Marco Costalba [Thu, 6 May 2010 12:22:53 +0000 (14:22 +0200)]
Rename futilityMargin in kingDanger in EvalInfo
This is what actually is.
A standard naming convention suggests to name a variable
with someting resembling _what_ the variable is and not
_how_ the variable is used. This normally results
in easier to read code.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sun, 2 May 2010 11:02:41 +0000 (12:02 +0100)]
Do not return from idle_loop() with lock held
Master thread returns from idle_loop() when sp->cpus == 0,
but cpus is decremented by slave threads under sp->lock,
so it could happen that we return in split(), where we release
the split point, with sp->lock still held.
This patch guarantees that sp->lock is released when returning
to split().
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Thu, 29 Apr 2010 17:21:48 +0000 (18:21 +0100)]
Refresh TT entry after a cut-off to avoid aging
Re-save the same TT entry if value is usable and allow
us to cut-off, it means that entry is valuable and
we want to keep it fresh updating the 'generation'
parameter up to the current value.
Patch suggested by J. Wesley Cleveland and better
clarified by Miguel A. Ballicora.
After 999 games at 1+0 64MB hash size
Mod vs Orig +167 =677 -155 +4 ELO
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sun, 25 Apr 2010 09:31:48 +0000 (10:31 +0100)]
Do not call exit_threads() in Application d'tor
Because exit_threads() references the global object TM, we
need to call the function when still inside main(), otherwise,
due to undefined global object initialization and destruction
we could end up with referencing an already destroyed object.
Actually this should not happen because Application singleton
is initialized _only_ after all the other globals due to how
Application::initialize() is defined, but this is very tricky
C++ and not easy to follow, even for me ;-)
Also rearranged a bit main() code flow.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sun, 25 Apr 2010 07:39:24 +0000 (08:39 +0100)]
Small passed pawns evaluation cleanup
Moved evaluation of unstoppable pawns out of
evauation of passed pawns because event frequency is
much lower. Added evaluate_unstoppable_pawns() that
is called very seldom and contains all the unstoppable
pawn logic.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Mon, 19 Apr 2010 07:06:34 +0000 (09:06 +0200)]
Introduce PawnsQtyTable[] to refine pawn's drawish calculation
Also fix dimension of UnpairedPawnsTable[] to accomodate the
case in which we have 8 unpaired pawns, i.e. only one side has
pawns, the other side has no pawns.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sat, 10 Apr 2010 09:32:17 +0000 (10:32 +0100)]
Avoid TT cutoffs at root of null zugzwang verification
This patch fixes an issue with zugzwang well explained by Tord:
"Assume that a zugzwang position occurs at iteration N,
at a search depth d, with d < 6*OnePly. The null move search
fails high, and no verification search is done, because the
depth is too small. The position gets stored in the transposition
table with a good score and a depth of d.
Now, consider what happens when the same position occurs at iteration
N+1, this time with a depth of d+OnePly (i.e. one ply deeper than at
the previous iteration). Once again, the null move search fails
high. The point is that the verification search will also fail high,
because of an instant transposition table cutoff caused by the value
stored in the TT during the previous iteration."
With this patch we simply do not allow TT cutoffs at the root node
of a null move verification search if the TT value was found by a
null search.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sat, 3 Apr 2010 07:54:21 +0000 (08:54 +0100)]
Store score in TT when null search fails high
Use full depth, not reduced one. This allows
to avoid to do a null search when in the same
position and at the same or bigger depth the
null search failed high.
A very small increase, if any.
After 963 games at 1+0
Mod vs Orig: +158 =657 -147 +4 ELO
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Tord Romstad [Tue, 30 Mar 2010 13:15:01 +0000 (15:15 +0200)]
Remove several unnecessary UCI options: All king safety options
except "Aggressiveness" and "Cowardice", and "UCI_ShowCurrLine".
No functional change compared to the previous version with the
default settings.
Marco Costalba [Sat, 20 Mar 2010 10:59:22 +0000 (11:59 +0100)]
Remove castleRightsMask[] hack
Array castleRightsMask[] is not static because it can
be different for different positions, so let it be
a Position member data. This allows to remove tricky
hacks to take in account that although it was defined
static it could change.
Theoretically now copying a position is a bit slower because
we need to copy also an array of 64 integers, but because in
split() we don't copy the position anymore, but just keep the
pointer, the added burden is not mesurable even in MP case.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Wed, 17 Mar 2010 17:09:37 +0000 (18:09 +0100)]
Fix POPCNT detection gcc compile error
Also don't use __cpuid() intrinsic for Intel under
Linux because gives wrong results when detecting HT,
use the gcc version instead. Finally clean up the code.
Error was due to changed __cpuid() signature for
gcc compiler.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Tue, 9 Mar 2010 14:46:20 +0000 (15:46 +0100)]
Reduce increase progression of aspiration window
Currently, in case of fail high/low we research with
a window increased by 2*AspirationDelta at first
attempt, this patch instead makes the research be
done with an increase of just AspirationDelta size,
in case of a consecutive fail we will widen to
2*AspirationDelta and so on.
After Joona's test:
Orig - Mod: 850 - 890
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sun, 7 Mar 2010 08:02:34 +0000 (10:02 +0200)]
Use separated research counters in root_search()
One for failing highs and one for failing lows, this
should reduce average window size in case of positions
that fail first high and then low (or the contrary).
After ~2000 games on Joona's quad we have:
Mod - Orig: 1012- 975 (+6 elo)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sat, 6 Mar 2010 10:43:31 +0000 (11:43 +0100)]
Sort again root moves after a fail low
Currently we use original sorting after a fail low to
research at wider window. This patch instead sorts the
moves according to the last available move's scores.
Strangely no functional change, but should be.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sun, 28 Feb 2010 10:53:29 +0000 (11:53 +0100)]
We don't need lpThreadId parameter in CreateThread()
Under Windows we use CreateThread() to setup threads and
we pass a pointer to a variable that receives the thread
identifier, but this parameter is optional and we don't
use it, so remove it.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba [Sat, 27 Feb 2010 11:01:07 +0000 (12:01 +0100)]
Remove an incorrect assert in wake_sleeping_threads()
Currently there is no guarantee that threads are sleeping
when calling wake_sleeping_threads() because put_threads_to_sleep()
returns without waiting for threads to actually sleep.
Assert can be easily triggered calling put_threads_to_sleep() and
wake_sleeping_threads() in a tight loop.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
projects / stockfish / log