2008-08-31 23:59:13 -06:00
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/*
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2008-10-19 10:56:28 -06:00
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Stockfish, a UCI chess playing engine derived from Glaurung 2.1
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2021-01-08 09:04:23 -07:00
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Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
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2008-08-31 23:59:13 -06:00
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2008-10-19 10:56:28 -06:00
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Stockfish is free software: you can redistribute it and/or modify
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2008-08-31 23:59:13 -06:00
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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2008-09-06 04:30:07 -06:00
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2008-10-19 10:56:28 -06:00
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Stockfish is distributed in the hope that it will be useful,
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2008-08-31 23:59:13 -06:00
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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2008-09-06 04:30:07 -06:00
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2008-08-31 23:59:13 -06:00
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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2014-12-30 02:31:50 -07:00
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#include <cstring> // For std::memset
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2011-01-07 05:00:25 -07:00
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#include <iostream>
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2018-05-14 11:52:21 -06:00
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#include <thread>
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2008-08-31 23:59:13 -06:00
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2012-07-07 12:30:27 -06:00
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#include "bitboard.h"
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2018-05-14 11:52:21 -06:00
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#include "misc.h"
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2018-12-08 15:03:42 -07:00
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#include "thread.h"
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2008-08-31 23:59:13 -06:00
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#include "tt.h"
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2018-05-14 11:52:21 -06:00
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#include "uci.h"
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2008-08-31 23:59:13 -06:00
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2021-02-26 02:02:13 -07:00
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namespace Stockfish {
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2011-04-15 10:14:12 -06:00
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TranspositionTable TT; // Our global transposition table
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2008-08-31 23:59:13 -06:00
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2020-06-24 14:19:58 -06:00
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/// TTEntry::save() populates the TTEntry with a new node's data, possibly
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2019-01-01 06:13:08 -07:00
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/// overwriting an old position. Update is not atomic and can be racy.
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void TTEntry::save(Key k, Value v, bool pv, Bound b, Depth d, Move m, Value ev) {
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2018-07-03 16:58:16 -06:00
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// Preserve any existing move for the same position
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Use 128 bit multiply for TT index
Remove super cluster stuff from TT and just use a 128 bit multiply.
STC https://tests.stockfishchess.org/tests/view/5ee719b3aae8aec816ab7548
LLR: 2.94 (-2.94,2.94) {-1.50,0.50}
Total: 12736 W: 2502 L: 2333 D: 7901
Ptnml(0-2): 191, 1452, 2944, 1559, 222
LTC https://tests.stockfishchess.org/tests/view/5ee732d1aae8aec816ab7556
LLR: 2.93 (-2.94,2.94) {-1.50,0.50}
Total: 27584 W: 3431 L: 3350 D: 20803
Ptnml(0-2): 173, 2500, 8400, 2511, 208
Scheme back to being derived from https://lemire.me/blog/2016/06/27/a-fast-alternative-to-the-modulo-reduction/
Also the default optimized version of the index calculation now uses fewer instructions.
https://godbolt.org/z/Tktxbv
Might benefit from mulx (requires -mbmi2)
closes https://github.com/official-stockfish/Stockfish/pull/2744
bench: 4320954
2020-06-15 00:35:07 -06:00
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if (m || (uint16_t)k != key16)
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2018-07-03 16:58:16 -06:00
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move16 = (uint16_t)m;
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Allow TT entries with key16==0 to be fetched
Fix the issue where a TT entry with key16==0 would always be reported
as a miss. Instead, we'll use depth8 to detect whether the TT entry is
occupied. In order to do that, we'll change DEPTH_OFFSET to -7
(depth8==0) to distinguish between an unoccupied entry and the
otherwise lowest possible depth, i.e., DEPTH_NONE (depth8==1).
