Commit Graph
100 Commits
Author SHA1 Message Date
Marco Costalba d156e7a20b Use a boolean instead as thread's state
Now that we have just two mutually exclusive thread's states
we can repleace them by a simple boolean.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-10 12:26:52 +01:00
Marco Costalba c386ce0023 Remove Thread::WORKISWAITING
Set the state directly to Thread::SEARCHING

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-10 12:05:33 +01:00
Marco Costalba b69d9ee3f7 Don't need pthread_detach() after pthread_join()
Spotted by Joona and verified with Valgrind.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-10 08:17:15 +01:00
Marco Costalba 7d5b8fcf77 Change start_routine argument
Directly pass the thread pointer.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-09 14:19:44 +01:00
Marco Costalba bc6a6e04a0 Retire Rml full PV search at depth == 1
Now that Rml ordering is based on normal MovePicker logic,
apart for the ttMove that is given, we can avoid to score
all the root moves at depth 1. We only need it for easy move
detection logic, but in this case we just need to score the
first two best moves and not all the Rml set.

No regression after 6400 games
Mod vs Orig 1052 1012 4336 ELO +2 (+- 4.9)

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-09 09:58:10 +01:00
Marco Costalba e5ffe9959c Retire ThreadsManager::init_hash_tables()
Allocation of pawn and material hash tables should
be strictly bounded to the change of the number of
activeThreads, so move the code inside set_size().

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-08 23:08:34 +01:00
Marco Costalba 86b95f2105 Retire Thread::TERMINATED
Use proper way to detect for thread terimnation instead of
our homegrown flag.

It adds more code than it removes and adds also platform specific
code, neverthless I think is the way to go becuase Thread::TERMINATED
flag is intrinsecly racy given that when we raise it thread is still
_not_ terminated nor it can be, and also we don't want to reinvent
the (broken) wheel of thread termination detection when there is
already available the proper one.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-08 22:10:01 +01:00
Marco Costalba 1e92df6b20 Retire Thread::INITIALIZING
Was used to prevent issues when creating multiple threads
on Windows, but now it seems we can remove it safely.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-08 14:12:02 +01:00
Marco Costalba ba85c59d96 Move idle_loop() under Thread
This greatly removes clutter from the difficult idle_loop() function

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-08 13:23:03 +01:00
Marco Costalba dafd5b5864 Tidy up comments in thread.cpp
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-08 11:49:58 +01:00
Marco Costalba eabba1119f Retire broken SendSearchedNodes
Now that we can split at root it happens that SendSearchedNodes
works only once at the end of the iteration, but this is useless
becuase speed info is sent anyhow toghter with the pv line.

So retire for now, waiting to find something SMP compatible.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-08 10:08:41 +01:00
Marco Costalba 06e0d48794 Sync search() and qsearch() alpha update
Change qsearch() to reflect alpha update logic
of search().

To be consistent changed also moves loop condition and
futility pruning condition.

No regression after 5072 games at TC 10"+0.1

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-08 07:46:01 +01:00
Marco Costalba 4a71c86270 Retire Thread::BOOKED
Start a slave as soon as is allocated.

No functional change with faked split.

Regression tested the full split() series and after
2000 games no regression and no crash.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-08 07:45:24 +01:00
Marco Costalba 68583f4d48 Fix obey the "maxThreadsPerSplitPoint" setting
Spotted by Joona.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-07 15:15:19 +01:00
Marco Costalba 5b35c149e8 Do not modify alpha in split()
When calling split or we immediately return because unable to
find available slaves, or we start searching on _all_ the moves
of the node or until a cut-off occurs, so that when returning
from split we immediately leave the moves loop.

Because of this we don't need to change alpha inside split() and
we can use a signature similar to search() so to better clarify
that split() is actually a search on the remaining node's moves.

No functional change with faked split.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-07 15:10:41 +01:00
Marco Costalba 9a542d9698 Initialize a new split point out of lock
Allocate and initialize a new split point
out of lock becuase modified data is local to
master thread only.

Also better document why we need a lock at
the end of split().

