Lucas Braesch [Thu, 21 Feb 2013 14:54:06 +0000 (09:54 -0500)]
Prune negative SEE moves also in PV nodes
This patch is actually the sum of two contributions that
have been tested independently:
1) Pruning of negative SEE moves in PV
After 10000 games at 20+0.05
ELO: 5.18 +-7 (95%) LOS: 99.2%
Total: 10000 W: 1952 L: 1803 D: 6245
2) Remove of bestValue > VALUE_MATED_IN_MAX_PLY condition
After 23000 games at 20+0.05
ELO: 1.63 +-4 (95%) LOS: 88.1%
Total: 23000 W: 4232 L: 4124 D: 14644
The whole patch as been re-tested at long TC with positive results:
After 10000 games at 60+0.05
ELO: 4.31 +-7 (95%) LOS: 98.3%
Total: 10000 W: 1765 L: 1641 D: 6594
Marco Costalba [Wed, 20 Feb 2013 11:19:19 +0000 (12:19 +0100)]
Merge Gary's bishop_pin patch
Give a bonus if a bishop can pin a piece or can
give a discovered check through an x-ray attack.
Seems good after 24000 games at 15"+0.05 (single thread):
ELO: 12.30 +- 99%: 5.79 95%: 4.40 LOS: 100.00%
Total: 24000 W: 4931 L: 4082 D: 14987
bench:
4917064
jundery [Tue, 19 Feb 2013 07:54:16 +0000 (00:54 -0700)]
Print leading zeroes in hash keys
And convert to uppercase. Reset the stream to dec too.
[Edit: Also fixed the hash key in Position::pretty()]
Gary Linscott [Tue, 19 Feb 2013 15:31:52 +0000 (10:31 -0500)]
Merge branch 'master' into bishop_pin_clop
Gary Linscott [Tue, 19 Feb 2013 15:31:50 +0000 (10:31 -0500)]
Bring back original bonus
Marco Costalba [Tue, 19 Feb 2013 06:54:14 +0000 (07:54 +0100)]
Update copyright year
No functional change.
Gary Linscott [Sun, 17 Feb 2013 03:36:58 +0000 (22:36 -0500)]
Back to CLOP average values
Marco Costalba [Sat, 16 Feb 2013 11:42:22 +0000 (12:42 +0100)]
Account for gamePly after each move
Rename startPosPly to gamePly and increment/decrement
the variable after each do/undo move. This adds a little
overhead in do_move() but we will need to have the
game ply during the search for the next patches now
under test.
Currently we don't increment gamePly in do_null_move()
becuase it is not needed at the moment. Could change
in the future.
As a nice side effect we can now remove an hack in
startpos_ply_counter().
No functional change.
Marco Costalba [Fri, 15 Feb 2013 15:21:15 +0000 (07:21 -0800)]
Merge Gary's king safety tweak
Still well within error bars, so probably not a big improvement,
but may be worthwhile. I will let the test keep running. The idea
for the tweak came from the TCEC game against Houdini. Stockfish saw
it as a draw, well past when it should have seen problems. King safety
was off, since it was QN and pawns only, but in fact the king was
quite vulnerable.
After 8000 games at 60/1 (Gary's test)
ELO: -0.43 +- 99%: 10.02 95%: 7.62
Wins: 1235 Losses: 1245 Draws: 5520 Total: 8000
PGN of game against houdini. Moves 55-59 it was seeing a draw, and
Houdini was seeing a good sized advantage for black. With the change,
Stockfish now recognizes that moving the king there is a bad idea.
