Commit Graph
43 Commits
Author SHA1 Message Date
VoyagerOneandJoona Kiiski 05cf45f2d1 Razor Simplification
Remove code that restrict using tt-moves for razoring.

STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 67442 W: 12039 L: 11997 D: 43406

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 38541 W: 5044 L: 4947 D: 28550

Bench: 5667216

Closes #1002
2017-02-18 22:50:37 -08:00
VoyagerOneandJoona Kiiski 83fb4547f6 search(): Move nullValue variable into local scope
No functional change

Closes #1003
2017-02-14 21:22:58 -08:00
VoyagerOneandJoona Kiiski 0553b46829 Simplify Queen Mobility
STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 85997 W: 15550 L: 15540 D: 54907

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 25333 W: 3370 L: 3256 D: 18707

Bench: 6459194

Closes #991
2017-02-05 15:40:30 -08:00
VoyagerOneandMarco Costalba fa24cc25a4 Simplify TT penalty stat (#980)
STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 20251 W: 3692 L: 3570 D: 12989

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 16432 W: 2155 L: 2029 D: 12248

Bench: 5941174
2017-01-29 08:54:58 +01:00
VoyagerOneandMarco Costalba 5254a6040c Penalty for a quiet ttMove that fails low
Also the penalty/bonus function is misleading, we
should simply change it to stat_bonus(depth) for
bonus and -stat_bonus(depth+ ONE_PLY) for extra
penalty.

STC:
LLR: 2.96 (-2.94,2.94) [0.00,5.00]
Total: 11656 W: 2183 L: 2008 D: 7465

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 11152 W: 1531 L: 1377 D: 8244

Bench: 6101931
2017-01-28 09:32:07 +01:00
VoyagerOneandMarco Costalba 8c61bbda54 Another simplification for SEE pruning
STC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 29310 W: 5225 L: 5118 D: 18967

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 128454 W: 16424 L: 16442 D: 95588

Bench: 4556848
2016-12-17 08:37:58 +01:00
VoyagerOneandMarco Costalba b915fdc889 Reduction Simplification
Simplify reduction formula by removing a parameter.

STC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 35798 W: 6368 L: 6272 D: 23158

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 125375 W: 15827 L: 15839 D: 93709

Bench: 4735038
2016-11-05 08:17:42 +01:00
VoyagerOneandMarco Costalba d4abf54247 Top CPU Contributors
Give some well needed credit...

No functional change.
2016-11-05 08:12:22 +01:00
VoyagerOneandMarco Costalba e77f38c431 History Stat Comparison
Adjust LMR by comparing history stats
with opponent (prior ply).

STC:
LLR: 2.96 (-2.94,2.94) [0.00,5.00]
Total: 27754 W: 5066 L: 4824 D: 17864

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 216596 W: 28157 L: 27343 D: 161096

Bench: 5437729
2016-10-25 06:44:19 +02:00
VoyagerOneandMarco Costalba e27d3bb884 Use explicit logic for pruning
Also a speedup since we don't need to recalculate SEE
for extensions...as it already determined to be positive.

Results for 12 tests for each version:

        Base      Test      Diff
Mean    2132395   2191002   -58607
StDev   128058    85917     134239
p-value: 0.669
speedup: 0.027

Non functional change.
2016-10-18 08:53:51 +02:00
VoyagerOneandMarco Costalba ab26c61971 Allow inCheck pruning
This is a bit tricky because we don't want
to prune the only legal evasions, even if
with negative SEE. So add an assert to avoid
this subtle bug to slip in later.

STC:
LLR: 2.96 (-2.94,2.94) [0.00,4.00]
Total: 14140 W: 2625 L: 2421 D: 9094

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,4.00]
Total: 11558 W: 1555 L: 1379 D: 8624

bench: 5256717
2016-10-03 16:18:53 +02:00
VoyagerOneandMarco Costalba 95ad2b51b7 Tweak SEE margin in pruning conditions
Use 35 * depth^2 to calculate see_margin.

STC:
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 22636 W: 4212 L: 3990 D: 14434

LTC:
LLR: 2.96 (-2.94,2.94) [0.00,5.00]
Total: 47241 W: 6314 L: 6041 D: 34886

The Movepick SEE is now dead code, retire it.

Bench: 5341477
2016-09-14 15:38:38 +02:00
VoyagerOneandMarco Costalba 2731bbaf6b Remove condition on killers in history pruning
Now allows main killer to be history prune.

