| 1 | //
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| 2 | // Cforall Version 1.0.0 Copyright (C) 2022 University of Waterloo
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| 3 | //
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| 4 | // The contents of this file are covered under the licence agreement in the
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| 5 | // file "LICENCE" distributed with Cforall.
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| 6 | //
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| 7 | // random.hfa --
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| 8 | //
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| 9 | // Author : Peter A. Buhr
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| 10 | // Created On : Fri Jan 14 07:18:11 2022
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| 11 | // Last Modified By : Peter A. Buhr
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| 12 | // Last Modified On : Tue Dec 5 08:58:52 2023
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| 13 | // Update Count : 190
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| 14 | //
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| 15 |
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| 16 | #pragma once
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| 17 |
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| 18 | #include <stdint.h> // uintXX_t
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| 19 |
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| 20 | #define GLUE2( x, y ) x##y
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| 21 | #define GLUE( x, y ) GLUE2( x, y )
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| 22 |
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| 23 | // Set default PRNG for architecture size.
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| 24 | #if defined( __x86_64__ ) || defined( __aarch64__ ) // 64-bit architecture
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| 25 | // 64-bit generators
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| 26 | //#define LEHMER64
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| 27 | //#define XORSHIFT_12_25_27
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| 28 | #define XOSHIRO256PP
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| 29 | //#define KISS_64
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| 30 | // #define SPLITMIX_64
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| 31 |
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| 32 | // 32-bit generators
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| 33 | //#define XORSHIFT_6_21_7
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| 34 | #define XOSHIRO128PP
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| 35 | // #define SPLITMIX_32
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| 36 | #else // 32-bit architecture
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| 37 | // 64-bit generators
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| 38 | //#define XORSHIFT_13_7_17
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| 39 | #define XOSHIRO256PP
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| 40 | // #define SPLITMIX_64
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| 41 |
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| 42 | // 32-bit generators
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| 43 | //#define XORSHIFT_6_21_7
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| 44 | #define XOSHIRO128PP
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| 45 | // #define SPLITMIX_32
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| 46 | #endif
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| 47 |
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| 48 | // Define C/CFA PRNG name and random-state.
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| 49 |
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| 50 | #ifdef XOSHIRO256PP
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| 51 | #define PRNG_NAME_64 xoshiro256pp
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| 52 | #define PRNG_STATE_64_T GLUE(PRNG_NAME_64,_t)
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| 53 | typedef struct { uint64_t s0, s1, s2, s3; } PRNG_STATE_64_T;
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| 54 | #endif // XOSHIRO256PP
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| 55 |
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| 56 | #ifdef XOSHIRO128PP
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| 57 | #define PRNG_NAME_32 xoshiro128pp
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| 58 | #define PRNG_STATE_32_T GLUE(PRNG_NAME_32,_t)
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| 59 | typedef struct { uint32_t s0, s1, s2, s3; } PRNG_STATE_32_T;
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| 60 | #endif // XOSHIRO128PP
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| 61 |
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| 62 | #ifdef LEHMER64
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| 63 | #define PRNG_NAME_64 lehmer64
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| 64 | #define PRNG_STATE_64_T __uint128_t
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| 65 | #endif // LEHMER64
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| 66 |
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| 67 | #ifdef WYHASH64
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| 68 | #define PRNG_NAME_64 wyhash64
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| 69 | #define PRNG_STATE_64_T uint64_t
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| 70 | #endif // LEHMER64
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| 71 |
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| 72 | #ifdef XORSHIFT_13_7_17
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| 73 | #define PRNG_NAME_64 xorshift_13_7_17
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| 74 | #define PRNG_STATE_64_T uint64_t
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| 75 | #endif // XORSHIFT_13_7_17
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| 76 |
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| 77 | #ifdef XORSHIFT_6_21_7
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| 78 | #define PRNG_NAME_32 xorshift_6_21_7
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| 79 | #define PRNG_STATE_32_T uint32_t
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| 80 | #endif // XORSHIFT_6_21_7
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| 81 |
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| 82 | #ifdef XORSHIFT_12_25_27
