Creating an History object requires clearing the History tables,
although fast is an useless job in san.cpp where History is used
just as a dummy argument for MovePicker c'tor.
So use a file scoped constant instead of creating a new History()
object each time MovePicker c'tor is called as in move_ambiguity()
This optimizes pretty_pv() through the following calling chain:
pretty_pv() -> line_to_san() -> move_to_san() -> move_ambiguity()
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This also allow us to better track what is already
optimized and what still needs optimization.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
King evaluation is special in any case and as an added
benefit we can use the HasPopCnt optimization also for king.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This is an old patch, was part of a series, but is
good also alone as a cleanup.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Also move NodesSincePoll away from the same cache line
of other heavy read accessed only variables.
Fortunatly we don't have anymore write access contention,
but still read access contention in some cases.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
They are always true anyway and are heavy used file scope
variables where there could be SMP contention. Although read only.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This reduces contention and reduce history trashing
effect especially at high search depths.
No functional change for single CPU case.
After 999 games at 1+0 on Dual Core Intel we have
Mod vs Orig +233 =526 -240 -2 ELO
We need to test at longer time controls and possibly with
a QUAD where we could foreseen an improvment.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This is a first step for future patches and in
any case seems a nice thing to do.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
In Position we store a pointer to a StateInfo record
kept outside of the Position object.
When copying a position we copy also that pointer so
after the copy we have two Position objects pointing
to the same StateInfo record. This can be dangerous
so fix by copying also the StateInfo record inside
the new Position object and let the new st pointer
point to it. This completely detach the copied
Position from the original one.
Also rename setStartState() as saveState() and clean up
the API to state more clearly what the function does.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Do not penalize if in our adavncing pawn's path there are
non-pawns enemy pieces. Especially if they can be attacked
by us.
Patch is mine, but original idea and also fixing of a first, wrong,
version of the patch is from Eelco de Groot.
Tests with Joona framework seems to confirm patch is good
Results for patch 'disabled' based on 5776 games: Win percentage:
41.309 (+- 0.526) [+- 1.053]
Results for patch 'enabled' based on 6400 games: Win percentage:
42.422 (+- 0.500) [+- 1.000]
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Tests on Joona luxury iCore7 QUAD show that speed increase
against standrd 64bit routine is between 3% and 4%.
So it seems a good thing to have. Also the user feedback at
startup regarding the compile and the hardware detection can
be an useful debug tool.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
In MovePicker consider killer moves as a separate
phase from non-capture picking.
Note that this change guarantees that killer1 is always
tried before killer2. Until now, because scoring difference
of the two moves was just 1 point, if psqt tables of killer1
gave a lower value then killer2, the latter was tried as first.
After 999 games at 1+0 we have
Mod vs Orig: +245 =527 -227 +6 ELO
Not a lot but patch is anyhow something worth to have.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
It shows almost no improvment and adds a good
bunch of complexity.
So remove for now. No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
We don't need different names between a function and a
template. Compiler will know when use one or the other.
This let use restore original count_1s_xx() names instead of
sw_count_1s_xxx so to simplify a bit the code.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
With this patch at the applications startup a line is printed
with info about use of optimized 64 bit routines and hardware
POPCNT.
Also allow the possibility to disable POPCNT support during
PGO compiles to exercise the fallback software only path.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Runtime detect POPCNT instruction support and
use it.
Also if POPCNT is not supported we don't add _any_ overhead so
that we don't lose any speed in standard case.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Unfortunatly, due to Chess960 compatibility we cannot
extend also to castling where the destinations squares
are not guaranteed to be empty.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Avoid a clear_bit() + set_bit() sequence but update bitboards
with only one xor instructions.
This is faster and simplifies the code.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This gives more weight to newer entries.
After 999 games at 1'+ 0" we have:
Mod vs Orig +233/-208/=558 51.25% +9 ELO
Confirmed by another session of 437 games:
Mod vs Orig +109/-92/=236 51.95% +14 ELO
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Use the plain array lookup in the only place where it
is used. This remove an unecessary indirection and better
clarifies what code does.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This is the same change we have already done in search.cpp,
this time for evaluation.cpp
If a variable will be populated reading an UCI option
then do not hard code its default values.
This avoids misleadings when reading the sources.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This should reduce concurrent accessing in SMP case.
Suggestion by Tord Romstad.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Both with added comment and changing the API to
reflect that only destination square and moved piece
is important for history.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Aspiration window search must be disabled for
multi-pv case.
We missed one point where aspiration window should
be disabled in this case.
Patch from Joona, with a little added edit by me.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Use a better condition to find candidate direct check pawns.
In particular consider only pawns in the front ranks of the
enemy king, this greatly reduces pawns candidates bitboard
that now is empty more then 90% of the time so that we
can early skip further tests.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Be more strict, is not enough dc bitboard is not empty, but
needs to inclde also at least one pawn.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
