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"""OpenCL-owned backend hooks."""

from pathlib import Path

from tvm_ffi.libinfo import load_lib_ctypes

from tvm.base import _LOADED_LIBS


def _detect_target_from_device(dev):
    from tvm.target import Target  # pylint: disable=import-outside-toplevel

    return Target(
        {
            "kind": "opencl",
            "max_shared_memory_per_block": dev.max_shared_memory_per_block,
            "max_threads_per_block": dev.max_threads_per_block,
            "thread_warp_size": dev.warp_size,
        }
    )


def register_backend():
    """Register OpenCL-owned Python semantics."""
    from tvm.target.detect_target import register_device_target_detector

    runtime_dir = Path(_LOADED_LIBS["tvm_runtime"]._name).resolve().parent
    try:
        # Runtime sidecars only need registration side effects; libtvm_runtime is global.
        _LOADED_LIBS["tvm_runtime_opencl"] = load_lib_ctypes(
            package="tvm",
            target_name="tvm_runtime_opencl",
            extra_lib_paths=[runtime_dir],
            mode="RTLD_LOCAL",
        )
    except (OSError, FileNotFoundError, RuntimeError):
        pass
    register_device_target_detector("opencl", _detect_target_from_device)
    return None


__all__ = ["register_backend"]