STC:
LLR: 2.94 (-2.94,2.94) [-3.00,1.00]
Total: 15852 W: 2910 L: 2781 D: 10161

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 56428 W: 7610 L: 7537 D: 41281

Bench: 8032058
2016-08-30 09:09:55 +02:00
VoyagerOneandMarco Costalba 0b4f6e562b Refutation penalty on captures
Apply refutation penalty for prior PV quiet move on captures

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 8208 W: 1153 L: 1008 D: 6047
http://tests.stockfishchess.org/tests/view/57bc5a9f0ebc59030fbe47b5

Only LTC because a very similar patch already passed STC + LTC

bench: 7038730
2016-08-24 08:26:32 +02:00
VoyagerOneandMarco Costalba 5596492f6e Simplify IID
STC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 30468 W: 5687 L: 5582 D: 19199
http://tests.stockfishchess.org/tests/view/57b1ddd80ebc591c761f63e2

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 87406 W: 11756 L: 11725 D: 63925
http://tests.stockfishchess.org/tests/view/57b212590ebc591c761f63f9

bench: 6554900
2016-08-19 08:59:18 +02:00
VoyagerOneandMarco Costalba 8493c8c6b8 Do LMR on captures
STC:
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 5361 W: 1086 L: 936 D: 3339
http://tests.stockfishchess.org/tests/view/57b31b0f0ebc591c761f643d

LTC:
LLR: 2.96 (-2.94,2.94) [0.00,5.00]
Total: 54694 W: 7591 L: 7287 D: 39816
http://tests.stockfishchess.org/tests/view/57b3442b0ebc591c761f6450

bench: 6881120
2016-08-19 08:50:14 +02:00
VoyagerOneandMarco Costalba 7396c08b79 Use predicted depth for history pruning
STC: (Yellow)
LLR: -2.96 (-2.94,2.94) [0.00,4.00]
Total: 69115 W: 12880 L: 12797 D: 43438

LTC:
LLR: 2.96 (-2.94,2.94) [0.00,4.00]
Total: 124163 W: 16923 L: 16442 D: 90798

Note: Note based off past experiments / patches... history pruning
is quite TC sensitive. I believe the reason for this TC dependency
is that the CMH/FMH is a very large table that takes time to fill
up with. In addition having more time for will increase the accuracy
of the stats' value.

Bench: 7351698
2016-08-15 14:45:40 +02:00
VoyagerOneandMarco Costalba b3525fa9ea Use Color-From-To history stats to help sort moves
STC:
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 33502 W: 6498 L: 6223 D: 20781
http://tests.stockfishchess.org/tests/view/578abb940ebc5972faa169e2

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 50782 W: 7124 L: 6832 D: 36826
http://tests.stockfishchess.org/tests/view/578b8e5d0ebc5972faa169fd

LTC: (Sanity test against latest master)
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 32759 W: 4600 L: 4370 D: 23789
http://tests.stockfishchess.org/tests/view/5798b7d30ebc591c761f5b72

bench: 6985912

P.S. Thanks @mstembera for rewriting my code to make it smp compatible. A BIG thank you!
2016-08-02 09:17:14 +02:00
VoyagerOneandMarco Costalba 85924db496 Futility tweak
Use a different margin for pruning child nodes.

STC:
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 16692 W: 3251 L: 3051 D: 10390
http://tests.stockfishchess.org/tests/view/579b95d10ebc591c761f5c03

LTC:
LLR: 2.97 (-2.94,2.94) [0.00,5.00]
Total: 24140 W: 3501 L: 3297 D: 17342
http://tests.stockfishchess.org/tests/view/579bb15d0ebc591c761f5c0b

Bench: 7927017
2016-08-01 21:47:42 +02:00
VoyagerOneandMarco Costalba c94145b65c Comment out a redundant condition
Take advantage that VALUE_NONE = 32002 to remove
the condition.

Commented out and not removed becuase it is tricky
to rely on the hidden value of VALUE_NONE and code
can break in case we change VALUE_NONE in the future.

No functional change.
2016-06-24 08:26:39 +02:00
VoyagerOneandMarco Costalba 1c0c4db677 Simplify Check Extension
STC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 32704 W: 6146 L: 6045 D: 20513

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 146622 W: 19967 L: 20017 D: 106638

Bench: 8245662
2016-06-18 08:32:25 +02:00
VoyagerOneandMarco Costalba 7d2a79f037 Stat Formula Tweak
bonus = d * d + 2 * d - 2

STC:
LLR: 2.94 (-2.94,2.94) [0.00,4.00]
Total: 99444 W: 18274 L: 17778 D: 63392

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,4.00]
Total: 89757 W: 12285 L: 11896 D: 65576

bench: 8276130
2016-06-10 07:27:47 +02:00
VoyagerOneandMarco Costalba 7c5d724724 Tweak check extension condition
There are two concepts with this patch:

Limit check extensions by using move count.
The idea is to limit search explosion.

