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>
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>
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>
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>
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>
Centralize in a single object all the global resources
management and avoid a bunch of sparse exit() calls.
This is more reliable and clean and more stick to C++ coding
practices.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Note that some pawns and material info has been switched
to int from int8_t.
This is a waste of space but it is not clear if we have a
faster or slower code (or nothing changed), some test should be
needed.
Few warnings still are alive.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Prune more moves after a null search because of
a lower beta limit then in main search.
In test positions reduces the searched nodes of 30% !!!!
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
They hide the underlying uniform function call with
no benefit.
A little bit more verbose but now is clear what happens.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
For queen mobility could be bigger then 15, so
we need count_1s() not count_1s_max_15().
This bug was introduced by patch:
"Group common evaluate code" of 24/9/2008
So it's almost 4 months and two release old!
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Do not consider squares protected by enemy pawns
in mobility evaluation.
This reduces the mobility value by about 15%
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Is a new evaluation rule that gives bonus in midgame
to the side that has more space behind pawns for its
minor pieces.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
After deep test (1000 games) it seems do not improve anything,
actually seems slightly weaker.
So remove it for now.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
There are subtle differences in the king evaluation
that should be clear to avoid misunderstandings.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>