[Event "nTCEC - Stage 1 - Season 1"]
[Site "http://www.tcec-chess.net"]
[Date "2013.02.07"]
[Round "4.2"]
[White "Stockfish 2.31"]
[Black "Houdini 3.0"]
[Result "0-1"]
[Variant "normal"]
1. Nf3 Nf6 2. c4 e6 3. Nc3 Bb4 4. Qc2 O-O 5. a3 Bxc3 6. Qxc3 b6 7. b4 a5 8. Bb2
axb4 9. axb4 Rxa1+ 10. Bxa1 Na6 11. e3 Qe7 12. b5 Nc5 13. Qc2 Bb7 14. Be2 d6
15. O-O Ra8 16. Bb2 h6 17. Ra1 Rxa1+ 18. Bxa1 e5 19. Qa2 Be4 20. Ne1 Bg6
21. Bb2 Kh7 22. f3 Nfd7 23. Bc3 h5 24. Qa1 h4 25. Kf1 Qf6 26. Qa7 Qd8 27. Qa2
e4 28. Qa1 h3 29. g3 exf3 30. Nxf3 Bf5 31. Bd4 g6 32. Kf2 Kg8 33. Qa3 Bg4
34. d3 Qc8 35. Bxc5 bxc5 36. Ke1 Qb7 37. e4 Bxf3 38. Bxf3 Ne5 39. Be2 Qc8
40. Qa6 Qd8 41. Qa5 Kh7 42. Kd1 Kg7 43. Qa7 Kg8 44. Qa5 Kh7 45. Qa7 Kg7 46. Qa5
Qb8 47. Kd2 Kh7 48. Kc2 Kg8 49. Qa6 Qd8 50. Qa5 Qf6 51. Qe1 Kg7 52. Qf1 Qe6
53. Qe1 Qd7 54. Qc1 Qe8 55. Kc3 Qa8 56. Kb3 Kh7 57. Qa3 Qd8 58. Qc1 c6 59. Qc3
Qb6 60. Ka4 Qb7 61. Qd2 Nd7 62. Qc3 Qa7+ 63. Kb3 Kg8 64. Bg4 cxb5 65. cxb5 Nb6
66. Bxh3 Qa4+ 67. Kb2 Qd1 68. Ka3 Qe2 69. Kb3 Qh5 70. Bg2 Qxh2 71. Qf6 Qxg3
72. Bf1 Qe3 73. Kc2 Na4 74. b6 Nxb6 75. Qd8+ Kg7 76. Qxb6 Qf2+ 77. Kc3 Qxf1
78. Qxd6 Qf6+ 79. Qxf6+ Kxf6 80. Kc4 g5 81. Kxc5 Ke5 82. d4+ Kxe4 83. d5 g4
84. d6 g3 85. d7 g2 86. d8=Q g1=Q+ 87. Kb5 Qb1+ 88. Ka4 Qa2+ 89. Kb4 f5
90. Qe8+ Kf4 91. Qg6 Qd5 92. Qg1 Qe4+ 93. Ka5 Qe2 94. Qg8 Kf3 95. Qd5+ Qe4
96. Qd1+ Kg2 97. Qd2+ Kf1 98. Qh2 f4 99. Qh3+ Ke2 100. Qg4+ Kd2 101. Qg5 Kc2
102. Qh4 0-1
bench:
5518286
Marco Costalba [Fri, 15 Feb 2013 07:56:04 +0000 (08:56 +0100)]
Further speed up bitbase generation
Another trick, along the same lines of previous
patch. This time we first check positions with
white side to move that, becuase we start with
pawn on rank 7, are easily classified as wins,
then black ones.
Number of cycles reduced to 15 !
Becuase now it is faster we can remove a lot of
code to detect theoretical draws. We will calculate
them anyhow, although a bit slower, but the speed
up trick more than compensates it.
Verified that generated bitbases match original ones.
No functional change.
Gary Linscott [Fri, 15 Feb 2013 01:29:24 +0000 (20:29 -0500)]
Add new clop tuned value
Gary Linscott [Thu, 14 Feb 2013 02:41:15 +0000 (21:41 -0500)]
Merge branch 'master' into bishop_pin_clop
Gary Linscott [Thu, 14 Feb 2013 02:40:38 +0000 (21:40 -0500)]
Revert "Use CLOP mean value instead of max"
This reverts commit
d0c2faa5fd9ad05f865d2a69b59efab43b2be421.
Marco Costalba [Wed, 13 Feb 2013 11:26:08 +0000 (12:26 +0100)]
Speedup KPK bitbase of 25%
Change the way the index is coded so that
now looping from 0 to IndexMax generates
the pawns from RANK_7 down to RANK2.
Becuase positions with pawns at RANK_7
are easily classified as wins/draws, this
small trick allows to reduce the number
of needed iterations from 30 down to 26!