No functional change with faked split.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-07 14:37:14 +01:00
Marco Costalba cd27ed9a74 Update comment on why we call root search with ss+1
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-07 10:36:14 +01:00
Marco Costalba b9f8cb7837 Fix an assert when stopping the search
When StopRequest is raised we cannot immediately exit the
move loop but first we need to update bestValue so to avoid
assert:

assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-07 10:36:13 +01:00
Marco Costalba 30b3edf328 Simplify MovePickerExt<>
Now that we don't special case the root moves anymore
we don't need to pass NodeType anymore as template parameter,
a simple bool to detect a SpNode will be enough.

Spotted by Joona.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-05 07:23:54 +01:00
Marco Costalba 7902d6089e Fix silly bug in uci loop
After issuing "go"-command, at the end of the search
SF shows: "Unknown command: ...".

Spotted by Joona.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-05 07:15:45 +01:00
Marco Costalba b6b0878da8 Fix a (silly) warning under icc compiler
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-04 10:10:03 +01:00
Marco Costalba 3a76163aba Use std::lexicographical_compare() in UCI options
Instead of our home grown function to perform a case
insensitive compare on option names as required by UCI
protocol.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-03 15:00:23 +01:00
Marco Costalba 1e7c6fc761 Consistently set ttMove to Rml.pv[0] in root node
No functional change, but reduce risks of subtle aliasing bugs.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-02 22:28:03 +01:00
Marco Costalba c50ad85c3c Fix an off-by-one error in UCI print loop
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-02 21:47:31 +01:00
Marco Costalba bb6a6e159a Rename ok_to_use_TT() in can_return_tt()
Seems more appropiate. From Lucas Braesch's DoubleCheck.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-02 18:49:06 +01:00
Marco Costalba 1036cadcec Send PV only for updated lines
It seems FritzGUI already remembers the old lines, so
we just need to update PV info only for the new lines.

Also introduced prevScore field in RootMove to avoid
a bulk copy of Rml.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-02 18:00:47 +01:00
Marco Costalba c71ae794df Sort PV moves always in two steps
This should fix following issue:

Suppose the search with MultiPVIteration == 0 returns an exact score

move = Nxf4, score = 100

Now search with MultiPVIteration == 1 and get two scores

move = Qg8, score = 150
move = Ra1, score = 180

If we now reorder all the moves in one step we end up with

pv[0] = Ra1, pv[1] = Qg8

Instead reordering as the current patch we end up in:

pv[0] = Ra1, pv[1] = Nxf4

preserving the first searched move.

No functional change in single PV.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-02 18:00:47 +01:00
Marco Costalba 409930e98c Small cleanup of previous patches
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-08-02 18:00:22 +01:00
Marco Costalba 2e2a4b4ea3 Fix pretty_pv() output in Chess960
And move it to search.cpp

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-26 12:39:15 +01:00
Marco Costalba ff1ecb5d6c Tidy up benchmark.cpp
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-24 08:53:36 +01:00
Marco Costalba dab1cd8af9 Rename execute_uci_command() to uci_loop()
As a side effect now root position can be directly
allocated on the stack and doesn't need to be defined
static anymore.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-24 08:12:07 +01:00
Marco Costalba 5b0c6b9bc0 Unhide the istringstream behind UCIParser
It is misnamed because it is not a parser, perhaps a
tokenizer, anyhow better call it for what it is, an
input string stream.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-24 07:39:07 +01:00
Marco Costalba fc290dc30b Fix startpos_ply_counter() regression
Return the correct number of played plies at the end
of the setup moves. Currently it always returns 0 when
starting from start position, like in real games.

We fix this adding st->pliesFromNull that starts from 0
and is incremented after each setup move and is never
reset in the setup phase but only once search is started.

It is an hack because startpos_ply_counter() will return
different values during the search and is correct only
at the beginning of the search.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-24 06:59:14 +01:00
Marco Costalba 5f7eb20090 Use a circular buffer to keep track of setup states
This fixes a regression on real games due to the fact that
we have some mismatches:

    history[st->gamePly - i] != stp->key

when st->gamePly - i == 0,this is due to a nasty bug I have
introduced when using std::vector<> as StateInfo backup. The
point is that StateInfo keeps inside a pointer to the previous
StateInfo in a kind of linked list. But when std::vector<> is
resized reallocates a larger chunk of memory and moves the
data there so these pointers became stale.