To prevent a performance regression, we'll reorder the TT entry fields
by the access order of TranspositionTable::probe(). Memory in general
works fastest when accessed in sequential order. We'll also match the
store order in TTEntry::save() with the entry field order, and
re-order the 'if-or' expressions in TTEntry::save() from the cheapest
to the most expensive.
Finally, as we now have a proper TT entry occupancy test, we'll fix a
minor corner case with hashfull reporting. To reproduce:
- Use a big hash
- Either:
a. Start 31 very quick searches (this wraparounds generation to 0); or
b. Force generation of the first search to 0.
- go depth infinite
Before the fix, hashfull would incorrectly report nearly full hash
immediately after the search start, since
TranspositionTable::hashfull() used to consider only the entry
generation and not whether the entry was actually occupied.
STC:
LLR: 2.95 (-2.94,2.94) {-0.25,1.25}
Total: 36848 W: 4091 L: 3898 D: 28859
Ptnml(0-2): 158, 2996, 11972, 3091, 207
https://tests.stockfishchess.org/tests/view/5f3f98d5dc02a01a0c2881f7
LTC:
LLR: 2.95 (-2.94,2.94) {0.25,1.25}
Total: 32280 W: 1828 L: 1653 D: 28799
Ptnml(0-2): 34, 1428, 13051, 1583, 44
https://tests.stockfishchess.org/tests/view/5f3fe77a87a5c3c63d8f5332
closes https://github.com/official-stockfish/Stockfish/pull/3048
Bench: 3760677
2020-08-21 03:12:39 -06:00
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// Overwrite less valuable entries (cheapest checks first)
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if (b == BOUND_EXACT
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|| (uint16_t)k != key16
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|| d - DEPTH_OFFSET > depth8 - 4)
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2018-07-03 16:58:16 -06:00
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{
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Allow TT entries with key16==0 to be fetched
Fix the issue where a TT entry with key16==0 would always be reported
as a miss. Instead, we'll use depth8 to detect whether the TT entry is
occupied. In order to do that, we'll change DEPTH_OFFSET to -7
(depth8==0) to distinguish between an unoccupied entry and the
otherwise lowest possible depth, i.e., DEPTH_NONE (depth8==1).
To prevent a performance regression, we'll reorder the TT entry fields
by the access order of TranspositionTable::probe(). Memory in general
works fastest when accessed in sequential order. We'll also match the
store order in TTEntry::save() with the entry field order, and
re-order the 'if-or' expressions in TTEntry::save() from the cheapest
to the most expensive.
Finally, as we now have a proper TT entry occupancy test, we'll fix a
minor corner case with hashfull reporting. To reproduce:
- Use a big hash
- Either:
a. Start 31 very quick searches (this wraparounds generation to 0); or
b. Force generation of the first search to 0.
- go depth infinite
Before the fix, hashfull would incorrectly report nearly full hash
immediately after the search start, since
TranspositionTable::hashfull() used to consider only the entry
generation and not whether the entry was actually occupied.
STC:
LLR: 2.95 (-2.94,2.94) {-0.25,1.25}
Total: 36848 W: 4091 L: 3898 D: 28859
Ptnml(0-2): 158, 2996, 11972, 3091, 207
https://tests.stockfishchess.org/tests/view/5f3f98d5dc02a01a0c2881f7
LTC:
LLR: 2.95 (-2.94,2.94) {0.25,1.25}
Total: 32280 W: 1828 L: 1653 D: 28799
Ptnml(0-2): 34, 1428, 13051, 1583, 44
https://tests.stockfishchess.org/tests/view/5f3fe77a87a5c3c63d8f5332
closes https://github.com/official-stockfish/Stockfish/pull/3048
Bench: 3760677
2020-08-21 03:12:39 -06:00
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assert(d > DEPTH_OFFSET);
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assert(d < 256 + DEPTH_OFFSET);
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2019-05-02 11:36:25 -06:00
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Use 128 bit multiply for TT index
Remove super cluster stuff from TT and just use a 128 bit multiply.
