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ROCm sibling of lux-cuda implementing backend_api.h. Real path mirrors the CUDA plugin via HIP runtime + module API + hiprtc (non-deprecated hipSetDevice device model); stub path on hosts without ROCm reports is_available()==0. Builds as a dlopen'd MODULE (lux_hip.plugin). Real compute needs AMD/ROCm hardware.
2.2 KiB
lux-hip — HIP (AMD ROCm) backend plugin for lux-accel
lux-hip (CMake project lux-hip, v0.1.x) is a plugin (shared library /
CMake MODULE, output lux_hip.plugin) that lux-accel loads at runtime via
dlopen + lux_backend_init. It links nothing from lux-accel — it only
consumes the backend_api.h header. It is the ROCm sibling of lux-cuda.
On systems without the ROCm/HIP toolkit it builds as a no-op stub whose
is_available() returns 0, so the host transparently picks another backend.
Where things are
src/hip_plugin.cpp— the whole backend. The real path (#if LUX_HAS_HIP) mirrorslux-cudaalmost line-for-line: HIP runtime + module API +hiprtcmap 1:1 onto CUDA runtime/driver + NVRTC, which is what keeps the two backends byte-for-byte parity-testable from the same harness. It uses the non-deprecated runtime device model (hipSetDevice) rather than explicithipCtx*contexts.test/test_load.cpp— load/identity smoke test; runs a real HIP vector-add when ROCm hardware is present.conanfile.py,CMakeLists.txt,.gitignore.
Hardware requirement (honest status)
HIP has no runtime on Apple/macOS. On this Mac the plugin compiles and is
exercised only via the stub path (load + self-identify as type=HIP,
name="hip", is_available()==0). The real ROCm path compiles and runs only on
an AMD GPU with ROCm installed — that is a hardware limit, not skipped work.
To run the real backend (build hosts evo / spark with AMD + ROCm):
cmake -B build -DCMAKE_BUILD_TYPE=Release \
-DCMAKE_PREFIX_PATH=/opt/rocm \
-DLUXACCEL_INCLUDE_DIR=/path/to/lux-accel/include
cmake --build build -j
ctest --test-dir build --output-on-failure # runs the HIP vector-add
CMake links hip::host (+ hiprtc) and defines LUX_HAS_HIP=1 when
find_package(hip) resolves; otherwise it prints the stub notice.
Registration
The backend type is registered in lux-accel's enums as LUX_BACKEND_TYPE_HIP=4
(backend_api.h), LUX_BACKEND_HIP=4 (c_api.h), and
lux::gpu::BackendType::HIP (lux-gpu/gpu.hpp). The cross-backend conformance
harness (lux-gpu-conformance) lists it as one row in kBackends[].