Always extend check if the first move gives check.
The idea is to save expensive SEE calls, since the vast
majority of first move will have SEE value >= 0, also
first move may still be strong even if the SEE is negative.

STC:
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 16503 W: 3068 L: 2873 D: 10562

LTC:
LLR: 2.97 (-2.94,2.94) [0.00,5.00]
Total: 37202 W: 5261 L: 5014 D: 26927

bench: 8543366
2016-06-10 07:15:56 +02:00
VoyagerOneandMarco Costalba 5f096e9bef Simplify Futility Pruning
Don't update bestValue when futility pruning.

STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 21933 W: 4031 L: 3912 D: 13990

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 46225 W: 6115 L: 6028 D: 34082

Bench: 8450534
2016-06-03 19:58:42 +02:00
VoyagerOneandMarco Costalba 5486911e01 Simplify History LMR Formula
STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 41713 W: 7589 L: 7504 D: 26620

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 41353 W: 5484 L: 5391 D: 30478

Bench: 8946983
2016-05-05 08:53:50 +02:00
VoyagerOneandJoona Kiiski e082112cfe Use FMHs to assist with LMR formula.
STC:
LLR: 2.99 (-2.94,2.94) [0.00,5.00]
Total: 52232 W: 9654 L: 9304 D: 33274

LTC:
LLR: 2.97 (-2.94,2.94) [0.00,5.00]
Total: 115988 W: 15550 L: 15049 D: 85389

Bench: 7890808

Resolves #651
2016-04-24 01:00:58 +01:00
VoyagerOneandJoona Kiiski 60590577f2 A small simplification in movepick.h
No functional change

Resolves #597
2016-03-14 20:54:49 -07:00
VoyagerOneandJoona Kiiski 45a309d92e Simplify Reduction Formula
Formula now only contains one coefficient. Making it much easier to tune.

STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 187443 W: 34858 L: 35028 D: 117557

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 88329 W: 11982 L: 11953 D: 64394

Bench: 7521394

Resolves #591
2016-02-28 13:31:25 +00:00
VoyagerOneandJoona Kiiski bfe9044ad9 History Stat Formula Simplification
STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 67476 W: 12561 L: 12521 D: 42394

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 111923 W: 15147 L: 15149 D: 81627

Bench: 8430465

Resolves #588
2016-02-21 20:12:33 +00:00
VoyagerOneandJoona Kiiski 744ed85a4d Fix futility pruning bug
PredictedDepth can be negative, causing the futility_margin to be negative.
It will be very difficult to tweak moveCount pruning and reduction formula, as they are tuned to prevent this behavior.

No functional change

Resolves #587
2016-02-14 19:48:46 +00:00
VoyagerOneandJoona Kiiski ed72a1e9ba Remove killer move conditions from LMR
STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 8459 W: 1619 L: 1477 D: 5363

LTC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 32239 W: 4404 L: 4299 D: 23536

Bench: 7597031

Resolves #534
2015-12-20 20:41:17 +00:00
VoyagerOneandJoona Kiiski 07e0741dfb History Pruning: Don't prune the main killer move.
Also increased pruned depth to 4.

STC:
LLR: 2.96 (-2.94,2.94) [0.00,5.00]
Total: 23380 W: 4581 L: 4350 D: 14449

LTC:
LLR: 2.96 (-2.94,2.94) [0.00,5.00]
Total: 28934 W: 4329 L: 4105 D: 20500

Bench: 8369743

Resolves #498
2015-11-15 20:40:09 -08:00
VoyagerOneandJoona Kiiski aa242d2f84 New History Bonus Formula
bonus = d^2 + d - 1

Bench: 8639247

Resolves #484
2015-10-31 18:17:00 +00:00
VoyagerOneandMarco Costalba 4eca981e55 History pruning
Prune moves with negative History
and CMH scores at low depth.

STC:
LLR: 2.96 (-2.94,2.94) [0.00,5.00]
Total: 24182 W: 4672 L: 4439 D: 15071

LTC:
LLR: 2.97 (-2.94,2.94) [0.00,5.00]
Total: 12579 W: 1959 L: 1792 D: 8828

bench: 8907701
2015-10-24 09:30:31 +02:00
VoyagerOneandGary Linscott 8fd34d7763 Combination of two ideas:
Apply bonus for the prior CMH that caused a fail low.