STC https://tests.stockfishchess.org/tests/view/5ee719b3aae8aec816ab7548
LLR: 2.94 (-2.94,2.94) {-1.50,0.50}
Total: 12736 W: 2502 L: 2333 D: 7901
Ptnml(0-2): 191, 1452, 2944, 1559, 222
LTC https://tests.stockfishchess.org/tests/view/5ee732d1aae8aec816ab7556
LLR: 2.93 (-2.94,2.94) {-1.50,0.50}
Total: 27584 W: 3431 L: 3350 D: 20803
Ptnml(0-2): 173, 2500, 8400, 2511, 208
Scheme back to being derived from https://lemire.me/blog/2016/06/27/a-fast-alternative-to-the-modulo-reduction/
Also the default optimized version of the index calculation now uses fewer instructions.
https://godbolt.org/z/Tktxbv
Might benefit from mulx (requires -mbmi2)
closes https://github.com/official-stockfish/Stockfish/pull/2744
bench: 4320954
2020-06-15 00:35:07 -06:00
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key16 = (uint16_t)k;
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Allow TT entries with key16==0 to be fetched
Fix the issue where a TT entry with key16==0 would always be reported
as a miss. Instead, we'll use depth8 to detect whether the TT entry is
occupied. In order to do that, we'll change DEPTH_OFFSET to -7
(depth8==0) to distinguish between an unoccupied entry and the
otherwise lowest possible depth, i.e., DEPTH_NONE (depth8==1).
To prevent a performance regression, we'll reorder the TT entry fields
by the access order of TranspositionTable::probe(). Memory in general
works fastest when accessed in sequential order. We'll also match the
store order in TTEntry::save() with the entry field order, and
re-order the 'if-or' expressions in TTEntry::save() from the cheapest
to the most expensive.
Finally, as we now have a proper TT entry occupancy test, we'll fix a
minor corner case with hashfull reporting. To reproduce:
- Use a big hash
- Either:
a. Start 31 very quick searches (this wraparounds generation to 0); or
b. Force generation of the first search to 0.
- go depth infinite
Before the fix, hashfull would incorrectly report nearly full hash
immediately after the search start, since
TranspositionTable::hashfull() used to consider only the entry
generation and not whether the entry was actually occupied.
STC:
LLR: 2.95 (-2.94,2.94) {-0.25,1.25}
Total: 36848 W: 4091 L: 3898 D: 28859
Ptnml(0-2): 158, 2996, 11972, 3091, 207
https://tests.stockfishchess.org/tests/view/5f3f98d5dc02a01a0c2881f7
LTC:
LLR: 2.95 (-2.94,2.94) {0.25,1.25}
Total: 32280 W: 1828 L: 1653 D: 28799
Ptnml(0-2): 34, 1428, 13051, 1583, 44
https://tests.stockfishchess.org/tests/view/5f3fe77a87a5c3c63d8f5332
closes https://github.com/official-stockfish/Stockfish/pull/3048
Bench: 3760677
2020-08-21 03:12:39 -06:00
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depth8 = (uint8_t)(d - DEPTH_OFFSET);
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genBound8 = (uint8_t)(TT.generation8 | uint8_t(pv) << 2 | b);
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2018-07-03 16:58:16 -06:00
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value16 = (int16_t)v;
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eval16 = (int16_t)ev;
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}
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}
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2008-08-31 23:59:13 -06:00
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2014-02-09 09:31:45 -07:00
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/// TranspositionTable::resize() sets the size of the transposition table,
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2013-02-09 00:17:03 -07:00
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/// measured in megabytes. Transposition table consists of a power of 2 number
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2015-01-17 14:15:15 -07:00
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/// of clusters and each cluster consists of ClusterSize number of TTEntry.