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Mon, 11 Feb 2013 21:59:37 +0000 (22:59 +0100)]
Simplify bitbase.cpp
Use a std::vector to store positions and
rearrange KPKPosition.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Gary Linscott [Wed, 13 Feb 2013 17:21:16 +0000 (12:21 -0500)]
Use CLOP mean value instead of max
Gary Linscott [Wed, 13 Feb 2013 17:19:54 +0000 (12:19 -0500)]
Merge branch 'simplify_eval' into bishop_pin_clop
Gary Linscott [Wed, 13 Feb 2013 05:12:02 +0000 (00:12 -0500)]
CLOP tuned
Gary Linscott [Tue, 12 Feb 2013 05:10:21 +0000 (00:10 -0500)]
Add clop parameters
Gary Linscott [Mon, 11 Feb 2013 15:26:25 +0000 (10:26 -0500)]
Merge branch 'master' into simplify_eval
Gary Linscott [Mon, 11 Feb 2013 15:26:18 +0000 (10:26 -0500)]
Bishop pins only
Marco Costalba [Sun, 10 Feb 2013 18:10:01 +0000 (19:10 +0100)]
Rename and de-templetize sort()
Rename to insertion_sort so to avoid confusion
with std::sort, also move it to movepicker.cpp
and use the bit slower std::stable_sort in
search.cpp where it is used in not performance
critical paths.
No functional change.
Marco Costalba [Sat, 9 Feb 2013 15:22:47 +0000 (16:22 +0100)]
Further simplify first_entry()
We can encode the ClusterSize directly in the
hashMask, this allows to skip the left shift.
There is no real change, but bench number is now
different because instead of using the lowest order
bits of the key to index the start of the cluster,
now we don't use the last two lsb bits that are
always set to zero (cluster size is 4). So for
instance, if 10 bits are used to index the cluster,
instead of bits [9..0] now we use bits [11..2].
This changes the positions that end up in the same
cluster affecting TT hits and so bench is different.
Also some renaming while there.
bench:
5383795
Marco Costalba [Sat, 9 Feb 2013 09:22:34 +0000 (10:22 +0100)]
Microptimize first_entry() for 32bits
Do a 32bit bitwise 'and' instead of a 64bit
subtract and bitwise 'and'.
This is possible because even in the biggest
hash table case (8GB) the number of entries
is 2^29 so storable in an unsigned int.
No functional change.
Marco Costalba [Sat, 9 Feb 2013 07:17:03 +0000 (08:17 +0100)]
Retire TTCluster and simplify TT
Also some renaming while there.
No functional change.
Marco Costalba [Sat, 9 Feb 2013 05:40:46 +0000 (06:40 +0100)]
Simplify move_to_san()
Nicely simplify disambiguation code.
No functional change.
Gary Linscott [Fri, 8 Feb 2013 13:53:13 +0000 (08:53 -0500)]
Slight tweak to king safety. Bench:
5534531
Marco Costalba [Fri, 8 Feb 2013 10:04:07 +0000 (11:04 +0100)]
Retire slavesPositions
Save the current active position in each Thread
instead of keeping a centralized array in struct
SplitPoint.
This allow to skip a memset() call at each split.
No functional change.
Marco Costalba [Fri, 8 Feb 2013 09:05:04 +0000 (10:05 +0100)]
Add const qualifer to go()
Obsolete renmant of when position was directly
passed to the search instead of being copied
for the main thread as is now.
From Jundery.
No functional change.
Marco Costalba [Fri, 8 Feb 2013 07:49:36 +0000 (08:49 +0100)]
Workaround value-initialization in MSVC
The syntax splitPoints() should force the compiler to
value-initialize the array and because there is no
user defined c'tor it falls back on zero-initialization.
Unfortunatly this is broken in MSVC compilers, because
value initialization for non-POD types is not supported,
so left splitPoints un-initialized and add in split()
initialization of slavesPositions, that is the only
member not already set at split time.
This fixes an assert under MSVC when running with
more than one thread.
Spotted and reported by Jundery.
No functional change.
Gary Linscott [Sun, 3 Feb 2013 20:42:51 +0000 (15:42 -0500)]
Add KBPKP endgame
It is a draw if pawns are on G or B files, weaker pawn is
on rank 7 and bishop can't attack the pawn.
No functional change (because it is very rare and does not appear in bench)
Marco Costalba [Wed, 6 Feb 2013 08:36:13 +0000 (09:36 +0100)]
Change slave_available() API
To return a pointer to the available
thread instead of a bool. This allows
to simplify the core loop in split().
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
jundery [Tue, 5 Feb 2013 17:02:54 +0000 (10:02 -0700)]
Rename posKey stored in the transposition table
[Edit: Slightly extended by me]
No functional change.
jundery [Tue, 5 Feb 2013 17:06:37 +0000 (10:06 -0700)]
Add const qualifer to check_is_dangerous
No functional change.
