After merging the HalfKA and Threats accumulators (7c7fe322) and the
subsequent removal of the double-incremental/fused update, a number of
NNUE helpers and fields became unreachable. Each was verified to have
zero callers/readers across the source tree:
- FusedUpdateData logic in FullThreats: the fused-update branch of
append_changed_indices and the FusedUpdateData parameter are unused;
the accumulator update no longer passes fused data.
- FullThreats::requires_refresh: never called. The live king-bucket
refresh check is HalfKAv2_hm::requires_refresh (PSQFeatureSet), used
in nnue_accumulator.
- HalfKAv2_hm::append_active_indices: never called. The live
active-index builder is FullThreats::append_active_indices
(ThreatFeatureSet).
- DirtyThreats::us, prevKsq and ksq: written in do_move but only read by
the now-removed FullThreats::requires_refresh. Removing them also
drops three stores from the do_move path.
- Unused feature Name constants and the unused FtOneVal / HiddenMaxVal
constants in nnue_common.h.
- Two stale feature-header banner comments.
closes https://github.com/official-stockfish/Stockfish/pull/6898
No functional change
example of using, to avoid mixed usage of std::uint/std::int and uint/int...
```cpp
using u64 = std::uint64_t;
using u32 = std::uint32_t;
using u16 = std::uint16_t;
using u8 = std::uint8_t;
using i64 = std::int64_t;
using i32 = std::int32_t;
using i16 = std::int16_t;
using i8 = std::int8_t;
using usize = std::size_t;
using isize = std::ptrdiff_t;
#if defined(__GNUC__) && defined(IS_64BIT)
__extension__ using u128 = unsigned __int128;
__extension__ using i128 = signed __int128;
#endif
```
closes https://github.com/official-stockfish/Stockfish/pull/6874
No functional change
I found these changes useful and natural when working on a patch to improve mate reporting. I can revert some of the changes if maintainers would prefer that. E.g. I am not sure whether `unset_bound_flags()` is worth defining.
closes https://github.com/official-stockfish/Stockfish/pull/6785
No functional change
Passed STC
https://tests.stockfishchess.org/tests/view/69e82e200e9667dd5a765631
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 115424 W: 29950 L: 29822 D: 55652
Ptnml(0-2): 318, 12712, 31544, 12800, 338
Passed AVX2-only STC
https://tests.stockfishchess.org/tests/view/69e953080e9667dd5a7657c0
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 134720 W: 34773 L: 34665 D: 65282
Ptnml(0-2): 344, 14958, 36694, 14974, 390
Now that our L1 size is much smaller, the overhead of tracking diffs for
`double_inc_update` is a larger share of the cost.
Interestingly ces42 measured a -0.9% slowdown locally (avxvnni build).
Meanwhile Torom and I find this branch to be 2% faster. I'm not sure exactly
what's going on but more tests may be in order
closes https://github.com/official-stockfish/Stockfish/pull/6776
No functional change
LLR: 2.97 (-2.94,2.94) <0.00,2.00>
Total: 38400 W: 10057 L: 9749 D: 18594
Ptnml(0-2): 93, 4110, 10498, 4394, 105
https://tests.stockfishchess.org/tests/view/69d2073261a12cebe17edc04
compile time generation leads to sharing tables through the binary, resulting
in gain on fishtest, as well as reduced memory usage. The downside is slightly
longer compilation time.
Using pdep reduces table size 4x, and gains a little outside of fishtest as well.
closes https://github.com/official-stockfish/Stockfish/pull/6706
No functional change
STC
```
LLR: 5.45 (-2.94,2.94) <0.00,2.00>
Total: 612192 W: 158602 L: 157260 D: 296330
Ptnml(0-2): 1634, 67783, 166027, 68911, 1741
```
@Torom measured:
```
sf_base = 2380902 +/- 1016 (95%)
sf_test = 2391426 +/- 1065 (95%)
diff = 10524 +/- 1336 (95%)
speedup = 0.44203% +/- 0.056% (95%)
```
I've verified that `_mm512_slli_epi16(v, 0)` gets optimized out in GCC
9+ and clang 4+. Added constants to types.h so that people messing
around with the layout of `Move` don't have to know about this part of
the code.