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| 83 | #define PRNG_NAME_64 xorshift_12_25_27
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| 84 | #define PRNG_STATE_64_T uint64_t
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| 85 | #endif // XORSHIFT_12_25_27
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| 86 |
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| 87 | #ifdef SPLITMIX_64
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| 88 | #define PRNG_NAME_64 splitmix64
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| 89 | #define PRNG_STATE_64_T uint64_t
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| 90 | #endif // SPLITMIX32
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| 91 |
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| 92 | #ifdef SPLITMIX_32
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| 93 | #define PRNG_NAME_32 splitmix32
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| 94 | #define PRNG_STATE_32_T uint32_t
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| 95 | #endif // SPLITMIX32
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| 96 |
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| 97 | #ifdef KISS_64
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| 98 | #define PRNG_NAME_64 kiss_64
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| 99 | #define PRNG_STATE_64_T GLUE(PRNG_NAME_64,_t)
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| 100 | typedef struct { uint64_t z, w, jsr, jcong; } PRNG_STATE_64_T;
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| 101 | #endif // KISS_^64
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| 102 |
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| 103 | #ifdef XORWOW
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| 104 | #define PRNG_NAME_32 xorwow
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| 105 | #define PRNG_STATE_32_T GLUE(PRNG_NAME_32,_t)
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| 106 | typedef struct { uint32_t a, b, c, d, counter; } PRNG_STATE_32_T;
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| 107 | #endif // XOSHIRO128PP
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| 108 |
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| 109 | #define PRNG_SET_SEED_64 GLUE(PRNG_NAME_64,_set_seed)
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| 110 | #define PRNG_SET_SEED_32 GLUE(PRNG_NAME_32,_set_seed)
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| 111 |
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| 112 |
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| 113 | // Default PRNG used by runtime.
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| 114 | #if defined( __x86_64__ ) || defined( __aarch64__ ) // 64-bit architecture
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| 115 | #define PRNG_NAME PRNG_NAME_64
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| 116 | #define PRNG_STATE_T PRNG_STATE_64_T
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| 117 | #else // 32-bit architecture
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| 118 | #define PRNG_NAME PRNG_NAME_32
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| 119 | #define PRNG_STATE_T PRNG_STATE_32_T
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| 120 | #endif
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| 121 |
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| 122 | #define PRNG_SET_SEED GLUE(PRNG_NAME,_set_seed)
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| 123 |
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| 124 |
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| 125 | // ALL PRNG ALGORITHMS ARE OPTIMIZED SO THAT THE PRNG LOGIC CAN HAPPEN IN PARALLEL WITH THE USE OF THE RESULT.
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| 126 | // Specifically, the current random state is copied for returning, before computing the next value. As a consequence,
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| 127 | // the set_seed routine primes the PRNG by calling it with the state so the seed is not return as the first random
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| 128 | // value.
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| 129 |
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| 130 |
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| 131 | #ifdef __cforall // don't include in C code (invoke.h)
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| 132 |
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| 133 | // https://rosettacode.org/wiki/Pseudo-random_numbers/Splitmix64
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| 134 | //
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| 135 | // Splitmix64 is not recommended for demanding random number requirements, but is often used to calculate initial states
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| 136 | // for other more complex pseudo-random number generators (see https://prng.di.unimi.it).
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| 137 | // Also https://rosettacode.org/wiki/Pseudo-random_numbers/Splitmix64.
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| 138 | static inline uint64_t splitmix64( uint64_t & state ) {
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| 139 | state += 0x9e3779b97f4a7c15;
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| 140 | uint64_t z = state;
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| 141 | z = (z ^ (z >> 30)) * 0xbf58476d1ce4e5b9;
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| 142 | z = (z ^ (z >> 27)) * 0x94d049bb133111eb;
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| 143 | return z ^ (z >> 31);
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| 144 | } // splitmix64
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| 145 |
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| 146 | static inline void splitmix64_set_seed( uint64_t & state , uint64_t seed ) {
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| 147 | state = seed;
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| 148 | splitmix64( state ); // prime
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| 149 | } // splitmix64_set_seed
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| 150 |
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| 151 | // https://github.com/bryc/code/blob/master/jshash/PRNGs.md#splitmix32
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| 152 | //
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| 153 | // Splitmix32 is not recommended for demanding random number requirements, but is often used to calculate initial states
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| 154 | // for other more complex pseudo-random number generators (see https://prng.di.unimi.it).