This patch fixes the issue.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-24 06:15:40 +01:00
Marco Costalba 03ad183384 Don't update gamePly after each move
We just need startup value to calculate available
thinking time. So remove from state.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-24 06:15:39 +01:00
Marco Costalba 527a2ec541 Use std::vector<Move> to store UCI search moves
Avoid the ugly and anyhow incorrect hard limit on the
maximum number of moves and allow to handle an arbitrary
number of moves to search.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-24 06:15:38 +01:00
Marco Costalba 3185c36a65 Use st->gamePly to store fullMoves
This allow to retire do_setup_move() and also to simplify
draw detection logic becuase now we always have:

Min(st->rule50, st->gamePly) = st->rule50

This was already true when starting from starting position,
but now is true even when starting from a FEN string because
now we take in account fullmove number in counting gamePly so
that it is always.

st->rule50 <= st->gamePly

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-24 06:15:36 +01:00
Marco Costalba 3d8140a541 Retire history[]
Use key saved in state instead.

No functional change (in real games) and no speed regression.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-24 06:15:35 +01:00
Marco Costalba a1f9bf19d9 Revert previous patches due to bug
We have a bug (possibly because of returning draw from
root move list), it is possible to see when looking at
games with a GUI, we can see rarely but consistently the
score return as #0 for many depths until it comes back to
normal values.

Revert patches until it is not fixed.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-20 03:34:39 +01:00
Marco Costalba 07e0dd27fb Small touches in set_option()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-17 12:55:26 +01:00
Marco Costalba b8eb699db7 Validate input UCI moves
Running following command:

  position startpos moves e1e8

Makes SF to assert in debug mode in do_move() but to accept
bad input and continue in release mode where probably it is
going to crash little later.

So validate input before to feed do_move().

Suggestion by Yakovlev Vadim.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-17 10:22:55 +01:00
Marco Costalba ad1f28bc1c Remove some useless include
Spotted by Rein Halbersma.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-16 22:59:14 +01:00
Marco Costalba 67686b7684 Don't need to assert for pos.is_ok() when position is constant
It's only necessary to do the checking at the end of every non-const
member (including the constructors and from_fen()) of class Position.
Once the post-condition of every modifier guarantees the class invariant,
we don't need to verify sanity of the position as preconditions for outside
callers such as movegen, search etc. For non-class types such as Move and
Square we still need to assert of course.

Suggested by Rein Halbersma.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-16 10:53:34 +01:00
Marco Costalba 69f4954df1 Change hidden checkers API
After previous patch is no more needed to pass
the color, becuase it is always the side to move.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-16 10:12:46 +01:00
Marco Costalba 4894231ff7 Simplified discovered check connected_moves()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-16 09:50:35 +01:00
Marco Costalba 36bb57a47e Simplify and micro-optimize hidden_checkers()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-16 08:53:21 +01:00
Marco Costalba a042449f5d No need to declare default Position c'tor
Pointed out by Rein Halbersma.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-15 21:53:47 +01:00
Marco Costalba f5e434c2d9 Fix a warning under MSVC
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-15 12:20:31 +01:00
Marco Costalba 37d551fb39 Fix parametrized direction in pawns generation
It worked by accident because we always called both directions,
but definition was wrong.

Functional change due to different generation order, but
perft numbers are the correct ones.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-15 12:13:55 +01:00
Marco Costalba 9c8c0de538 Cleanup handling of Delta enums
Ispired by Rein's code.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-15 12:13:48 +01:00
Marco Costalba fbdabe2975 Use std library to sort moves
Functional change due to the fact that now pick_best() is
stable, but should be no change in strenght.

Example code and ideas by Rein Halbersma.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-14 12:43:13 +01:00
Marco Costalba 0cfb30e5be Fix icc's "unreachable code" warning
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-11 11:17:50 +01:00
Marco Costalba c081a81daf Teach to_fen() about Halfmove and Fullmove number
And also fix the last '/' at the end of the piece placement field.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-03 12:08:02 +01:00
Marco Costalba 155bed18f5 Use MoveList also in Position::move_is_pl_slow()
And rename it in Position::move_is_legal()

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-03 11:00:28 +01:00
Marco Costalba 95d9687d95 Retire move_is_short_castle() and move_is_long_castle()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-03 10:27:15 +01:00
Marco Costalba ff41b8df76 Restore startpos_ply_counter() instead of full_moves()
And pass correct currentPly to TimeManager::init().