closes https://github.com/official-stockfish/Stockfish/pull/6670
No functional change
Remove a couple unused things, mark `noRaysContaining` as
`[[maybe_unused]]` (suggested by Viz) to silence a warning on GCC 10,
update a comment, and replace inline constants
closes https://github.com/official-stockfish/Stockfish/pull/6460
No functional change
passed on avx512ICL:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 30240 W: 8026 L: 7726 D: 14488
Ptnml(0-2): 95, 3235, 8171, 3513, 106
https://tests.stockfishchess.org/tests/view/69281d9ab23dfeae38cfeeb8
passed on generic architectures:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 73184 W: 19183 L: 18821 D: 35180
Ptnml(0-2): 258, 7988, 19744, 8338, 264
https://tests.stockfishchess.org/tests/view/6928ba11b23dfeae38cff276
subsequent cleanups tested as:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 72480 W: 18678 L: 18502 D: 35300
Ptnml(0-2): 242, 7925, 19718, 8125, 230
https://tests.stockfishchess.org/tests/view/692a26adb23dfeae38cff566
We add an argument noRaysContaining, which skips all discoveries which contain
all bits in the argument; if the argument is from | to, then this will
eliminate the discovery. Separately, on AVX512ICL we can speed up the
computation of DirtyThreats by moving from a pop_lsb loop to a vector
extraction with vpcompressb. See PR for details.
closes https://github.com/official-stockfish/Stockfish/pull/6453
No functional change
[Passed STC](https://tests.stockfishchess.org/tests/live_elo/691fc321acb6dbdf23d07e4b):
```
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 215360 W: 55651 L: 55108 D: 104601
Ptnml(0-2): 520, 22399, 61290, 22960, 511
```
This PR is on top of ces42's work so I'll rebase if that PR changes.
Essentially, it comprises my adjustments to `make_index` that remained
unmerged before threat inputs was finalized.
The unsigned intermediate variables let us skip a bunch of useless sign
extensions (because Square and Piece inherit from `int8_t`, and C/C++
semantics require narrow integers to be promoted to `int` before doing
arithmetic on them). Additionally, by removing the special usage of
`offsets[][64]` and `[65]` the indexing becomes more efficient. (This
usage was a temporary hack from sscg anyway, so I think he'll like that
it's gone.) Finally, the `sf_assume` condition was fixed so that it
actually makes a difference to the compiler.
The speedup is fairly nice locally (combining both ces42's and these changes):
```
Result of 100 runs
==================
base (...kfish.master) = 1691982 +/- 1907
test (./stockfish ) = 1714349 +/- 1789
diff = +22367 +/- 2465
speedup = +0.0132
P(speedup > 0) = 1.0000
```
closes https://github.com/official-stockfish/Stockfish/pull/6445
No functional change
gcc 9.3
clang 10
using unsupported compiler versions will generate an error,
older version might miscompile SF
CI: improves output on failed bench output
closes https://github.com/official-stockfish/Stockfish/pull/6032
No functional change
- Capitalize comments
- Reformat multi-lines comments to equalize the widths of the lines
- Try to keep the width of comments around 85 characters
- Remove periods at the end of single-line comments
closes https://github.com/official-stockfish/Stockfish/pull/5469
No functional change
Passed STC:
https://tests.stockfishchess.org/tests/view/665ce3f8fd45fb0f907c537f
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 282784 W: 73032 L: 73082 D: 136670
Ptnml(0-2): 680, 31845, 76364, 31851, 652
Recently when I overhauled these comments, Disservin asked why these
were so much lower: they're a relic from when we had a third QS stage at
-5. Now we don't, so fix these to the obvious place.
I was fairly sure it was nonfunctional but ran the nonreg to be double
sure.
closes https://github.com/official-stockfish/Stockfish/pull/5343
Bench: 1057383
Also "fix" movepicker to allow depths between CHECKS and NO_CHECKS,
which makes them easier to tweak (not that they get tweaked hardly ever)
(This was more beneficial when there was a third stage to DEPTH_QS, but
it's still an improvement now)
closes https://github.com/official-stockfish/Stockfish/pull/5205
No functional change
Only Direction type is using two of the enable overload macros.