Marco Costalba [Tue, 5 Feb 2013 05:30:05 +0000 (06:30 +0100)]
Slightly change split() API
This function "returns" two values: bestValue and bestMove
Instead of returning one and passing as pointer the other
be consistent and pass as pointers both.
No functional change.
Marco Costalba [Mon, 4 Feb 2013 21:38:42 +0000 (22:38 +0100)]
Derive ThreadPool from std::vector
Prefer sub-classing to composition in this case.
No functional change.
Marco Costalba [Mon, 4 Feb 2013 21:09:52 +0000 (22:09 +0100)]
Move split() under Thread
Previous renaming patch suggested this reformat:
when a better naming leads to a better code!
No functional change.
Marco Costalba [Mon, 4 Feb 2013 18:48:56 +0000 (19:48 +0100)]
Some renaming in split()
Naming suggested by jundery.
No functional change.
Marco Costalba [Sun, 3 Feb 2013 10:14:21 +0000 (11:14 +0100)]
Be clear about not LMR the ttMove
Currently a ttMove is reduced with ss->reduction = DEPTH_ZERO,
so it is actually not reduced (as it should be), but the
trick works just becuase it happens that ttMove is the first
to be tried and
reduction(depth, 1)
Always returns zero. So explicitly forbid reduction of ttMove
in the LMR condition. This is much clear and self-documented.
No functional change.
Marco Costalba [Sun, 3 Feb 2013 08:52:39 +0000 (09:52 +0100)]
Templetize score_xxx() functions
So to be style-wise aligned with the corresponding
generate() functions.
No functional change.
Marco Costalba [Sun, 3 Feb 2013 08:16:44 +0000 (09:16 +0100)]
Rename prevents_move() to refutes()
Better! From DiscoCheck.
No functional change.
Marco Costalba [Sun, 3 Feb 2013 08:01:55 +0000 (09:01 +0100)]
Correctly score enpassant captures
Surprisingly this rare case was not considered
when scoring a capture.
Also take in account that in the promotion case
we gain a new piece (typically a queen) but we
lose the promoting pawn.
These small issues were present since Glaurung times!
Found while browsing DiscoCheck sources
bench:
5400063
Marco Costalba [Sat, 2 Feb 2013 16:13:33 +0000 (17:13 +0100)]
Unify History and Gains under a single Stats class
Handling of History and Gains is almost the same, with
the exception of the update logic, so unify both
classes under a single Stats struct.
No functional change.
Marco Costalba [Sat, 2 Feb 2013 15:04:41 +0000 (16:04 +0100)]
Retire history.h
And move the contents to movepick.cpp, where they are
mostly used.
Idea from DiscoCheck.
No functional change (bench
5379503)
Gary Linscott [Sat, 2 Feb 2013 15:19:59 +0000 (10:19 -0500)]
Simplify eval take 2. Bench
5097444
Marco Costalba [Sat, 2 Feb 2013 05:44:20 +0000 (06:44 +0100)]
Restore "fail-low of reduced" and close regression
This reverts "Threat Extensions" and is the last of
this revert series.
In single-thread tests we should now be on par with 2.3.1
Marco Costalba [Sat, 2 Feb 2013 05:43:11 +0000 (06:43 +0100)]
Revert "Simplify Evaluation"
This reverts commit
496c7497cb81de4383
Marco Costalba [Mon, 28 Jan 2013 16:24:01 +0000 (17:24 +0100)]
Revert "Extend full 3 fold detection to PvNodes"
Marco Costalba [Sun, 27 Jan 2013 17:48:27 +0000 (18:48 +0100)]
Rewrite do_castle_move()
And handle the castle directly in do/undo_move().
This allow to greatly simplify the code.
Here the beast is the nasty Chess960 that is
really tricky to get it right because could be
that 'from' and 'to' squares are the same or
that king's 'to' square is rook's 'from' square.
Anyhow should work: verified on all Chess960
starting positions.
No functional and no speed change also in Chess960.
Marco Costalba [Sun, 27 Jan 2013 10:45:01 +0000 (11:45 +0100)]
Rewrite do_null_move()
Use a more traditional approach, along the same lines
of do_move().
It is true that we copy more in do_null_move(), but we
save the work in undo_null_move(). Speed test shows the
new code to be even a bit faster.
No functional change.
Marco Costalba [Sun, 27 Jan 2013 09:56:03 +0000 (10:56 +0100)]
Get rid of some locals in do_castle_move()
Rewrite the logic to get rid of kBefore and rBefore.
No functional change.
