Macro register_fused 

macro_rules! register_fused {
    (
        $registry:expr,
        $id:expr,
        $backend:expr,
        $dtypes:expr,
        $kernel:expr,
        cost = $cost:expr,
        precision = $precision:expr
        $(, caps = $caps:expr)?
        $(, revision = $revision:expr)?
        $(,)?
    ) => { ... };
}

Register a BackendImpl into a FusedKernelRegistry via the step-6 macro shape. Hides the boilerplate of constructing the BackendImpl struct so registration sites read as a flat list of (id, backend, dtypes, kernel, cost, precision) tuples.

Caps default to KernelCaps::empty() and revision to KernelRevisionHash::UNTRACKED; pass caps = ... and revision = ... to override.

Examples

register_fused!(
    registry,
    FusedOps::FUSED_LINEAR,
    BackendId::Cpu,
    &[F32, F32, F32, F32],
    fused_linear_f32_cpu_wrapper,
    cost = cost_fused_linear_cpu,
    precision = PrecisionGuarantee::REFERENCE,
);