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-rw-r--r--src/test/util/xoroshiro128plusplus.h71
1 files changed, 0 insertions, 71 deletions
diff --git a/src/test/util/xoroshiro128plusplus.h b/src/test/util/xoroshiro128plusplus.h
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--- a/src/test/util/xoroshiro128plusplus.h
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@@ -1,71 +0,0 @@
-// Copyright (c) 2022 The Bitcoin Core developers
-// Distributed under the MIT software license, see the accompanying
-// file COPYING or http://www.opensource.org/licenses/mit-license.php.
-
-#ifndef BITCOIN_TEST_UTIL_XOROSHIRO128PLUSPLUS_H
-#define BITCOIN_TEST_UTIL_XOROSHIRO128PLUSPLUS_H
-
-#include <cstdint>
-#include <limits>
-
-/** xoroshiro128++ PRNG. Extremely fast, not appropriate for cryptographic purposes.
- *
- * Memory footprint is 128bit, period is 2^128 - 1.
- * This class is not thread-safe.
- *
- * Reference implementation available at https://prng.di.unimi.it/xoroshiro128plusplus.c
- * See https://prng.di.unimi.it/
- */
-class XoRoShiRo128PlusPlus
-{
- uint64_t m_s0;
- uint64_t m_s1;
-
- [[nodiscard]] constexpr static uint64_t rotl(uint64_t x, int n)
- {
- return (x << n) | (x >> (64 - n));
- }
-
- [[nodiscard]] constexpr static uint64_t SplitMix64(uint64_t& seedval) noexcept
- {
- uint64_t z = (seedval += UINT64_C(0x9e3779b97f4a7c15));
- z = (z ^ (z >> 30U)) * UINT64_C(0xbf58476d1ce4e5b9);
- z = (z ^ (z >> 27U)) * UINT64_C(0x94d049bb133111eb);
- return z ^ (z >> 31U);
- }
-
-public:
- using result_type = uint64_t;
-
- constexpr explicit XoRoShiRo128PlusPlus(uint64_t seedval) noexcept
- : m_s0(SplitMix64(seedval)), m_s1(SplitMix64(seedval))
- {
- }
-
- // no copy - that is dangerous, we don't want accidentally copy the RNG and then have two streams
- // with exactly the same results. If you need a copy, call copy().
- XoRoShiRo128PlusPlus(const XoRoShiRo128PlusPlus&) = delete;
- XoRoShiRo128PlusPlus& operator=(const XoRoShiRo128PlusPlus&) = delete;
-
- // allow moves
- XoRoShiRo128PlusPlus(XoRoShiRo128PlusPlus&&) = default;
- XoRoShiRo128PlusPlus& operator=(XoRoShiRo128PlusPlus&&) = default;
-
- ~XoRoShiRo128PlusPlus() = default;
-
- constexpr result_type operator()() noexcept
- {
- uint64_t s0 = m_s0, s1 = m_s1;
- const uint64_t result = rotl(s0 + s1, 17) + s0;
- s1 ^= s0;
- m_s0 = rotl(s0, 49) ^ s1 ^ (s1 << 21);
- m_s1 = rotl(s1, 28);
- return result;
- }
-
- static constexpr result_type min() noexcept { return std::numeric_limits<result_type>::min(); }
- static constexpr result_type max() noexcept { return std::numeric_limits<result_type>::max(); }
- static constexpr double entropy() noexcept { return 0.0; }
-};
-
-#endif // BITCOIN_TEST_UTIL_XOROSHIRO128PLUSPLUS_H