Marco Costalba [Sun, 27 Jan 2013 09:15:59 +0000 (10:15 +0100)]
Don't prefetch if not needed
Prefetch access to hash tables only in case we
have changed pawn or material hash keys.
No functional change.
Marco Costalba [Sat, 26 Jan 2013 21:07:28 +0000 (22:07 +0100)]
Retire generate_king_moves()
We have only one call place so inline its content.
BTW, function is already declared as FORCE_INLINE.
Also some small refactoring while there.
No functional change.
Gary Linscott [Sat, 26 Jan 2013 20:35:00 +0000 (15:35 -0500)]
Bring back just bishop pins
Marco Costalba [Sat, 26 Jan 2013 13:23:37 +0000 (14:23 +0100)]
Clarify slavesMask usage
When a thread is allocated a bit is set in slavesMask.
This bit corresponds to the thread's index field that,
because it happens to be the position in the threads
array, eventually it is equal to the loop index 'i'.
But instead of relying on this 'coincidence', explicitly
use the 'idx' field so to clarify slavesMask usage.
Backported from c++11 branch.
No functional change.
Marco Costalba [Mon, 21 Jan 2013 22:14:10 +0000 (23:14 +0100)]
Revert "Further push singular extension"
This reverts commit
4c91dbc28e8bb6265f8
Seems a regression on extended test by both Gary and me.
Marco Costalba [Fri, 25 Jan 2013 20:01:24 +0000 (21:01 +0100)]
Merge branch 'simplify_eval' of https://github.com/glinscott/Stockfish
Test results are looking good after 12500 games.
ELO: 6.55 +- 99%: 8.02 95%: 6.09
LOS: 99.99%
Wins: 1968 Losses: 1732 Draws: 8813
Also, here are the noise.py results, which seem to have stabilized:
Games: 12526 , result: [1969, 1734, 8823]
Estimated ELO: 6.
94963842777
Noise as function of number of games:
['81.89', '565.26', '110.87', '104.39', '38.22', '49.98', '18.56', '16.76',
'11.02', '8.90', '17.36', '9.84', '10.81', '5.13', '6.22', '3.32', '5.83',
'7.21', '15.27', '1.63', '4.04', '9.51', '0.54', '0.75', '1.06', '2.93',
'4.59', '6.85', '13.62', '9.87', '14.74', '20.46', '22.18', '24.33', '31.02',
'34.99', '35.22', '33.22', '32.46', '37.02', '29.10', '36.34', '42.11', '39.33',
'26.16', '28.25', '35.42', '31.04', '29.26', '23.91', '22.52', '23.49', '20.00',
'24.39', '17.22', '16.50', '10.69', '9.15', '9.57', '4.77', '6.67', '3.87', '2.57',
'2.84', '2.60', '3.32', '2.08', '2.93', '4.47', '4.41', '4.83', '4.86', '6.40',
'5.98', '6.10', '6.83', '5.83', '6.22', '5.71', '8.52', '9.25', '5.98', '7.52',
'7.76', '8.76', '8.55', '8.64', '7.19', '5.83', '4.59', '4.77', '4.26', '4.98',
'5.29', '5.41', '4.92', '5.59']
bench:
5229106
Gary Linscott [Thu, 24 Jan 2013 13:54:13 +0000 (08:54 -0500)]
Simplify evaluation
Marco Costalba [Mon, 21 Jan 2013 16:22:31 +0000 (17:22 +0100)]
Small reformat of split()
No functional chhange.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sun, 20 Jan 2013 16:24:06 +0000 (17:24 +0100)]
Fix an idiotic icc warning
Intel Compiler has 'invented' this pearl:
warning #1476: field uses tail padding of a base class
Just becuase we have subclassed MainThread and added
the field 'bool thinking'.
Pure nosense. Silence the warning.
No functional change.
Marco Costalba [Sun, 20 Jan 2013 10:54:30 +0000 (11:54 +0100)]
Futher renaming in thread.cpp
No functional change.
Marco Costalba [Wed, 16 Jan 2013 08:28:41 +0000 (09:28 +0100)]
Big renaming in thread stuff
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Wed, 16 Jan 2013 08:26:10 +0000 (09:26 +0100)]
Fix race while exiting
Fix again TimerThread::idle_loop() to prevent a
theoretical race with 'exit' flag in ~Thread().
Indeed in Thread d'tor we raise 'exit' and then
call notify() that is lock protected, so we
have to check again for 'exit' before going to
sleep in idle_loop().
