2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
5 Stockfish is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
10 Stockfish is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
19 #ifndef MISC_H_INCLUDED
20 #define MISC_H_INCLUDED
30 const std::string engine_info(bool to_uci = false);
31 const std::string compiler_info();
32 void prefetch(void* addr);
33 void start_logger(const std::string& fname);
34 void* std_aligned_alloc(size_t alignment, size_t size);
35 void std_aligned_free(void* ptr);
36 void* aligned_ttmem_alloc(size_t size, void*& mem);
37 void aligned_ttmem_free(void* mem); // nop if mem == nullptr
39 void dbg_hit_on(bool b);
40 void dbg_hit_on(bool c, bool b);
41 void dbg_mean_of(int v);
44 typedef std::chrono::milliseconds::rep TimePoint; // A value in milliseconds
46 static_assert(sizeof(TimePoint) == sizeof(int64_t), "TimePoint should be 64 bits");
48 inline TimePoint now() {
49 return std::chrono::duration_cast<std::chrono::milliseconds>
50 (std::chrono::steady_clock::now().time_since_epoch()).count();
53 template<class Entry, int Size>
55 Entry* operator[](Key key) { return &table[(uint32_t)key & (Size - 1)]; }
58 std::vector<Entry> table = std::vector<Entry>(Size); // Allocate on the heap
62 enum SyncCout { IO_LOCK, IO_UNLOCK };
63 std::ostream& operator<<(std::ostream&, SyncCout);
65 #define sync_cout std::cout << IO_LOCK
66 #define sync_endl std::endl << IO_UNLOCK
70 /// Clamp a value between lo and hi. Available in c++17.
71 template<class T> constexpr const T& clamp(const T& v, const T& lo, const T& hi) {
72 return v < lo ? lo : v > hi ? hi : v;
77 /// xorshift64star Pseudo-Random Number Generator
78 /// This class is based on original code written and dedicated
79 /// to the public domain by Sebastiano Vigna (2014).
80 /// It has the following characteristics:
82 /// - Outputs 64-bit numbers
83 /// - Passes Dieharder and SmallCrush test batteries
84 /// - Does not require warm-up, no zeroland to escape
85 /// - Internal state is a single 64-bit integer
86 /// - Period is 2^64 - 1
87 /// - Speed: 1.60 ns/call (Core i7 @3.40GHz)
89 /// For further analysis see
90 /// <http://vigna.di.unimi.it/ftp/papers/xorshift.pdf>
98 s ^= s >> 12, s ^= s << 25, s ^= s >> 27;
99 return s * 2685821657736338717LL;
103 PRNG(uint64_t seed) : s(seed) { assert(seed); }
105 template<typename T> T rand() { return T(rand64()); }
107 /// Special generator used to fast init magic numbers.
108 /// Output values only have 1/8th of their bits set on average.
109 template<typename T> T sparse_rand()
110 { return T(rand64() & rand64() & rand64()); }
113 inline uint64_t mul_hi64(uint64_t a, uint64_t b) {
114 #if defined(__GNUC__) && defined(IS_64BIT)
115 __extension__ typedef unsigned __int128 uint128;
116 return ((uint128)a * (uint128)b) >> 64;
118 uint64_t aL = (uint32_t)a, aH = a >> 32;
119 uint64_t bL = (uint32_t)b, bH = b >> 32;
120 uint64_t c1 = (aL * bL) >> 32;
121 uint64_t c2 = aH * bL + c1;
122 uint64_t c3 = aL * bH + (uint32_t)c2;
123 return aH * bH + (c2 >> 32) + (c3 >> 32);
127 /// Under Windows it is not possible for a process to run on more than one
128 /// logical processor group. This usually means to be limited to use max 64
129 /// cores. To overcome this, some special platform specific API should be
130 /// called to set group affinity for each thread. Original code from Texel by
131 /// Peter Ă–sterlund.
133 namespace WinProcGroup {
134 void bindThisThread(size_t idx);
137 #endif // #ifndef MISC_H_INCLUDED