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2008-08-31 23:59:13 -06:00
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2014-07-01 04:13:20 -06:00
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void TranspositionTable::resize(size_t mbSize) {
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2008-08-31 23:59:13 -06:00
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2018-12-08 15:03:42 -07:00
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Threads.main()->wait_for_search_finished();
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Add large page support for NNUE weights and simplify TT mem management
Use TT memory functions to allocate memory for the NNUE weights. This
should provide a small speed-up on systems where large pages are not
automatically used, including Windows and some Linux distributions.
Further, since we now have a wrapper for std::aligned_alloc(), we can
simplify the TT memory management a bit:
- We no longer need to store separate pointers to the hash table and
its underlying memory allocation.
- We also get to merge the Linux-specific and default implementations
of aligned_ttmem_alloc().
Finally, we'll enable the VirtualAlloc code path with large page
support also for Win32.
STC: https://tests.stockfishchess.org/tests/view/5f66595823a84a47b9036fba
LLR: 2.94 (-2.94,2.94) {-0.25,1.25}
Total: 14896 W: 1854 L: 1686 D: 11356
Ptnml(0-2): 65, 1224, 4742, 1312, 105
closes https://github.com/official-stockfish/Stockfish/pull/3081
No functional change.
2020-08-30 10:41:30 -06:00
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aligned_large_pages_free(table);
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2013-04-30 00:08:54 -06:00
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Use 128 bit multiply for TT index
Remove super cluster stuff from TT and just use a 128 bit multiply.
STC https://tests.stockfishchess.org/tests/view/5ee719b3aae8aec816ab7548
LLR: 2.94 (-2.94,2.94) {-1.50,0.50}
Total: 12736 W: 2502 L: 2333 D: 7901
Ptnml(0-2): 191, 1452, 2944, 1559, 222
LTC https://tests.stockfishchess.org/tests/view/5ee732d1aae8aec816ab7556
LLR: 2.93 (-2.94,2.94) {-1.50,0.50}
Total: 27584 W: 3431 L: 3350 D: 20803
Ptnml(0-2): 173, 2500, 8400, 2511, 208
Scheme back to being derived from https://lemire.me/blog/2016/06/27/a-fast-alternative-to-the-modulo-reduction/
Also the default optimized version of the index calculation now uses fewer instructions.
https://godbolt.org/z/Tktxbv
Might benefit from mulx (requires -mbmi2)
closes https://github.com/official-stockfish/Stockfish/pull/2744
bench: 4320954
2020-06-15 00:35:07 -06:00
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clusterCount = mbSize * 1024 * 1024 / sizeof(Cluster);
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Add large page support for NNUE weights and simplify TT mem management
Use TT memory functions to allocate memory for the NNUE weights. This
should provide a small speed-up on systems where large pages are not
automatically used, including Windows and some Linux distributions.
Further, since we now have a wrapper for std::aligned_alloc(), we can
simplify the TT memory management a bit:
- We no longer need to store separate pointers to the hash table and
its underlying memory allocation.
- We also get to merge the Linux-specific and default implementations
of aligned_ttmem_alloc().
Finally, we'll enable the VirtualAlloc code path with large page
support also for Win32.
STC: https://tests.stockfishchess.org/tests/view/5f66595823a84a47b9036fba
LLR: 2.94 (-2.94,2.94) {-0.25,1.25}
Total: 14896 W: 1854 L: 1686 D: 11356
Ptnml(0-2): 65, 1224, 4742, 1312, 105
closes https://github.com/official-stockfish/Stockfish/pull/3081
No functional change.