Also same change in Thread::idle_loop() where we
now check for 'exit' before to go to sleep.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Lucas Braesch [Tue, 1 Jan 2013 03:51:35 +0000 (11:51 +0800)]
Remove Threat Extension
Great code simplification: - instead do not futility
prune threat refutations. allows_move() is therefore removed.
4000 games at 50,000 nodes/move:
1085-989-1926 [51.2%] LOS=98.3%
4000 games in 10"+0.1"
756-751-2493 [50.1%] LOS=55.1%
EDIT: I have retested the patch of Lucas in a slightly different form
(without pruning in PvNode) and test mre or less confirms that
60 lines of code are totally unuseful:
After 6195 games at 15"+0.05"
1333 - 1325 - 3537 ELO 0
bench
5140990
Marco Costalba [Mon, 14 Jan 2013 18:32:30 +0000 (19:32 +0100)]
Fix a bug in timer loop
Silly logic bug introduced in
dda7de17e74d7e8
Timer thread, when msec = 0, instead of going
to sleep, calls check_time() in an endless loop.
Spotted and reported by snino64 due to abnormally
high CPU usage.
No functional change.
Marco Costalba [Sun, 13 Jan 2013 23:32:30 +0000 (00:32 +0100)]
Polymorphic Thread hierarchy
Subclass MainThread and TimerThread and declare
idle_loop() virtual. This allow us to cleanly
remove a good bunch of hacks, relying on C++
polymorphism to do the job.
No functional change.
Marco Costalba [Sun, 13 Jan 2013 17:38:44 +0000 (18:38 +0100)]
Don't use do_sleep flag
Rename it is_finished and use it only in main
thread to signal search is finished. This allows
us to simplify the complex SMP logic.
Ultra tricky patch: deep test is required under
wide conditions like pondering on and option
"Use Sleeping Threads" set to false.
No functional change.
Marco Costalba [Sun, 13 Jan 2013 22:51:15 +0000 (23:51 +0100)]
Re-add the hack
This reverts commit
869c9244101
I misunderstood here. Actually it can happen that
thread is created but still not entered idle_loop
and at the same time start_searching() is called.
Becuase 'do_sleep' is set start_searching() will
set it to false and start the search, but when,
at last, the thread enters idle_loop(), resets
the flag and goes to sleep: not what we want.
Revert the hack waiting for a better solution
in the next patches.
No functional change.
Marco Costalba [Sun, 13 Jan 2013 17:22:33 +0000 (18:22 +0100)]
Retire set_timer()
Also assure in Thread::timer_loop() that when
timer interval is 0 (timer is disabled) we
never call check_time()
No functional change.
Marco Costalba [Sun, 13 Jan 2013 16:04:39 +0000 (17:04 +0100)]
Retire obsolete race hack
This hack was introduced in
d282cf6964d493
to workaround a race with start_searching(),
but these days is no more needed.
No functional change.
Marco Costalba [Sun, 13 Jan 2013 14:50:57 +0000 (15:50 +0100)]
Retire Threads wake_up() and sleep()
These functions are used in just one place.
And generalize wait_for_stop()
No functional change.
Marco Costalba [Sun, 13 Jan 2013 14:35:38 +0000 (15:35 +0100)]
Rename wake_up() to notify_one()
To align to C++ std::thread conventions.
No functional change.
Marco Costalba [Sun, 13 Jan 2013 13:36:27 +0000 (14:36 +0100)]
Unify 'ponderhit' handling
Finally we can now merge the 'ponderhit' case with
'stop' and 'quit'.
The patches have been done step by step to help debugging
becuase this is really tricky code.
No functional change.
Marco Costalba [Sun, 13 Jan 2013 13:28:22 +0000 (14:28 +0100)]
Small change to "ponderhit" handling
Reset Limits.ponder only if search continue, but if
we are going to stop the search there is no need
(and is also confusing) to clear the 'ponder' flag.
This mimics the behaviour upon rceiving 'stop' when
pondering.
No functional change.
Marco Costalba [Sun, 13 Jan 2013 13:15:19 +0000 (14:15 +0100)]
Simplify and rename wait_for_stop_or_ponderhit()
Setting stopOnPonderhit is now done by the caller.
No functional change.
Marco Costalba [Sun, 13 Jan 2013 11:34:31 +0000 (12:34 +0100)]
Simplify a condition in search()
And rearrange best value update in case of SpNode.
No functional change.