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| 155 |
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| 156 | static inline uint32_t splitmix32( uint32_t & state ) {
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| 157 | state += 0x9e3779b9;
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| 158 | uint64_t z = state;
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| 159 | z = (z ^ (z >> 15)) * 0x85ebca6b;
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| 160 | z = (z ^ (z >> 13)) * 0xc2b2ae35;
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| 161 | return z ^ (z >> 16);
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| 162 | } // splitmix32
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| 163 |
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| 164 | static inline void splitmix32_set_seed( uint32_t & state, uint64_t seed ) {
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| 165 | state = seed;
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| 166 | splitmix32( state ); // prime
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| 167 | } // splitmix32_set_seed
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| 168 |
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| 169 | #ifdef __SIZEOF_INT128__
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| 170 | //--------------------------------------------------
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| 171 | static inline uint64_t lehmer64( __uint128_t & state ) {
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| 172 | __uint128_t ret = state;
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| 173 | state *= 0x_da94_2042_e4dd_58b5;
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| 174 | return ret >> 64;
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| 175 | } // lehmer64
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| 176 |
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| 177 | static inline void lehmer64_set_seed( __uint128_t & state, uint64_t seed ) {
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| 178 | // The seed needs to be coprime with the 2^64 modulus to get the largest period, so no factors of 2 in the seed.
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| 179 | state = splitmix64( seed ); // prime
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| 180 | } // lehmer64_set_seed
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| 181 |
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| 182 | //--------------------------------------------------
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| 183 | static inline uint64_t wyhash64( uint64_t & state ) {
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| 184 | uint64_t ret = state;
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| 185 | state += 0x_60be_e2be_e120_fc15;
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| 186 | __uint128_t tmp;
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| 187 | tmp = (__uint128_t) ret * 0x_a3b1_9535_4a39_b70d;
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| 188 | uint64_t m1 = (tmp >> 64) ^ tmp;
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| 189 | tmp = (__uint128_t)m1 * 0x_1b03_7387_12fa_d5c9;
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| 190 | uint64_t m2 = (tmp >> 64) ^ tmp;
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| 191 | return m2;
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| 192 | } // wyhash64
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| 193 |
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| 194 | static inline void wyhash64_set_seed( uint64_t & state, uint64_t seed ) {
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| 195 | state = splitmix64( seed ); // prime
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| 196 | } // wyhash64_set_seed
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| 197 | #endif // __SIZEOF_INT128__
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| 198 |
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| 199 | // https://prng.di.unimi.it/xoshiro256starstar.c
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| 200 | //
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| 201 | // This is xoshiro256++ 1.0, one of our all-purpose, rock-solid generators. It has excellent (sub-ns) speed, a state
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| 202 | // (256 bits) that is large enough for any parallel application, and it passes all tests we are aware of.
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| 203 | //
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| 204 | // For generating just floating-point numbers, xoshiro256+ is even faster.
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| 205 | //
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| 206 | // The state must be seeded so that it is not everywhere zero. If you have a 64-bit seed, we suggest to seed a
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| 207 | // splitmix64 generator and use its output to fill s.
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| 208 |
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| 209 | #ifndef XOSHIRO256PP
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| 210 | typedef struct { uint64_t s0, s1, s2, s3; } xoshiro256pp_t;
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| 211 | #endif // ! XOSHIRO256PP
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| 212 |
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| 213 | static inline uint64_t xoshiro256pp( xoshiro256pp_t & rs ) with(rs) {
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| 214 | inline uint64_t rotl( const uint64_t x, int k ) {
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| 215 | return (x << k) | (x >> (64 - k));
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| 216 | } // rotl
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| 217 |
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| 218 | const uint64_t result = rotl( s0 + s3, 23 ) + s0;
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| 219 | const uint64_t t = s1 << 17;
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| 220 |
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| 221 | s2 ^= s0;
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| 222 | s3 ^= s1;
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| 223 | s1 ^= s2;
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| 224 | s0 ^= s3;
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| 225 | s2 ^= t;
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| 226 | s3 = rotl( s3, 45 );
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| 227 | return result;
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| 228 | } // xoshiro256pp
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| 229 |
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| 230 | static inline void xoshiro256pp_set_seed( xoshiro256pp_t & state, uint64_t seed ) {
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| 231 | // To attain repeatable seeding, compute seeds separately because the order of argument evaluation is undefined.