2020-08-30 10:41:30 -06:00
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table = static_cast<Cluster*>(aligned_large_pages_alloc(clusterCount * sizeof(Cluster)));
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if (!table)
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2008-09-06 04:19:29 -06:00
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{
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2011-04-03 02:19:08 -06:00
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std::cerr << "Failed to allocate " << mbSize
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2011-07-02 06:33:06 -06:00
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<< "MB for transposition table." << std::endl;
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2011-04-03 02:19:08 -06:00
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exit(EXIT_FAILURE);
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2008-08-31 23:59:13 -06:00
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}
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2012-07-07 12:30:27 -06:00
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2018-01-01 02:10:41 -07:00
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clear();
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2008-08-31 23:59:13 -06:00
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}
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2018-07-03 16:48:20 -06:00
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/// TranspositionTable::clear() initializes the entire transposition table to zero,
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// in a multi-threaded way.
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2008-08-31 23:59:13 -06:00
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void TranspositionTable::clear() {
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2008-09-06 04:19:29 -06:00
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2018-05-14 11:52:21 -06:00
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std::vector<std::thread> threads;
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2018-07-03 16:48:20 -06:00
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2018-12-23 08:10:07 -07:00
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for (size_t idx = 0; idx < Options["Threads"]; ++idx)
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2018-05-14 11:52:21 -06:00
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{
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2018-11-22 15:50:03 -07:00
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threads.emplace_back([this, idx]() {
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2018-07-03 16:48:20 -06:00
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// Thread binding gives faster search on systems with a first-touch policy
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2018-09-04 05:36:42 -06:00
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if (Options["Threads"] > 8)
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2018-05-14 11:52:21 -06:00
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WinProcGroup::bindThisThread(idx);
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2018-07-03 16:48:20 -06:00
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// Each thread will zero its part of the hash table
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2020-05-23 05:26:13 -06:00
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const size_t stride = size_t(clusterCount / Options["Threads"]),
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start = size_t(stride * idx),
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2018-07-03 16:48:20 -06:00
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len = idx != Options["Threads"] - 1 ?
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stride : clusterCount - start;
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2018-05-14 11:52:21 -06:00
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std::memset(&table[start], 0, len * sizeof(Cluster));
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2018-11-22 15:50:03 -07:00
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});
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2018-05-14 11:52:21 -06:00
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}
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2008-08-31 23:59:13 -06:00
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2020-05-23 05:26:13 -06:00
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for (std::thread& th : threads)
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2018-05-14 11:52:21 -06:00
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th.join();
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}
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2008-08-31 23:59:13 -06:00
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2020-06-24 14:19:58 -06:00
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2014-12-13 01:27:39 -07:00
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/// TranspositionTable::probe() looks up the current position in the transposition
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/// table. It returns true and a pointer to the TTEntry if the position is found.
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/// Otherwise, it returns false and a pointer to an empty or least valuable TTEntry
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2015-08-15 05:22:54 -06:00
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/// to be replaced later. The replace value of an entry is calculated as its depth
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/// minus 8 times its relative age. TTEntry t1 is considered more valuable than
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/// TTEntry t2 if its replace value is greater than that of t2.
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2008-08-31 23:59:13 -06:00
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2014-12-13 00:16:35 -07:00
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TTEntry* TranspositionTable::probe(const Key key, bool& found) const {
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2009-04-27 06:21:49 -06:00
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2014-10-31 23:48:19 -06:00
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TTEntry* const tte = first_entry(key);
|
Use 128 bit multiply for TT index
Remove super cluster stuff from TT and just use a 128 bit multiply.
STC https://tests.stockfishchess.org/tests/view/5ee719b3aae8aec816ab7548
LLR: 2.94 (-2.94,2.94) {-1.50,0.50}
Total: 12736 W: 2502 L: 2333 D: 7901
Ptnml(0-2): 191, 1452, 2944, 1559, 222
LTC https://tests.stockfishchess.org/tests/view/5ee732d1aae8aec816ab7556
LLR: 2.93 (-2.94,2.94) {-1.50,0.50}
Total: 27584 W: 3431 L: 3350 D: 20803
Ptnml(0-2): 173, 2500, 8400, 2511, 208
Scheme back to being derived from https://lemire.me/blog/2016/06/27/a-fast-alternative-to-the-modulo-reduction/
Also the default optimized version of the index calculation now uses fewer instructions.