Marco Costalba [Sat, 12 Jan 2013 12:19:06 +0000 (13:19 +0100)]
Clarify SAN disambiguation in case of a pinned piece
In SAN notation when two pieces of the same type can
move to a given destination square, a disambiguation
additional info (like starting file) shall be added
to the SAN move.
If one of the two pieces is pinned, the corresponding
move _could_ be illegal and in this case disambiguation
is not needed. But to be pinned alone it is not enough
to deduce that the move is illegal, for instance in this
position:
R3rk2/2r6/8/8/8/8/8/K7 b - - 0 1
The move Rc8 is ambiguous although the rook in e8 is pinned
and the correct SAN notation should be Rcc8.
No functional change.
Marco Costalba [Sun, 6 Jan 2013 11:49:01 +0000 (12:49 +0100)]
Async 'stop' command
Don't wait for the search to finish after a 'stop'
command, but keep processing the GUI input if any.
Also explicitly wake up the main thread (that could be
sleeping) after a 'stop' or 'quit' command and do not
rely on wait_for_search_finished() doing it for us.
This patch cleans up the code and functions's definitions,
but it is risky and needs a good test under different
conditions to be sure it does not introduces hungs up.
No functional change.
Marco Costalba [Sun, 6 Jan 2013 21:55:35 +0000 (22:55 +0100)]
Revert so called "fromNull patch"
Revert patch
c581b7ea3627482
Seems a regression after testing from Gary:
ELO: 7.24 +- 99%: 17.03 95%: 12.93
LOS: 97.86%
Wins: 439 Losses: 381 Draws: 1962
And mine:
After 5410 games at 15"+0.05
Wins: 936 Losses: 1141 Draws: 3333 ELO -13
Moreover we know that there is a regression in the range
of patches which include the fromNull patch.
Probably this is not the only regression since 2.3.1 and
perhaps the idea under fromNull is good, but at the moment,
while in deep regression hunting, better to be on the safe
side and revert it entirely.
My guess on why this is a regression is that using the
negated evaluation of previous ply in case of null search
fails to take in account the king safety asymmetry between
the two colors. This is of course just a guess.
bench
5503830
Marco Costalba [Sat, 5 Jan 2013 14:24:18 +0000 (15:24 +0100)]
Have fun with union in book.cpp
Fancy way to use an union to map polyglot
zobrist keys in one go.
Also some renaming while there.
No functional change.
Marco Costalba [Fri, 4 Jan 2013 15:49:24 +0000 (16:49 +0100)]
Retire 'Cowardice' and 'Aggressiveness' UCI options
They are not self-describing and create a lot of user
requests about them.
Given that the values are already well tuned there
is no need to expose them as UCI options.
No functional change.
Marco Costalba [Fri, 4 Jan 2013 15:29:13 +0000 (16:29 +0100)]
Retire 'mate in x' hack
Sometimes is faster, but not always and on very long mates
produces strange scores probably due to truncation of PV
artifacts.
So simply perform normal search also in case of UCI 'mate x'
command, with the only difference that when a mate in x is
found search returns immediately.
No functional change.
Marco Costalba [Fri, 4 Jan 2013 13:52:21 +0000 (14:52 +0100)]
Don't exit if unable to find bench file
Now that we can call 'bench' command also from
interactive terminal it makes no more sense to
exit the application if the user types a wrong
file name.
No functional change.
Marco Costalba [Fri, 4 Jan 2013 13:10:35 +0000 (14:10 +0100)]
Teach file_to_char() about upper/lower case
This allows to further simplify Position::fen()
No functional change.
Marco Costalba [Fri, 4 Jan 2013 11:32:13 +0000 (12:32 +0100)]
Reformat FEN construction
Simplify and shrink code.
No functional change.
Marco Costalba [Mon, 31 Dec 2012 15:28:40 +0000 (16:28 +0100)]
Remove some obsolete asserts on TT values
Now that insert_pv_in_tt() stores VALUE_NONE in
TT's position evaluation those 2 asserts are
obselete.
No functional change.
Marco Costalba [Mon, 31 Dec 2012 10:57:49 +0000 (11:57 +0100)]
Allow to pass a 'seed' to RKISS
This somewhat simplifies the code.
Suggested by Lucas Braesch.
No functional change.
Marco Costalba [Mon, 31 Dec 2012 10:26:12 +0000 (11:26 +0100)]
Micro-optimization in evaluate_space()
Since &-ing with SpaceMask restricts the set to the home
half of the board, it is possible to use just one popcount
instead of 2 by shifting "safe" to the other half of the
board. This gives a small speedup especially on systems
where hardware popcount is not available.
