);
|
|
|
|
vec0 = _mm256_cvtepi8_epi16(_mm256_castsi256_si128(vec1));
|
|
vec1 = _mm256_cvtepi8_epi16(_mm256_extracti128_si256(vec1, 1));
|
|
vec2 = _mm256_cvtepi8_epi16(_mm256_castsi256_si128(vec3));
|
|
vec3 = _mm256_cvtepi8_epi16(_mm256_extracti128_si256(vec3, 1));
|
|
|
|
tmp = _mm256_unpacklo_epi16(vec0, vec2);
|
|
vec2 = _mm256_unpackhi_epi16(vec0, vec2);
|
|
vec0 = tmp;
|
|
tmp = _mm256_unpacklo_epi16(vec1, vec3);
|
|
vec3 = _mm256_unpackhi_epi16(vec1, vec3);
|
|
vec1 = tmp;
|
|
|
|
tmp = _mm256_permute2x128_si256(vec0, vec2, 0x20);
|
|
vec2 = _mm256_permute2x128_si256(vec0, vec2, 0x31);
|
|
vec0 = tmp;
|
|
tmp = _mm256_permute2x128_si256(vec1, vec3, 0x20);
|
|
vec3 = _mm256_permute2x128_si256(vec1, vec3, 0x31);
|
|
vec1 = tmp;
|
|
|
|
_mm256_store_si256((__m256i *)&r->coeffs[64 * i + 0], vec0);
|
|
_mm256_store_si256((__m256i *)&r->coeffs[64 * i + 16], vec2);
|
|
_mm256_store_si256((__m256i *)&r->coeffs[64 * i + 32], vec1);
|
|
_mm256_store_si256((__m256i *)&r->coeffs[64 * i + 48], vec3);
|
|
}
|
|
}
|