It should be used slavesMask.count() instead.
Verified 100% equivalent when sp->allSlavesSearching:
dbg_hit_on(sp->allSlavesSearching, sp->slavesCount != sp->slavesMask.count());
No functional change.
Document and clarify that we cannot rejoin on ourselves
and that we never late join if we are master and all
slaves have finished, inded in this case we exit idle_loop.
No functional change.
In case of Threads.size() == 2 we have that sp->allSlavesSearching
is always false (because we have finished our search), bestSp is
always NULL and we never late join, so there is no need to special
case here.
Tested with dbg_hit_on(sp && sp->allSlavesSearching) and
verified it never fires.
No functional change.
And retire a redundant field. This is important also
from a concept point of view becuase we want to keep
SMP structures as simple as possible with the only
strictly necessary data.
Verified with
dbg_hit_on(sp->spLevel != level)
that the values are 100% the same out of more 50K samples.
No functional change.
Balance threads between split points.
There are huge differences between different machines and autopurging makes it very difficult to measure the improvement in fishtest, but the following was recorded for 16 threads at 15+0.05:
For Bravone (1000 games): 0 ELO
For Glinscott (1000 games): +20 ELO
For bKingUs (1000 games): +50 ELO
For fastGM (1500 games): +50 ELO
The change was regression for no one, and a big improvement for some, so it should be fine to commit it.
Also for 8 threads at 15+0.05 we measured a statistically significant improvement:
ELO: 6.19 +-3.9 (95%) LOS: 99.9%
Total: 10325 W: 1824 L: 1640 D: 6861
Finally it was verified that there was no (significant) regression for
4 threads:
ELO: 0.09 +-2.8 (95%) LOS: 52.4%
Total: 19908 W: 3422 L: 3417 D: 13069
2 threads:
ELO: 0.38 +-3.0 (95%) LOS: 60.0%
Total: 19044 W: 3480 L: 3459 D: 12105
1 thread:
ELO: -1.27 +-2.1 (95%) LOS: 12.3%
Total: 40000 W: 7829 L: 7975 D: 24196
Resolves#258
This micro-optimization only complicates the code and provides no benefit.
Removing it is even a speedup on my machine (i7-3770k, linux, gcc 4.9.1):
stat test master diff
mean 2,403,118 2,390,904 12,214
stdev 12,043 10,620 3,677
speedup 0.51%
P(speedup>0) 100.0%
No functional change.
Use integer arithmetic instead of floating point arithmetic.
Floating point arithmetic was causing different results for some 32-bit compiles
No functional change
Resolves#249Resolves#250
I went through all the individual compile options that differ between
-fprofile-generate/-fprofile-use and -fprofile-arcs/-fbranch-probabilities
and distilled the speed difference down to only turning off
-fno-peel-loops and -fno-tracer. Using this we still get the full speedup
(maybe a bit more because other optimizations stay on) and it's also much cleaner
because we can get rid of the "@rm -f ucioption.gc*" hack for all versions of gcc.
No functional change.
Resolves#237
This is an old patch from Jean-Francois Romang to send
UCI hashfull info to the GUI:
https://github.com/mcostalba/Stockfish/pull/60/files
It was wrongly judged as a slowdown, but it takes much
less than 1 ms to run, indeed on my core i5 2.6Ghz it
takes about 2 microsecs to run!
Regression test is good:
STC
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 7352 W: 1548 L: 1401 D: 4403
LTC
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 61432 W: 10307 L: 10251 D: 40874
I have set the name of the author to the original
one.
No functional change.
This patch has two positive effects:
- Retire a hackish formula and leave
just a natural, simple and plain one.
- Reduce strenght at very low level, but
don't impact medium/high levels.
Actually even at level 0, SF is still too
strong for many beginners (this was reported
many times for instance on Droidfish user
comments on Google Play).
Test on fishtest shows that ELO drop is around
170 ELO at level 0 (good!), 130 ELO at level 1
and smoothly reduces (as expected) until level
10 where the drop is just of 8 ELO.
No functional change.
- Fix a skill level problem: Don't allow move pruning at root node
- Revert "Fix profile build for gcc on Mac OSX". Results for a faster binary in x86-64.
- Fix a MSVC warning
Bench: 8918745
Seems to be a performance regression for standard build.
For SF6 people compiling on Mac OSX using profile-build option
just need to make necessary adjustments manually...
No functional change
Resolves#223
Warning is C4512 (assignment operator could not be generated)
Now, apart the foreign syzygy code, everything compiles
without warnings at warning level 4.
Backported from C++11 branch.
No functional change.
- Fix a compilation issue related to BMI2 PEXT instruction
- Retrieve a ponder move from TT if PV is only one move long
Bench: 8080602
No functional change
This intrinsic to call BMI2 PEXT instruction is
defined in immintrin.h. This header should be
included only when USE_PEXT is defined, otherwise
we define _pext_u64 as 0 forcing a nop.
But under some mingw platforms, even if we don't
include the header, immintrin.h gets included
anyhow through an include chain that starts with
STL <algorithm> header. So we end up both defining
_pext_u64 function and at the same time defining
_pext_u64 as 0 leading to a compile error.
The correct solution is of not using _pext_u64 directly.
This patch fixes a compile error with some mingw64
package when compiling with x86-64.
No functional change.
Resolves#222
In case we stop the search during a fail-high
it is possible we return to GUI without a ponder
move. This patch try harder to find a ponder move
retrieving it from TT. This is important in games
played with 'ponder on'.
bench: 8080602
Resolves#221
On platforms where size_t is 32 bit, we
can have an overflow in this expression:
(mbSize * 1024 * 1024)
Fix it setting max hash size of 2GB on platforms
where size_t is 32 bit.
A small rename while there: now struct Cluster
is definied inside class TranspositionTable so
we should drop the redundant TT prefix.
No functional change.
On Android-ARM current TB code crashes at
random times even in single thread mode.
Reported, debugged, fixed and verified
by Peter Osterlund.
No functional change.
Resolves#201
This optimization is aimed at old hardware only (withouth popcount), and even on
non popcount compile (ARCH=x86-64), it provides no mesurable speedup:
stat test master diff
mean 2,341,779 2,354,699 -12,920
stdev 12,910 14,770 18,150
speedup -0.55%
P(speedup>0) 23.8%
No functional change.
Resolves#187