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| 232 | uint64_t seed1 = splitmix64( seed ); // prime
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| 233 | uint64_t seed2 = splitmix64( seed );
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| 234 | uint64_t seed3 = splitmix64( seed );
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| 235 | uint64_t seed4 = splitmix64( seed );
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| 236 | state = (xoshiro256pp_t){ seed1, seed2, seed3, seed4 };
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| 237 | } // xoshiro256pp_set_seed
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| 238 |
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| 239 | // https://prng.di.unimi.it/xoshiro128plusplus.c
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| 240 | //
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| 241 | // This is xoshiro128++ 1.0, one of our 32-bit all-purpose, rock-solid generators. It has excellent speed, a state size
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| 242 | // (128 bits) that is large enough for mild parallelism, and it passes all tests we are aware of.
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| 243 | //
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| 244 | // For generating just single-precision (i.e., 32-bit) floating-point numbers, xoshiro128+ is even faster.
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| 245 | //
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| 246 | // The state must be seeded so that it is not everywhere zero.
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| 247 |
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| 248 | #ifndef XOSHIRO128PP
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| 249 | typedef struct { uint32_t s0, s1, s2, s3; } xoshiro128pp_t;
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| 250 | #endif // ! XOSHIRO128PP
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| 251 |
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| 252 | static inline uint32_t xoshiro128pp( xoshiro128pp_t & rs ) with(rs) {
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| 253 | inline uint32_t rotl( const uint32_t x, int k ) {
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| 254 | return (x << k) | (x >> (32 - k));
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| 255 | } // rotl
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| 256 |
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| 257 | const uint32_t result = rotl( s0 + s3, 7 ) + s0;
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| 258 | const uint32_t t = s1 << 9;
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| 259 |
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| 260 | s2 ^= s0;
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| 261 | s3 ^= s1;
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| 262 | s1 ^= s2;
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| 263 | s0 ^= s3;
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| 264 | s2 ^= t;
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| 265 | s3 = rotl( s3, 11 );
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| 266 | return result;
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| 267 | } // xoshiro128pp
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| 268 |
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| 269 | static inline void xoshiro128pp_set_seed( xoshiro128pp_t & state, uint32_t seed ) {
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| 270 | // To attain repeatable seeding, compute seeds separately because the order of argument evaluation is undefined.
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| 271 | uint32_t seed1 = splitmix32( seed ); // prime
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| 272 | uint32_t seed2 = splitmix32( seed );
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| 273 | uint32_t seed3 = splitmix32( seed );
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| 274 | uint32_t seed4 = splitmix32( seed );
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| 275 | state = (xoshiro128pp_t){ seed1, seed2, seed3, seed4 };
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| 276 | } // xoshiro128pp_set_seed
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| 277 |
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| 278 | //--------------------------------------------------
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| 279 | static inline uint64_t xorshift_13_7_17( uint64_t & state ) {
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| 280 | uint64_t ret = state;
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| 281 | state ^= state << 13;
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| 282 | state ^= state >> 7;
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| 283 | state ^= state << 17;
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| 284 | return ret;
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| 285 | } // xorshift_13_7_17
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| 286 |
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| 287 | static inline void xorshift_13_7_17_set_seed( uint64_t & state, uint64_t seed ) {
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| 288 | state = splitmix64( seed ); // prime
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| 289 | } // xorshift_13_7_17_set_seed
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| 290 |
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| 291 | //--------------------------------------------------
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| 292 | // Marsaglia shift-XOR PRNG with thread-local state
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| 293 | // Period is 4G-1
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| 294 | // 0 is absorbing and must be avoided
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| 295 | // Low-order bits are not particularly random
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| 296 | static inline uint32_t xorshift_6_21_7( uint32_t & state ) {
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| 297 | uint32_t ret = state;
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| 298 | state ^= state << 6;
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| 299 | state ^= state >> 21;
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| 300 | state ^= state << 7;
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| 301 | return ret;
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| 302 | } // xorshift_6_21_7
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| 303 |
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| 304 | static inline void xorshift_6_21_7_set_seed( uint32_t & state, uint32_t seed ) {
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| 305 | state = splitmix32( seed ); // prime
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| 306 | } // xorshift_6_21_7_set_seed
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| 307 |
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| 308 | //--------------------------------------------------
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| 309 | // The state must be seeded with a nonzero value.
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| 310 | static inline uint64_t xorshift_12_25_27( uint64_t & state ) {
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| 311 | uint64_t ret = state;
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| 312 | state ^= state >> 12;
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| 313 | state ^= state << 25;
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| 314 | state ^= state >> 27;
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| 315 | return ret * 0x_2545_F491_4F6C_DD1D;
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| 316 | } // xorshift_12_25_27
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| 317 |
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| 318 | static inline void xorshift_12_25_27_set_seed( uint64_t & state, uint64_t seed ) {
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| 319 | state = splitmix64( seed ); // prime
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| 320 | } // xorshift_12_25_27_set_seed
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| 321 |
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| 322 | //--------------------------------------------------
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| 323 | // The state must be seeded with a nonzero value.