Balance Stats: CMH and History bonuses are updated differently.
This eliminates the "fudge" factor weight when scoring moves. Also
eliminated discontinuity in the gravity history stat formula. (i.e. stat
scores will no longer inverse when depth exceeds 22)

STC:
LLR: 2.96 (-2.94,2.94) [0.00,5.00]
Total: 21802 W: 4107 L: 3887 D: 13808

LTC:
LLR: 2.96 (-2.94,2.94) [0.00,5.00]
Total: 46036 W: 7046 L: 6756 D: 32234

Bench: 7677367
2015-10-12 14:00:54 -07:00
VoyagerOneandGary Linscott a2410227cc PV refutation penalty
Extra penalty for PV move in previous ply when it gets refuted.

STC:
LLR: 4.49 (-2.94,2.94) [-1.50,4.50]
Total: 41094 W: 7889 L: 7620 D: 25585

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,6.00]
Total: 12304 W: 1967 L: 1811 D: 8526

Bench: 8373608

Resolves #386
2015-07-30 00:51:49 +08:00
VoyagerOneandJoona Kiiski 1d977aa79e LMR Simplification: Remove countermove condition
Removed countermove condition for decreasing reduction.

LTC:
LLR: 3.01 (-2.94,2.94) [-3.00,1.00]
Total: 32410 W: 5092 L: 4986 D: 22332

STC:
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 24450 W: 4632 L: 4517 D: 15301

Bench: 6943812

Resolves #378
2015-07-15 20:21:14 +01:00
VoyagerOneandJoona Kiiski aa0dc16b75 CMH Fix: Exclude captures for TT move refutation penalty
This will make sure we store only quiet moves for TT Penalty.

STC:
LLR: 2.96 (-2.94,2.94) [-1.50,4.50]
Total: 34748 W: 6617 L: 6420 D: 21711

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 19975 W: 3259 L: 3137 D: 13579

Bench: 8063826

Resolves #373
2015-07-04 14:22:41 +01:00
VoyagerOneandJoona Kiiski 7e9f776fca LMR Tweak: Decrease reduction if cmh>0 && history>0.
STC:
LLR: 2.96 (-2.94,2.94) [-1.50,4.50]
Total: 9627 W: 1879 L: 1748 D: 6000

LTC:
LLR: 2.97 (-2.94,2.94) [0.00,6.00]
Total: 21543 W: 3433 L: 3234 D: 14876

Bench: 8646407

Resolves #370 #371
2015-06-27 09:45:59 +01:00
VoyagerOneandJoona Kiiski b7063ef65b Change extra ply LMR condition to: cmh <= 0 && hist < 0
Extra ply LMR condition is now cmh <= 0 && h < 0
Instead of cmh + h < 0

STC:
LLR: 2.96 (-2.94,2.94) [-1.50,4.50]
Total: 55210 W: 10812 L: 10557 D: 33841

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,4.00]
Total: 13212 W: 2239 L: 2045 D: 8928

Bench: 8420865

Resolves #339
2015-04-26 20:12:25 +01:00
VoyagerOneandJoona Kiiski 20e92895af Removed extra condition (history < 0) in LMR to help sync up with move ordering.
LMR condition is now cmh+history<0
Instead of history<0 OR cmh+history<0

STC:
LLR: 2.96 (-2.94,2.94) [-3.00, 1.00]
Total: 26446 W: 5092 L: 4980 D: 16374

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00, 1.00]
Total: 14129 W: 2340 L: 2209 D: 9580

Bench: 7815183

Resolves #331
2015-04-12 20:05:59 +01:00
VoyagerOneandJoona Kiiski ac8e6ff000 Use CounterMoveHistory when calculating LMR for cut nodes
If the sum of CounterMoveHistory heuristic and History heuristic is below zero,
then reduce an extra ply in cut nodes

LTC:
LLR: 2.96 (-2.94,2.94) [0.00,6.00]
Total: 6479 W: 1099 L: 967 D: 4413

Bench: 7773299

Resolves #315
2015-03-28 21:15:49 +00:00
VoyagerOneandJoona Kiiski e51965aa57 Introduce a new counter move history penalty
Extra penalty for TT move in previous ply when it gets refuted

STC:

LLR: 2.94 (-2.94,2.94) [-1.50,4.50]
Total: 31303 W: 6216 L: 6025 D: 19062

LTC:

LLR: 2.97 (-2.94,2.94) [0.00,6.00]
Total: 6950 W: 1189 L: 1054 D: 4707

Bench: 8191926

Resolves #309
2015-03-24 23:04:08 +00:00