[UR] Static OpenCL adapter (#21983)
Builds the OpenCL adapter as a static library embedded in the UR loader
instead of a separate runtime-loaded .so/.dll. Controlled by
UR_STATIC_ADAPTER_OPENCL (default ON for SYCL builds). The OpenCL ICD
itself is still resolved dynamically at runtime, so there's no OpenCL
link-time dependency.
Key changes
- Dynamic ICD loading — new ocl_dynamic_lib.{cpp,hpp} loads the ICD at
init: LoadLibraryExA("OpenCL.dll", LOAD_LIBRARY_SEARCH_SYSTEM32) on
Windows, dlopen("libOpenCL.so.1") (→ libOpenCL.so) on Linux, resolving
entry points through function pointers (core_functions.def, new
ocl_functions.def).
- Namespace isolation — all adapter entry points moved into namespace
ur::opencl to avoid symbol collisions; the loader wires DDI tables
directly via ur::opencl::urGet*ProcAddrTable.
- Loader integration — under UR_STATIC_ADAPTER_OPENCL the adapter is
probed/registered in-process (no adapter dlopen), and discarded cleanly
when no platforms are present (ur_loader.cpp, ur_adapter_registry.hpp,
loader/CMakeLists.txt).
- Build/linking control — opencl/CMakeLists.txt builds the static lib,
drops the OpenCL link, and zeroes UR_APIEXPORT/UR_APICALL/UR_DLLEXPORT
so definitions carry no __declspec(dllimport/dllexport).
BuildUnifiedRuntime.cmake forces the option on, propagates it into the
Windows ExternalProject, and suppresses the now-nonexistent
ur_adapter_opencl.dll in the copy/install logic.
- SYCL runtime — os_util.hpp: with the adapter static, __SYCL_OCL_CALL
probes libOpenCL.so.1/libOpenCL.so for clRetain*/clRelease* directly
(the libur_adapter_opencl.so it used to look them up in no longer
exists);
