Performance on Spacemit K3, thanks @edolnx for testing
master:
Total time (ms) : 65200
Nodes searched : 3493826
Nodes/second : 53586
riscv-scalable-port:
Total time (ms) : 15834
Nodes searched : 3493826
Nodes/second : 220653
Also thanks to @camel-cdr for guidance on RVV programming, and https://cloud-v.co for supplying an RVV instance to test with
passed STC:
LLR: 2.81 (-2.94,2.94) <0.00,2.00>
Total: 1152 W: 527 L: 108 D: 517
Ptnml(0-2): 0, 17, 167, 348, 44
https://tests.stockfishchess.org/tests/view/6a39895b3036e45021aeb368
## Summary
We've had a `riscv64` target for a while, but haven't really optimized for it, in particular the vector extension (RVV).
RVV, like SVE, is based on a scalable vector system where the vector length ranges from 128 to 65536. In practice implementations are between 128 and 2048, and 256 bits is quite common (e.g. the Spacemit K3 system above). Unfortunately this doesn't fit well into the rest of our code which assumes a fixed vector length, so what I've done is bypass the `VECTOR` ifdef (which now basically means "FIXED_LENGTH_VECTOR") and just have RVV-specific paths.
The ability to explicitly control `vl` makes the code quite readable, in my opinion. We use LMUL>1 in most places to take advantage of multi-vector instructions. Generally the LMULs were chosen to best support a 256-bit vlen, which is very common, but by virtue of how the vlen control works, the code works with any vlen. In a couple places, i.e., `get_changed_pieces` and `AffineTransformSparseInput::propagate`, we have separate implementations depending on the vlen, because the optimal LMUL varies a lot between implementations.
One little wrinkle is that `load_as` is compiled to a sequence of byte loads, because although unaligned loads are legal in RVA23, the spec says that they *may* be extremely slow (even though they usually aren't, in actual hw), so compilers are conservative. Thus I aligned the relevant buffers and made the semantics of `load_as` that the operand is aligned, by adding a runtime assertion.
### Universal binary
Adding a universal binary is pretty easy and we can just cross-compile. There are two targets: baseline rv64gc and riscv64-rva23, which is actually a smaller subset of RVA23 that also works on some older processors that don't support the full thing. We use clang because GCC, until recently, has a nasty bug with LTO and RVV.
Like the universal ARM and x86 builds, we check all the builds in CI. In this case we run bench with multiple vlens, 128 through 1024.
In the meantime I deleted the existing broken and unused riscv64 tests.
### Follow-ups
- Optimizations
- zvdot4a8i path
closes https://github.com/official-stockfish/Stockfish/pull/6920
No functional change
Pin every external action used by the root GitHub workflow set to a full-length
commit SHA and keep the selected release tag as a same-line comment.
Update the root workflows to the latest stable tagged action versions found
during the audit while preserving existing release guards, permissions, and
reusable workflow wiring.
closes https://github.com/official-stockfish/Stockfish/pull/6754
No functional change.
Fixes https://github.com/official-stockfish/Stockfish/issues/5564
This patch extracts the net downloading script in Makefile into an
external script file. Also the script is moderately rewritten for
improved readability and speed.
* Use wget preferentially over curl, as curl is known to have slight
overhead.
* Use command instead of hash to check if command exists. Reportedly,
hash always returns zero in some POSIX shells even when the command
fails.
* Command existence checks (wget/curl, sha256sum) are performed only
once at the beginning.
* Each of common patterns is encapsulated in a function
(get_nnue_filename, validate_network).
* Print out error/warning messages to stderr.
closes https://github.com/official-stockfish/Stockfish/pull/5563
No functional change
Co-authored-by: Disservin <disservin.social@gmail.com>
do not upload some unneeded intermediate directories,
disable running authenticated git commands with the checkout action.
Thanks to Yaron A for the report.
closes https://github.com/official-stockfish/Stockfish/pull/5435
No functional change
The same functionality is available by using COMPCXX and having another variable which does the same is just confusing.
There was only one mention on Stockfish Wiki about this which has been changed to COMPCXX.
closes https://github.com/official-stockfish/Stockfish/pull/5154
No functional change
This refactors the CI workflows to group some
logic and makes sure that all (pre)release
binaries are actually tested.
The screenshot below shows the execution logic of
the reworked ci,
https://github.com/Disservin/Stockfish/actions/runs/7773581379.
You can also hover over the cards to see the
execution flow.
The `matrix.json` and `arm_matrix.json` define the
binaries which will be uploaded to GitHub.
Afterwards a matrix is created and each job
compiles a profile guided build for that arch and
uploads that as an artifact to GitHub. The
Binaries/ARM_Binaries workflow's are called when
the previous step has been completed, and uploads
all artifacts to the (pre)release.
This also fixes some indentations and renames the
workflows, see
https://github.com/official-stockfish/Stockfish/actions,
where every workflow is called `Stockfish` vs
https://github.com/Disservin/Stockfish/actions. It
also increases the parallel compilation used for
make from `-j2 to -j4`.
It now also prevents the prerelease action from
running on forks.
A test release can be viewed here
https://github.com/Disservin/Stockfish/releases.
closes https://github.com/official-stockfish/Stockfish/pull/5035
No functional change
