Algorithms.h

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/*
 * MIT License
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#pragma once
 
#include <cstdint>
 
#include "Concepts.h"
#include "Constants.h"
 
namespace nfx::hashing
{
    //=====================================================================
    // Low - level hash building blocks
    //=====================================================================
 
    //----------------------------------------------
    // Hash algorithm primitives
    //----------------------------------------------

    template <Hash32or64 HashType = uint32_t>
    [[nodiscard]] inline constexpr HashType larson( HashType hash, uint8_t ch ) noexcept;

    template <
        Hash32or64 HashType = uint32_t,
        uint64_t FnvPrime = ( sizeof( HashType ) == 4 ? constants::FNV_PRIME_32 : constants::FNV_PRIME_64 )>
    [[nodiscard]] inline constexpr HashType fnv1a( HashType hash, uint8_t ch ) noexcept;

    [[nodiscard]] inline uint32_t crc32c( uint32_t hash, uint8_t ch ) noexcept;

    [[nodiscard]] inline constexpr uint32_t crc32cSoft( uint32_t hash, uint8_t ch ) noexcept;
 
    //----------------------------------------------
    // Seed and bit mixing
    //----------------------------------------------

    template <Hash32or64 HashType = uint32_t, uint64_t MixConstant = constants::SEED_MIX_MULTIPLIER_64>
    [[nodiscard]] inline constexpr HashType seedMix( HashType seed, HashType hash, uint64_t size ) noexcept;
 
    //----------------------------------------------
    // Hash combination
    //----------------------------------------------

    template <Hash32or64 HashType = uint32_t>
    [[nodiscard]] inline constexpr HashType combine( HashType existingHash, HashType newHash, HashType prime ) noexcept;

    template <Hash32or64 HashType = uint32_t>
    [[nodiscard]] inline constexpr HashType combine( HashType existingHash, HashType newHash ) noexcept;
} // namespace nfx::hashing
 
#include "nfx/detail/hashing/Algorithms.inl"