https://godbolt.org/z/Tktxbv
Might benefit from mulx (requires -mbmi2)
closes https://github.com/official-stockfish/Stockfish/pull/2744
bench: 4320954
2020-06-15 00:35:07 -06:00
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const uint16_t key16 = (uint16_t)key; // Use the low 16 bits as key inside the cluster
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2008-08-31 23:59:13 -06:00
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2015-01-17 14:15:15 -07:00
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for (int i = 0; i < ClusterSize; ++i)
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Allow TT entries with key16==0 to be fetched
Fix the issue where a TT entry with key16==0 would always be reported
as a miss. Instead, we'll use depth8 to detect whether the TT entry is
occupied. In order to do that, we'll change DEPTH_OFFSET to -7
(depth8==0) to distinguish between an unoccupied entry and the
otherwise lowest possible depth, i.e., DEPTH_NONE (depth8==1).
To prevent a performance regression, we'll reorder the TT entry fields
by the access order of TranspositionTable::probe(). Memory in general
works fastest when accessed in sequential order. We'll also match the
store order in TTEntry::save() with the entry field order, and
re-order the 'if-or' expressions in TTEntry::save() from the cheapest
to the most expensive.
Finally, as we now have a proper TT entry occupancy test, we'll fix a
minor corner case with hashfull reporting. To reproduce:
- Use a big hash
- Either:
a. Start 31 very quick searches (this wraparounds generation to 0); or
b. Force generation of the first search to 0.
- go depth infinite
Before the fix, hashfull would incorrectly report nearly full hash
immediately after the search start, since
TranspositionTable::hashfull() used to consider only the entry
generation and not whether the entry was actually occupied.
STC:
LLR: 2.95 (-2.94,2.94) {-0.25,1.25}
Total: 36848 W: 4091 L: 3898 D: 28859
Ptnml(0-2): 158, 2996, 11972, 3091, 207
https://tests.stockfishchess.org/tests/view/5f3f98d5dc02a01a0c2881f7
LTC:
LLR: 2.95 (-2.94,2.94) {0.25,1.25}
Total: 32280 W: 1828 L: 1653 D: 28799
Ptnml(0-2): 34, 1428, 13051, 1583, 44
https://tests.stockfishchess.org/tests/view/5f3fe77a87a5c3c63d8f5332
closes https://github.com/official-stockfish/Stockfish/pull/3048
Bench: 3760677
2020-08-21 03:12:39 -06:00
|
|
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if (tte[i].key16 == key16 || !tte[i].depth8)
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2009-04-27 06:21:49 -06:00
|
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|
{
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2021-02-11 14:29:28 -07:00
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tte[i].genBound8 = uint8_t(generation8 | (tte[i].genBound8 & (GENERATION_DELTA - 1))); // Refresh
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2014-12-13 00:16:35 -07:00
|
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|
|
Allow TT entries with key16==0 to be fetched
Fix the issue where a TT entry with key16==0 would always be reported
as a miss. Instead, we'll use depth8 to detect whether the TT entry is
occupied. In order to do that, we'll change DEPTH_OFFSET to -7
(depth8==0) to distinguish between an unoccupied entry and the
otherwise lowest possible depth, i.e., DEPTH_NONE (depth8==1).
To prevent a performance regression, we'll reorder the TT entry fields
by the access order of TranspositionTable::probe(). Memory in general
works fastest when accessed in sequential order. We'll also match the
store order in TTEntry::save() with the entry field order, and
re-order the 'if-or' expressions in TTEntry::save() from the cheapest
to the most expensive.
Finally, as we now have a proper TT entry occupancy test, we'll fix a
minor corner case with hashfull reporting. To reproduce:
- Use a big hash
- Either:
a. Start 31 very quick searches (this wraparounds generation to 0); or
b. Force generation of the first search to 0.
