36 lines
801 B
C++
36 lines
801 B
C++
/*
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* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/.
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*
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* Copyright 2015 Danny Robson <danny@nerdcruft.net>
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*/
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#pragma once
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#include "../view.hpp"
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#include <cstddef>
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#include <cstdint>
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// Zilong Tan's FastHash, via George Marsaglia's "Xorshift RNGs"
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namespace cruft::hash {
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template <typename ValueT>
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struct fasthash {
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using digest_t = ValueT;
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static constexpr
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uint64_t mix (uint64_t v)
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{
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v ^= v >> 23;
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v *= 0x2127599bf4325c37;
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v ^= v >> 47;
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return v;
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}
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digest_t operator() (uint64_t seed, cruft::view<const uint8_t*>) const;
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};
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} |