This restores old behaviour, in particular now black has
a different timing than white becuase is no more:

currentPly = 2 * fullMoveNumber;

but becomes

2 * (fullMoves - 1) + int(sideToMove == BLACK)

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-03 06:54:46 +01:00
Marco Costalba 53ccba8457 Introduce and use struct MoveList
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-02 14:04:33 +01:00
Marco Costalba 7ac6e3b850 Remove MSVC debug window hack in bench
Interference with profile-build under mingw

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-02 11:52:22 +01:00
Marco Costalba d15217b953 Rearrange structs to avoid internal padding
Found with gcc -Wpadded gcc option.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-02 11:01:12 +01:00
Marco Costalba bc54a44010 Revert PHQ-2
No clear advantage again standard, possibly we will
retest before to release.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-07-02 09:47:06 +01:00
Marco Costalba 3f806df0ca Small touches to do/undo_castle_move()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-30 20:04:46 +01:00
Marco Costalba f3799aa750 Better document generate_castle_moves()
No functional change also in Chess960

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-30 19:58:44 +01:00
Marco Costalba 30ca6935a5 Small tweaks to search()
No functional change also in faked split mode

To be sure verified in real games with 4 threads TC 2"+0.1
After 11125 games 2497 - 2469 - 6159 ELO +0 (+- 4.4)

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-30 06:54:09 +01:00
Marco Costalba f25582d4b8 Remove duplicated enum Phase definition
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-29 17:54:12 +01:00
Marco Costalba fb2fdb21d3 Retire find_checkers()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-28 18:01:51 +01:00
Marco Costalba 31a0d2200c Retire square_is_weak()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-28 17:22:33 +01:00
Marco Costalba e0a00c4996 Retire one piece_list() overload
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-28 17:11:03 +01:00
Marco Costalba e5077dc11e Rename pieces_of_color() in pieces()
To be uniform with other overloads.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-28 17:10:44 +01:00
Marco Costalba 01a191936e Retire redundant square_is_occupied()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-28 17:10:27 +01:00
Marco Costalba 8094b2add8 Change Position::pst() signature
To be more clear what is the underlying table.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-28 17:10:18 +01:00
Marco Costalba ffb638995d Fix Shredder-FEN regression in from_fen()
Fix also an incredible 3% speed regression by an almost
never called function. I guess this is due to mingw very low
quality standard libraries implementation.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-28 17:10:05 +01:00
Marco Costalba c2a4856f9e Greatly simplify castling rights handling
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-27 19:26:30 +01:00
Marco Costalba c9b24c3358 Assume input FEN string is correct in from_fen()
And also tolerate a 0 value for full move number.

Revert BUG_41 patch, now we set initial King file only
if a castling is possible, so we don't need the fix
anymore in case of correct FEN.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-27 12:08:12 +01:00
Marco Costalba 9305983018 Fix a bug in Position::is_ok()
If we cannot castle castleRightsMask[] could be not valid,
for instance when king initial file is FILE_A as queen rook.

In this case castleRightsMask[] at initialQRFile is different
from the expected (ALL_CASTLES ^ WHITE_OOO).

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-26 11:44:12 +01:00
Marco Costalba ae2f5f25cd Rename type_of_piece() and color_of_piece()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-26 10:52:42 +01:00
Marco Costalba 923b14afaa Retire Position::color_of_piece_on()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-26 10:37:13 +01:00
Marco Costalba a9782b94e6 Retire Position::type_of_piece_on()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-26 10:28:54 +01:00
Marco Costalba 351ef5c85b Retire seeValues[] and move PieceValue[] out of Position
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-26 10:19:37 +01:00
Marco Costalba be2925b3c5 Restore user weights to 100
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-24 10:31:03 +01:00
Marco Costalba ace27831ee PHQ settings for King and Mobility
See:
http://talkchess.com/forum/viewtopic.php?t=39327

After 8130 games on QUAD at 20"+0.1
1342 - 1359 - 5429 ELO +0 (+- 4.4)

Tried also version with just king settings changed:
After 5932 games 962 - 1052 - 3918 ELO -5 (+- 5.2)

And with just mobility settings changed:
After 4114 games 618 - 619  - 2877 ELO +0 (+- 5.9)

Frank has tested only 1200 games, but at longer TC and
against many engines, so because PHQ results are not worst
than other combination and not worst than original let's
commit his version.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-24 09:47:30 +01:00
Marco Costalba 6a1707889c Fix move_is_capture() to detect capture promotions
We miss to account as a capture a promotion capture !