- go depth infinite
Before the fix, hashfull would incorrectly report nearly full hash
immediately after the search start, since
TranspositionTable::hashfull() used to consider only the entry
generation and not whether the entry was actually occupied.
STC:
LLR: 2.95 (-2.94,2.94) {-0.25,1.25}
Total: 36848 W: 4091 L: 3898 D: 28859
Ptnml(0-2): 158, 2996, 11972, 3091, 207
https://tests.stockfishchess.org/tests/view/5f3f98d5dc02a01a0c2881f7
LTC:
LLR: 2.95 (-2.94,2.94) {0.25,1.25}
Total: 32280 W: 1828 L: 1653 D: 28799
Ptnml(0-2): 34, 1428, 13051, 1583, 44
https://tests.stockfishchess.org/tests/view/5f3fe77a87a5c3c63d8f5332
closes https://github.com/official-stockfish/Stockfish/pull/3048
Bench: 3760677
2020-08-21 03:12:39 -06:00
|
|
|
return found = (bool)tte[i].depth8, &tte[i];
|
2009-04-27 06:21:49 -06:00
|
|
|
}
|
2010-06-28 01:20:34 -06:00
|
|
|
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2014-12-13 00:16:35 -07:00
|
|
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// Find an entry to be replaced according to the replacement strategy
|
2014-10-31 23:48:19 -06:00
|
|
|
TTEntry* replace = tte;
|
2015-01-17 14:15:15 -07:00
|
|
|
for (int i = 1; i < ClusterSize; ++i)
|
2015-08-20 13:24:37 -06:00
|
|
|
// Due to our packed storage format for generation and its cyclic
|
2021-02-11 14:29:28 -07:00
|
|
|
// nature we add GENERATION_CYCLE (256 is the modulus, plus what
|
|
|
|
// is needed to keep the unrelated lowest n bits from affecting
|
|
|
|
// the result) to calculate the entry age correctly even after
|
|
|
|
// generation8 overflows into the next cycle.
|
|
|
|
if ( replace->depth8 - ((GENERATION_CYCLE + generation8 - replace->genBound8) & GENERATION_MASK)
|
|
|
|
> tte[i].depth8 - ((GENERATION_CYCLE + generation8 - tte[i].genBound8) & GENERATION_MASK))
|
2014-10-31 23:48:19 -06:00
|
|
|
replace = &tte[i];
|
2008-08-31 23:59:13 -06:00
|
|
|
|
2014-12-13 01:27:39 -07:00
|
|
|
return found = false, replace;
|
2008-08-31 23:59:13 -06:00
|
|
|
}
|
2015-01-25 00:57:51 -07:00
|
|
|
|
|
|
|
|
2016-09-23 11:28:34 -06:00
|
|
|
/// TranspositionTable::hashfull() returns an approximation of the hashtable
|
|
|
|
/// occupation during a search. The hash is x permill full, as per UCI protocol.
|
|
|
|
|
|
|
|
int TranspositionTable::hashfull() const {
|
2015-01-25 00:57:51 -07:00
|
|
|
|
|
|
|
int cnt = 0;
|
2020-01-27 10:53:25 -07:00
|
|
|
for (int i = 0; i < 1000; ++i)
|
2018-12-23 08:10:07 -07:00
|
|
|
for (int j = 0; j < ClusterSize; ++j)
|
2021-02-11 14:29:28 -07:00
|
|
|
cnt += table[i].entry[j].depth8 && (table[i].entry[j].genBound8 & GENERATION_MASK) == generation8;
|
2018-12-23 08:10:07 -07:00
|
|
|
|
2020-01-27 10:53:25 -07:00
|
|
|
return cnt / ClusterSize;
|
2015-01-25 00:57:51 -07:00
|
|
|
}
|
2021-02-26 02:02:13 -07:00
|
|
|
|
|
|
|
} // namespace Stockfish
|