It has more sense to treat the two evaluation metrics
in the same way.
As a side effect now we use the correct eval margin when
pruning in a SplitPoint node.
No functional change in single thread.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Rewrite sp_search() to have same signature of search()
This is the first prerequistite step toward unification.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Actually it is an error to update back moveCount value after split()
because it is used in update_history() to access movesSearched[]
array. But becasue this vector is not updated in the split point
we end up with an access of stale data.
Bug has been hidden til now because we 'forgot' to update
moveCount before returning from split().
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Mostly suggested by Justin (UncombedCoconut), the 0ULL -> 0 conversion
is mine.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Language guarantees that c'tor is called, but without any c'tor
it happens to work by accident because OS zeroes out the freshly
allocated pages. The problem is that if I deallocate and allocate
again, the second time pages are no more newly come by the OS and
so could contain stale info.
A practical case could be if we change TT size or numbers of
threads on the fly while already running.
Bug spotted by Justin Blanchard.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Fix release to workaround chess960 on some GUIs
Signature is:
stockfish bench 128 1 12 default depth
Node counts: 10914593
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Get rid of macros and use templates instead,
this is safer and allows us fix the warning:
ISO C++ forbids braced-groups within expressions
That broke compilation with -pedantic flag under
gcc and POPCNT enabled.
No functional and no performance change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This patch from Joona greatly reduces move count pruning,
below is the old and new move count limits starting from
ONE_PLY with half-play increment:
Old: 4,5,5,5, 7, 7,11,11,11,19,19,19,35,35
New: 4,5,7,9,12,15,19,23,28,33,39,45,52,59
Surprisingly results are even a bit better at a quite
fast time control.
After 5260 games at 30"+0.1
Mod - Orig: 864 - 806 - 3590 ELO +3 (+- 3.8)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
It seems totally unuseful because killers are not
used to order the moves in qsearch. Although there
is some functionality change, probably just a small
side effect.
After 5656 games on rc
Mod vs Orig: 1007 - 980 - 3669 ELO +1 (+- 3.7)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
So there is no need to explicitly check for king moves
when detecting prunable evasions.
Perhaps teoretically a very bit slower (I didn't test),
but it is more clear now what evasions we consider prunable.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Greatly cleanup SEE code and now it is also a bit
faster on gcc, about +0.6%.
Thanks to Mike Whiteley new SEE code that gave me
fresh ideas on how to cleanup this old stuff.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
A code semplification that could even be a slight increase,
anyhow is a reducing pruning patch, so it is good even
at equal strenght.
After 6342 games
Mod - Orig: 1040 - 974 - 4328 ELO +3 (+- 3.5)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Were removed when merged from Glaurung 2.2, but without
any test.
Note that weight has been increased from original 2 to 4 and
has been also fixed a bug where in the original version were
considered also diagonal sqaures for the rook, that are
contact squares but not checks.
After 4449 games at 30"+0.1
Mod - Orig: 717 - 649 - 3083 ELO +5 (+- 4.1)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Use the tail of moves[] array to store bad captures.
No functional change but some move reorder. Verified with old perft.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
And also other check bonuses.
After 4272 games on russian cluster at 30"+0.1
Mod - Orig: 711 - 612 - 2949 ELO +8 (+- 4.2)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
More then 100 lines of almost useless evaluations. Prefer
code semplification to a very small and dubious advantage.
After 7457 games on russian cluster:
Mod - Orig: 1285 - 1334 - 4838 ELO -2 (+- 3.2)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
And rename in nodes now that we have only one.
After the beta-cut off counters removing we can
get rid also of this one.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
For now keep FutilityMarginsMatrix[] unchanged, in
future we are going to reduce to compensate for extra
margin.
At this moment it is enough we don't have regressions.
After 9694 games on russian cluster
Mod - Orig 1608 - 1578 - 6508 ELO +1 (+- 2.8)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Instead of one comparison in while() condition use two,
the first to check if the piece is exsistant and the second
to loop across pieces of that type.
This should help branch prediction in cases we have only
one piece of the same type, for instance for queens, the
first branch is always true and the second is almost always
false.
Increased speed of 0.3-0.5 % on Gcc pgo compiles.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