Incredible bug in this critical function that is here
since a long time (b50921fd5c of 21/10/2009 !!)

This patch fixes the bug and readds the faster
move_is_capture_or_promotion() that slightly increases
overall speed.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-23 12:09:31 +01:00
Marco Costalba 1c42d15340 Rewrite how uci info is sent to GUI
It is now much more modular than before and also we
always send the seldepth when we send the depth, this
avoids to make seldepth disappearing from GUI at the
start of a new iteration.

Print also fails high/low pv lines at high enough
search depths.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-22 17:32:22 +01:00
Marco Costalba fe26967ea0 Simplify sliding_attacks()
Easy, almost trivial simplification, I don't understand
how I missed this before !!

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-21 19:01:00 +01:00
Marco Costalba e7413417ce Retire ksq from CheckInfo
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-21 12:13:26 +01:00
Marco Costalba 018022b866 Use CheckInfo to store pinned bitboard
This trivial change gives an impressive 2,5% speedup !!!!

Also retire one unused move_gives_check() overload.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-20 12:09:11 +01:00
Marco Costalba 7ea38e980b Omit mate distance pruning at root
Restore original behaviour, before root unification and
remove a now useless ugly hack for alpha in multi-pv case.

No functional change

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-18 17:11:09 +01:00
Marco Costalba 8173d92dd2 Use an array index instead of an iterator in root list
It is not correct to use an iterator stick on a vector that
is sorted becuase iterator is invalidated in general case.

It happens to work by accident because iterators are implemented
as pointers and so they behave in the same (correct) way then
using array indices, but the latters are the correct thing to use.

Also better document the code.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-18 08:03:59 +01:00
Marco Costalba 808a4fe817 Remove useless bestValue = alpha assignement
It is a fossil from the root_search() era, no more
needed today.

Spotted by Onno

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-15 12:49:59 +01:00
Marco Costalba 72760c05c6 Try only recaptures in qsearch if depth is very low
This avoids search explosion in qsearch for some
patological cases like:

r1n1n1b1/1P1P1P1P/1N1N1N2/2RnQrRq/2pKp3/3BNQbQ/k7/4Bq2 w - - 0 1

After 9078 games 20"+0.1 QUAD:
Mod vs Orig 1413 - 1319 - 6346 ELO +3 (+- 4)

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-15 12:17:49 +01:00
Marco Costalba 15683034a7 Speed up kpk initialization
The trick is to classify more position at first cycle,
so to reduce following work. Speed up is of about 50% !

Also some cleanup while there.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-15 12:11:35 +01:00
Marco Costalba 4c9d570e43 Use Carry-Rippler trick to speed up magics
Nice trick discovered on:

http://chessprogramming.wikispaces.com/Traversing+Subsets+of+a+Set

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-15 02:15:41 +01:00
Marco Costalba fc519ca74a Retire init_piece_square_tables()
Merge in init_zobrist() and rename the latter.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-13 17:28:09 +01:00
Marco Costalba a24c0a736c Increase LMR limit by one ply
Seems there is no regression so prefer to prune less.

After 8278 games
Mod vs Orig 1246 - 1265 - 5767 +0 ELO (+- 4.2)

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-12 21:14:07 +01:00
Marco Costalba b3a0b389d2 Better self-document init_zobrist()
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-12 11:50:19 +01:00
Marco Costalba 47959c56fd Fix initialization of BSFTable[]
We should start from i = 0, it works by accident because
static storage BSFTable[] is init to zero by default.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-12 11:37:02 +01:00
Marco Costalba aee75ae105 Don't update_gains() in qsearch
Is almost unuseful becuase captures are skipped.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-12 07:09:30 +01:00
Marco Costalba 4b8a7f2793 Fix score_captures() for the case of capture promotions
In case we have more than one promotion move, prefer
the one that captures the biggest piece.

Almost no functional change, anyhow I don't expect any
ELO change, it is just the correct thing to do.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-11 22:12:13 +01:00
Marco Costalba 89ec224cb9 Retire some unused functions
No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-11 15:56:12 +01:00
Marco Costalba b21a5e2f06 Micro-optimize castling handling in do_move()
And better self-document the code.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-11 15:31:39 +01:00
Marco Costalba 735cac5d53 Retire PieceLetters struct
Use a much simpler std::string instead.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
2011-06-10 17:12:10 +01:00