![]() Remove from the search this special case and apply null search and razoring also in mate positions. Tested in no-regression mode and passed both STC LLR: 2.96 (-2.94,2.94) [-3.00,1.00] Total: 65431 W: 10860 L: 10810 D: 43761 and LTC LLR: 2.95 (-2.94,2.94) [-3.00,1.00] Total: 34928 W: 4814 L: 4713 D: 25401 This patch kicks in only in mate positions and in these cases it seems beneficial in finding mates faster as Yery Spark measured on the Chest mate suite: Total number of positions 6425 Fixed nodes 200K per position master: 1049 new: 1154 And also the 5446 'hard' positions again with 2000K nodes (those not found by both engines in 200K nodes): master: 1069 new: 1395 bench: 7710548 |
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src | ||
Copying.txt | ||
Readme.md |
Overview
Stockfish is a free UCI chess engine derived from Glaurung 2.1. It is not a complete chess program and requires some UCI-compatible GUI (e.g. XBoard with PolyGlot, eboard, Arena, Sigma Chess, Shredder, Chess Partner or Fritz) in order to be used comfortably. Read the documentation for your GUI of choice for information about how to use Stockfish with it.
This version of Stockfish supports up to 128 cores. The engine defaults to one search thread, so it is therefore recommended to inspect the value of the Threads UCI parameter, and to make sure it equals the number of CPU cores on your computer.
Files
This distribution of Stockfish consists of the following files:
-
Readme.md, the file you are currently reading.
-
Copying.txt, a text file containing the GNU General Public License.
-
src, a subdirectory containing the full source code, including a Makefile that can be used to compile Stockfish on Unix-like systems.
Compiling it yourself
On Unix-like systems, it should be possible to compile Stockfish directly from the source code with the included Makefile.
Stockfish has support for 32 or 64-bit CPUs, the hardware POPCNT instruction, big-endian machines such as Power PC, and other platforms.
In general it is recommended to run make help
to see a list of make
targets with corresponding descriptions. When not using the Makefile to
compile (for instance with Microsoft MSVC) you need to manually
set/unset some switches in the compiler command line; see file types.h
for a quick reference.
Terms of use
Stockfish is free, and distributed under the GNU General Public License (GPL). Essentially, this means that you are free to do almost exactly what you want with the program, including distributing it among your friends, making it available for download from your web site, selling it (either by itself or as part of some bigger software package), or using it as the starting point for a software project of your own.
The only real limitation is that whenever you distribute Stockfish in some way, you must always include the full source code, or a pointer to where the source code can be found. If you make any changes to the source code, these changes must also be made available under the GPL.
For full details, read the copy of the GPL found in the file named Copying.txt