2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
6 Stockfish is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 Stockfish is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
30 using namespace std::chrono;
34 /// Version number. If Version is left empty, then compile date in the format
35 /// DD-MM-YY and show in engine_info.
36 const string Version = "";
39 int64_t hits[2], means[2];
41 /// Our fancy logging facility. The trick here is to replace cin.rdbuf() and
42 /// cout.rdbuf() with two Tie objects that tie cin and cout to a file stream. We
43 /// can toggle the logging of std::cout and std:cin at runtime whilst preserving
44 /// usual i/o functionality, all without changing a single line of code!
45 /// Idea from http://groups.google.com/group/comp.lang.c++/msg/1d941c0f26ea0d81
47 struct Tie: public streambuf { // MSVC requires splitted streambuf for cin and cout
49 Tie(streambuf* b, ofstream* f) : buf(b), file(f) {}
51 int sync() { return file->rdbuf()->pubsync(), buf->pubsync(); }
52 int overflow(int c) { return log(buf->sputc((char)c), "<< "); }
53 int underflow() { return buf->sgetc(); }
54 int uflow() { return log(buf->sbumpc(), ">> "); }
59 int log(int c, const char* prefix) {
61 static int last = '\n';
64 file->rdbuf()->sputn(prefix, 3);
66 return last = file->rdbuf()->sputc((char)c);
72 Logger() : in(cin.rdbuf(), &file), out(cout.rdbuf(), &file) {}
73 ~Logger() { start(false); }
79 static void start(bool b) {
83 if (b && !l.file.is_open())
85 l.file.open("io_log.txt", ifstream::out | ifstream::app);
89 else if (!b && l.file.is_open())
91 cout.rdbuf(l.out.buf);
100 /// engine_info() returns the full name of the current Stockfish version. This
101 /// will be either "Stockfish <Tag> DD-MM-YY" (where DD-MM-YY is the date when
102 /// the program was compiled) or "Stockfish <Version>", depending on whether
103 /// Version is empty.
105 const string engine_info(bool to_uci) {
107 const string months("Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec");
108 string month, day, year;
109 stringstream ss, date(__DATE__); // From compiler, format is "Sep 21 2008"
111 ss << "Stockfish " << Version << setfill('0');
115 date >> month >> day >> year;
116 ss << setw(2) << day << setw(2) << (1 + months.find(month) / 4) << year.substr(2);
119 ss << (Is64Bit ? " 64" : "")
120 << (HasPext ? " BMI2" : (HasPopCnt ? " POPCNT" : ""))
121 << (to_uci ? "\nid author ": " by ")
122 << "Tord Romstad, Marco Costalba and Joona Kiiski";
128 /// Convert system time to milliseconds. That's all we need.
130 Time::point Time::now() {
131 return duration_cast<milliseconds>(steady_clock::now().time_since_epoch()).count();
135 /// Debug functions used mainly to collect run-time statistics
137 void dbg_hit_on(bool b) { ++hits[0]; if (b) ++hits[1]; }
138 void dbg_hit_on(bool c, bool b) { if (c) dbg_hit_on(b); }
139 void dbg_mean_of(int v) { ++means[0]; means[1] += v; }
144 cerr << "Total " << hits[0] << " Hits " << hits[1]
145 << " hit rate (%) " << 100 * hits[1] / hits[0] << endl;
148 cerr << "Total " << means[0] << " Mean "
149 << (double)means[1] / means[0] << endl;
153 /// Used to serialize access to std::cout to avoid multiple threads writing at
156 std::ostream& operator<<(std::ostream& os, SyncCout sc) {
170 /// Trampoline helper to avoid moving Logger to misc.h
171 void start_logger(bool b) { Logger::start(b); }
174 /// prefetch() preloads the given address in L1/L2 cache. This is a non-blocking
175 /// function that doesn't stall the CPU waiting for data to be loaded from memory,
176 /// which can be quite slow.
179 void prefetch(void*) {}
183 void prefetch(void* addr) {
185 # if defined(__INTEL_COMPILER)
186 // This hack prevents prefetches from being optimized away by
187 // Intel compiler. Both MSVC and gcc seem not be affected by this.
191 # if defined(__INTEL_COMPILER) || defined(_MSC_VER)
192 _mm_prefetch((char*)addr, _MM_HINT_T0);
194 __builtin_prefetch(addr);