zhanchangbao-sanechips opened a new pull request, #51340:
URL: https://github.com/apache/arrow/pull/51340
### What changes were proposed in this pull request?
Add initial RISC‑V Vector (RVV) support to Arrow C++. This mirrors the
existing SVE dynamic‑dispatch support on AArch64, aves the way for upcoming
RVV‑related optimizations, providing:
- Runtime CPU capability detection for RVV and vector length (VLEN =
128/256/512 bits) on riscv64 Linux.
- A `DispatchLevel::RVV` entry so RVV‑optimized kernels can be compiled with
`-march=rv64gcv` and selected at runtime.
- CMake flags: `ARROW_SIMD_LEVEL=RVV` for compile‑time RVV and
`ARROW_RUNTIME_SIMD_LEVEL=RVV|MAX` for runtime dispatch, with graceful fallback
(`NONE`) when the toolchain lacks RVV support.
### changes:
- `cpp/src/arrow/util/cpu_info.h/.cc`: add
`RVV/RVV128/RVV256/RVV512`hardware flags; detect V extension via
`getauxval(AT_HWCAP)` and VLEN via the `vlenb` CSR on Linux/riscv64.
- `cpp/src/arrow/util/dispatch_internal.h`: add `DispatchLevel::RVV` and
`ARROW_DISPATCH_TARGET_RVV` macro, wired into
`DynamicDispatch::IsSupported`.
- `cpp/cmake_modules/DefineOptions.cmake`: add `RVV` to `ARROW_SIMD_LEVEL`
and `ARROW_RUNTIME_SIMD_LEVEL` option lists.
- `cpp/cmake_modules/SetupCxxFlags.cmake`: riscv64 handling — check
`-march=rv64gcv`, set `ARROW_HAVE_RVV` (compile‑time) /
`ARROW_HAVE_RUNTIME_RVV` (runtime), default `ARROW_SIMD_LEVEL=NONE`.
- `cpp/src/arrow/util/simd.h`: include `<riscv_vector.h>` when RVV is
enabled.
- `cpp/src/arrow/util/io_util_test.cc`: extend `CpuInfo.Basic` to assert RVV
detection and a matching VLEN flag.
### How was this patch tested?
- Tested on a Sophgo SG2044 board with GCC 14.3.1.
- Built with --DARROW_SIMD_LEVEL=RVV -DARROW_RUNTIME_SIMD_LEVEL=RVV, config
passed.
- All unittest passed.
<img width="795" height="700" alt="20260915151437044"
src="https://github.com/user-attachments/assets/72d44824-a3b2-4956-9cbd-2dea8230eb5e";
/>
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
