113 lines
3.8 KiB
C++
113 lines
3.8 KiB
C++
/*
|
|
* Copyright (c) Facebook, Inc. and its affiliates.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <folly/Portability.h>
|
|
|
|
#if FOLLY_SSE_PREREQ(4, 2)
|
|
#include <immintrin.h>
|
|
#endif
|
|
|
|
#include <stdint.h>
|
|
#include <cstddef>
|
|
|
|
namespace folly {
|
|
namespace detail {
|
|
|
|
/**
|
|
* Compute a CRC-32C checksum of a buffer using a hardware-accelerated
|
|
* implementation.
|
|
*
|
|
* @note This function is exposed to support special cases where the
|
|
* calling code is absolutely certain it ought to invoke a hardware-
|
|
* accelerated CRC-32C implementation - unit tests, for example. For
|
|
* all other scenarios, please call crc32c() and let it pick an
|
|
* implementation based on the capabilities of the underlying CPU.
|
|
*/
|
|
uint32_t
|
|
crc32c_hw(const uint8_t* data, size_t nbytes, uint32_t startingChecksum = ~0U);
|
|
|
|
/**
|
|
* Check whether a hardware-accelerated CRC-32C implementation is
|
|
* supported on the current CPU.
|
|
*/
|
|
bool crc32c_hw_supported();
|
|
|
|
/**
|
|
* Compute a CRC-32C checksum of a buffer using a portable,
|
|
* software-only implementation.
|
|
*
|
|
* @note This function is exposed to support special cases where the
|
|
* calling code is absolutely certain it wants to use the software
|
|
* implementation instead of the hardware-accelerated code - unit
|
|
* tests, for example. For all other scenarios, please call crc32c()
|
|
* and let it pick an implementation based on the capabilities of
|
|
* the underlying CPU.
|
|
*/
|
|
uint32_t
|
|
crc32c_sw(const uint8_t* data, size_t nbytes, uint32_t startingChecksum = ~0U);
|
|
|
|
/**
|
|
* Compute a CRC-32 checksum of a buffer using a hardware-accelerated
|
|
* implementation.
|
|
*
|
|
* @note This function is exposed to support special cases where the
|
|
* calling code is absolutely certain it ought to invoke a hardware-
|
|
* accelerated CRC-32 implementation - unit tests, for example. For
|
|
* all other scenarios, please call crc32() and let it pick an
|
|
* implementation based on the capabilities of the underlying CPU.
|
|
*/
|
|
uint32_t
|
|
crc32_hw(const uint8_t* data, size_t nbytes, uint32_t startingChecksum = ~0U);
|
|
|
|
#if FOLLY_SSE_PREREQ(4, 2)
|
|
uint32_t
|
|
crc32_hw_aligned(uint32_t remainder, const __m128i* p, size_t vec_count);
|
|
#endif
|
|
|
|
/**
|
|
* Check whether a hardware-accelerated CRC-32 implementation is
|
|
* supported on the current CPU.
|
|
*/
|
|
bool crc32_hw_supported();
|
|
|
|
/**
|
|
* Compute a CRC-32 checksum of a buffer using a portable,
|
|
* software-only implementation.
|
|
*
|
|
* @note This function is exposed to support special cases where the
|
|
* calling code is absolutely certain it wants to use the software
|
|
* implementation instead of the hardware-accelerated code - unit
|
|
* tests, for example. For all other scenarios, please call crc32()
|
|
* and let it pick an implementation based on the capabilities of
|
|
* the underlying CPU.
|
|
*/
|
|
uint32_t
|
|
crc32_sw(const uint8_t* data, size_t nbytes, uint32_t startingChecksum = ~0U);
|
|
|
|
/* See Checksum.h for details.
|
|
*
|
|
* crc2len *must* be a power of two >= 4.
|
|
*/
|
|
uint32_t crc32_combine_sw(uint32_t crc1, uint32_t crc2, size_t crc2len);
|
|
uint32_t crc32_combine_hw(uint32_t crc1, uint32_t crc2, size_t crc2len);
|
|
uint32_t crc32c_combine_sw(uint32_t crc1, uint32_t crc2, size_t crc2len);
|
|
uint32_t crc32c_combine_hw(uint32_t crc1, uint32_t crc2, size_t crc2len);
|
|
|
|
} // namespace detail
|
|
} // namespace folly
|