Patch kindly sent by Richard Vida.
No functional change.
Marco Costalba [Sun, 30 Dec 2012 14:48:37 +0000 (15:48 +0100)]
Add 'mate' limit to 'bench' command
It is now possible to run SF on a 'mate in x' testsuite.
For instance in case of a file with fen strings of
positions with mate in 10 we can now 'bench' on it:
stockfish bench 128 1 10 mate_in_10.epd mate
No functional change.
Marco Costalba [Sun, 30 Dec 2012 10:40:20 +0000 (11:40 +0100)]
Handle UCI command "mate in x moves"
Following a user request I added the handling of UCI:
go mate x
Currently we just return from a PV node if x moves have been
done. Probably not the best approach. I have looked at Fruit/Toga
sources and there is even simpler: engine falls back on a fixed
depth search.
No functional change.
Marco Costalba [Thu, 27 Dec 2012 11:13:31 +0000 (12:13 +0100)]
Revert evaluation cache
And return on using TT as backing store for position
evaluations.
Tests (even on single thread) show eval cache was a regression.
In multi thread result should be even worst because eval cache
is a per-thread struct, while TT is shared.
After 4957 games at 15"+0.05 (single thread)
eval cache vs master 969 - 1093 - 2895 -9 ELO
So previous reported result of +18 ELO was probably due to an
issue in the testing framework (a bug in cutechess-cli) that
has been fixed in the meanwhile.
bench:
5386711
Marco Costalba [Thu, 27 Dec 2012 10:08:20 +0000 (11:08 +0100)]
Add list of legal moves to Position::pretty()
Along the same lines of previous patch now we add
the list of the legal moves in the given position.
No functional change.
Marco Costalba [Wed, 26 Dec 2012 17:22:56 +0000 (18:22 +0100)]
Add checkers info to Position::pretty()
In case current position is under check, list the
squares of the checker(s) pieces.
This should satisfy a specific user request.
No functional change.
Marco Costalba [Wed, 26 Dec 2012 11:27:09 +0000 (12:27 +0100)]
Remove two obsolete asserts in prevents_move
Now that this function is called also to calculate
move's extensions the asserts are no more valid.
No functional change.
Marco Costalba [Wed, 26 Dec 2012 11:15:55 +0000 (12:15 +0100)]
Rename yields_to_threat and prevents_threat
Follow Lucas suggestions and better name these
two functions.
No functional change.
Marco Costalba [Mon, 24 Dec 2012 08:07:17 +0000 (09:07 +0100)]
Introduce Null Threat extension
In case of null search at low depths returns a fail low
due to a threat then, rather than return beta-1 (to cause
a re-search at full depth in the parent node), we set a flag
threatExtension = true (false by default) that will cause
moves that prevent the threat to be extended of one ply
in the following search.
Idea and patch is by Lucas Braesch.
Lucas also did the tests:
1500 games in 5"+0.05":
SF_threatExtension vs SF_20121222: 366 - 331 - 803 [51.2%] LOS=90.8%
3000 games in 10"+0.1":
SF_threatExtension vs SF_20121222: 610 - 559 - 1831 [50.8%] LOS=93.2%
Tests confirmed by Gary after 10570 games,
ELO: 2.79 +- 99%: 8.72 95%: 6.63
LOS: 94.08%
Wins: 1523 Losses: 1438 Draws: 7607
And finally by me at 15"+0.05, single thread, 3824 games
threatExtension vs master 768 - 692 - 2364 +7 ELO
bench
4918443
Marco Costalba [Tue, 25 Dec 2012 17:48:41 +0000 (18:48 +0100)]
Fix a couple of extra spaces
No functional change.
Marco Costalba [Tue, 25 Dec 2012 16:59:35 +0000 (17:59 +0100)]
Retire Position::in_check()
It is redundant with Position::checkers()
No functional change.
Marco Costalba [Tue, 25 Dec 2012 10:40:28 +0000 (11:40 +0100)]
Retire Position::move_is_legal()
Use the new contains() method of struct MoveList
No functional change.
Marco Costalba [Tue, 25 Dec 2012 10:22:55 +0000 (11:22 +0100)]
Small tweak in is_pseudo_legal()
This is difficult code becuase a bug here could lead
to very subtle crashes in case of SMP games where we
have TT move corruption due to concurrent access.
Anyhow I have fully verified te code throwing at it
random moves. It shoudl work.
No functional change.