Aside from this, only two of the overloads are even being used.
Therefore, we can just define the needed overloads and remove the macros.
closes https://github.com/official-stockfish/Stockfish/pull/4966
No functional change.
The primary rationale behind this lies in the fact that enums were not
originally designed to be employed in the manner we currently utilize them.
The Value enum was used like a type alias throughout the code and was often
misused. Furthermore, changing the underlying size of the enum to int16_t broke
everything, mostly because of the operator overloads for the Value enum, were
causing data to be truncated. Since Value is now a type alias, the operator
overloads are no longer required.
Passed Non-Regression STC:
https://tests.stockfishchess.org/tests/view/6593b8bb79aa8af82b95b401
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 235296 W: 59919 L: 59917 D: 115460
Ptnml(0-2): 743, 27085, 62054, 26959, 807
closes https://github.com/official-stockfish/Stockfish/pull/4960
No functional change
- remove the blank line between the declaration of the function and it's
comment, leads to better IDE support when hovering over a function to see it's
description
- remove the unnecessary duplication of the function name in the functions
description
- slightly refactored code for lsb, msb in bitboard.h There are still a few
things we can be improved later on, move the description of a function where
it was declared (instead of implemented) and add descriptions to functions
which are behind macros ifdefs
closes https://github.com/official-stockfish/Stockfish/pull/4840
No functional change
This introduces clang-format to enforce a consistent code style for Stockfish.
Having a documented and consistent style across the code will make contributing easier
for new developers, and will make larger changes to the codebase easier to make.
To facilitate formatting, this PR includes a Makefile target (`make format`) to format the code,
this requires clang-format (version 17 currently) to be installed locally.
Installing clang-format is straightforward on most OS and distros
(e.g. with https://apt.llvm.org/, brew install clang-format, etc), as this is part of quite commonly
used suite of tools and compilers (llvm / clang).
Additionally, a CI action is present that will verify if the code requires formatting,
and comment on the PR as needed. Initially, correct formatting is not required, it will be
done by maintainers as part of the merge or in later commits, but obviously this is encouraged.
fixes https://github.com/official-stockfish/Stockfish/issues/3608
closes https://github.com/official-stockfish/Stockfish/pull/4790
Co-Authored-By: Joost VandeVondele <Joost.VandeVondele@gmail.com>
After removing classic evaluation VALUE_KNOWN_WIN is not anymore returned explicit evaluation. So remove and replace it with VALUE_TB_WIN_IN_MAX_PLY.
Measurement on my big bench (bench 16 1 16 pos1000.fen) verifies that at least with current net the calculated evaluation lies always in the open interval (-VALUE_KNOWN_WIN, VALUE_KNOWN_WIN).
So i consider this a non-functional change. But to be safe i tested this also at LTC as requested by Stephane Nicolet.
STC:
https://tests.stockfishchess.org/tests/view/64f9db40eaf01be8259a6ed5
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 455296 W: 115981 L: 116217 D: 223098
Ptnml(0-2): 1415, 50835, 123420, 50527, 1451
LTC:
https://tests.stockfishchess.org/tests/view/650bfd867ca0d3f7bbf25feb
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 35826 W: 9170 L: 8973 D: 17683
Ptnml(0-2): 12, 3523, 10645, 3722, 11
closes https://github.com/official-stockfish/Stockfish/pull/4792
Bench: 1603079
The commit removes all uses of ICC's __INTEL_COMPILER macro and other
references to ICC. It also adds ICX info to the compiler command and
fixes two typos in Makefile's help output.
closes https://github.com/official-stockfish/Stockfish/pull/4769
No functional change
a) Add further tests to CI to cover most features. This uncovered a potential race
in case setoption was sent between two searches. As the UCI protocol requires
this sent to be went the engine is not searching, setoption now ensures that
this is the case.
b) Remove some unused code
closes https://github.com/official-stockfish/Stockfish/pull/4730
No functional change