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| 324 | #ifndef KISS_64
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| 325 | typedef struct { uint64_t z, w, jsr, jcong; } kiss_64_t;
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| 326 | #endif // ! KISS_64
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| 327 |
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| 328 | static inline uint64_t kiss_64( kiss_64_t & rs ) with(rs) {
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| 329 | kiss_64_t ret = rs;
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| 330 | z = 36969 * (z & 65535) + (z >> 16);
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| 331 | w = 18000 * (w & 65535) + (w >> 16);
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| 332 | jsr ^= (jsr << 13);
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| 333 | jsr ^= (jsr >> 17);
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| 334 | jsr ^= (jsr << 5);
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| 335 | jcong = 69069 * jcong + 1234567;
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| 336 | return (((ret.z << 16) + ret.w) ^ ret.jcong) + ret.jsr;
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| 337 | } // kiss_64
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| 338 |
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| 339 | static inline void kiss_64_set_seed( kiss_64_t & rs, uint64_t seed ) with(rs) {
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| 340 | z = 1; w = 1; jsr = 4; jcong = splitmix64( seed ); // prime
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| 341 | } // kiss_64_set_seed
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| 342 |
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| 343 | //--------------------------------------------------
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| 344 | // The state array must be initialized to non-zero in the first four words.
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| 345 | #ifndef XORWOW
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| 346 | typedef struct { uint32_t a, b, c, d, counter; } xorwow_t;
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| 347 | #endif // ! XORWOW
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| 348 |
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| 349 | static inline uint32_t xorwow( xorwow_t & rs ) with(rs) {
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| 350 | // Algorithm "xorwow" from p. 5 of Marsaglia, "Xorshift RNGs".
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| 351 | uint32_t ret = a + counter;
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| 352 | uint32_t t = d;
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| 353 |
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| 354 | uint32_t const s = a;
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| 355 | d = c;
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| 356 | c = b;
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| 357 | b = s;
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| 358 |
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| 359 | t ^= t >> 2;
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| 360 | t ^= t << 1;
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| 361 | t ^= s ^ (s << 4);
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| 362 | a = t;
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| 363 | counter += 362437;
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| 364 | return ret;
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| 365 | } // xorwow
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| 366 |
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| 367 | static inline void xorwow_set_seed( xorwow_t & rs, uint32_t seed ) {
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| 368 | // To attain repeatable seeding, compute seeds separately because the order of argument evaluation is undefined.
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| 369 | uint32_t seed1 = splitmix32( seed ); // prime
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| 370 | uint32_t seed2 = splitmix32( seed );
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| 371 | uint32_t seed3 = splitmix32( seed );
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| 372 | uint32_t seed4 = splitmix32( seed );
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| 373 | rs = (xorwow_t){ seed1, seed2, seed3, seed4, 0 };
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| 374 | } // xorwow_set_seed
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| 375 |
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| 376 | //--------------------------------------------------
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| 377 | // Used in __tls_rand_fwd
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| 378 | #define M (1_l64u << 48_l64u)
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| 379 | #define A (25_214_903_917_l64u)
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| 380 | #define AI (18_446_708_753_438_544_741_l64u)
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| 381 | #define C (11_l64u)
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| 382 | #define D (16_l64u)
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| 383 |
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| 384 | // Bi-directional LCG random-number generator
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| 385 | static inline uint32_t LCGBI_fwd( uint64_t & rs ) {
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| 386 | rs = (A * rs + C) & (M - 1);
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| 387 | return rs >> D;
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| 388 | } // LCGBI_fwd
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| 389 |
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| 390 | static inline uint32_t LCGBI_bck( uint64_t & rs ) {
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| 391 | unsigned int r = rs >> D;
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| 392 | rs = AI * (rs - C) & (M - 1);
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| 393 | return r;
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| 394 | } // LCGBI_bck
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| 395 |
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| 396 | #undef M
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| 397 | #undef A
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| 398 | #undef AI
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| 399 | #undef C
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| 400 | #undef D
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| 401 |
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| 402 | #endif // __cforall
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