f3eade2f62
Drop the AGPL license in favor of a source-available license. See the blog post [1] for details. [1] https://www.scylladb.com/2024/12/18/why-were-moving-to-a-source-available-license/
70 lines
1.5 KiB
C++
70 lines
1.5 KiB
C++
/*
|
|
* Copyright (C) 2018-present ScyllaDB
|
|
*/
|
|
|
|
/*
|
|
* SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
|
|
*
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <cstdint>
|
|
#include <type_traits>
|
|
|
|
inline
|
|
constexpr uint64_t clmul_u32_constexpr(uint32_t p1, uint32_t p2) {
|
|
uint64_t result = 0;
|
|
for (unsigned i = 0; i < 32; ++i) {
|
|
result ^= (((p1 >> i) & 1) * uint64_t(p2)) << i;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
// returns the low half of the result
|
|
inline
|
|
constexpr uint64_t clmul_u64_low_constexpr(uint64_t p1, uint64_t p2) {
|
|
uint64_t result = 0;
|
|
for (unsigned i = 0; i < 64; ++i) {
|
|
result ^= (((p1 >> i) & 1) * p2) << i;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
#if defined(__x86_64__) || defined(__i386__)
|
|
|
|
#include <wmmintrin.h>
|
|
#include <smmintrin.h>
|
|
|
|
// Performs a carry-less multiplication of two integers.
|
|
inline
|
|
uint64_t clmul_u32(uint32_t p1, uint32_t p2) {
|
|
__m128i p = _mm_set_epi64x(p1, p2);
|
|
p = _mm_clmulepi64_si128(p, p, 0x01);
|
|
return _mm_extract_epi64(p, 0);
|
|
}
|
|
|
|
constexpr
|
|
inline
|
|
uint64_t clmul(uint32_t p1, uint32_t p2) {
|
|
return std::is_constant_evaluated() ? clmul_u32_constexpr(p1, p2) : clmul_u32(p1, p2);
|
|
}
|
|
|
|
#elif defined(__aarch64__)
|
|
|
|
#include <arm_neon.h>
|
|
|
|
// Performs a carry-less multiplication of two integers.
|
|
inline
|
|
uint64_t clmul_u32(uint32_t p1, uint32_t p2) {
|
|
return vmull_p64(p1, p2);
|
|
}
|
|
|
|
constexpr
|
|
inline
|
|
uint64_t clmul(uint32_t p1, uint32_t p2) {
|
|
return std::is_constant_evaluated() ? clmul_u32_constexpr(p1, p2) : clmul_u32(p1, p2);
|
|
}
|
|
|
|
#endif
|