X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Frkiss.h;fp=src%2Frkiss.h;h=0000000000000000000000000000000000000000;hp=f3468db4e0f056edede0914c5a9d7cde72ea0bba;hb=158864270a055fe20dca4a87f4b7a8aa9cedfeb9;hpb=a87da2c4b3dce975fa8642c352c99aed5a1420f8 diff --git a/src/rkiss.h b/src/rkiss.h deleted file mode 100644 index f3468db4..00000000 --- a/src/rkiss.h +++ /dev/null @@ -1,81 +0,0 @@ -/* - Stockfish, a UCI chess playing engine derived from Glaurung 2.1 - Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad - - Stockfish is free software: you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation, either version 3 of the License, or - (at your option) any later version. - - Stockfish is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program. If not, see . - - This file is based on original code by Heinz van Saanen and is - available under the GNU General Public License as published by - the Free Software Foundation, either version 3 of the License, or - (at your option) any later version. -*/ - -#ifndef RKISS_H_INCLUDED -#define RKISS_H_INCLUDED - -#include "types.h" - -/// RKISS is our pseudo random number generator (PRNG) used to compute hash keys. -/// George Marsaglia invented the RNG-Kiss-family in the early 90's. This is a -/// specific version that Heinz van Saanen derived from some public domain code -/// by Bob Jenkins. Following the feature list, as tested by Heinz. -/// -/// - Quite platform independent -/// - Passes ALL dieharder tests! Here *nix sys-rand() e.g. fails miserably:-) -/// - ~12 times faster than my *nix sys-rand() -/// - ~4 times faster than SSE2-version of Mersenne twister -/// - Average cycle length: ~2^126 -/// - 64 bit seed -/// - Return doubles with a full 53 bit mantissa -/// - Thread safe - -class RKISS { - - uint64_t a, b, c, d; - - uint64_t rotate_L(uint64_t x, unsigned k) const { - return (x << k) | (x >> (64 - k)); - } - - uint64_t rand64() { - - const uint64_t e = a - rotate_L(b, 7); - a = b ^ rotate_L(c, 13); - b = c + rotate_L(d, 37); - c = d + e; - return d = e + a; - } - -public: - RKISS(int seed = 73) { - - a = 0xF1EA5EED, b = c = d = 0xD4E12C77; - - for (int i = 0; i < seed; ++i) // Scramble a few rounds - rand64(); - } - - template T rand() { return T(rand64()); } - - /// Special generator used to fast init magic numbers. Here the - /// trick is to rotate the randoms of a given quantity 's' known - /// to be optimal to quickly find a good magic candidate. - template T magic_rand(int s) { - return rotate_L(rotate_L(rand(), (s >> 0) & 0x3F) & rand() - , (s >> 6) & 0x3F) & rand(); - } -}; - -#endif // #ifndef RKISS_H_INCLUDED