Function dense_gemm_router 

pub fn dense_gemm_router(
    gpu: &dyn GpuBackend,
    kernel: KernelHandle,
    input: DevicePtr,
    weight: &DenseWeight,
    output: DevicePtr,
    m: u32,
    n: u32,
    k: u32,
    stream: u64,
) -> Result<()>

2026-09-25: Register-blocked BF16 GEMM (kernel dense_gemm_bf16_router) that keeps the scalar dense_gemm_bf16’s per-output FP32 accumulation order, strict k = 0..K-1, and with it the scalar kernel’s results under the --fmad=false build (kernels/gb10/common/KERNEL.toml). router_gate_gemm_dense uses it for the MoE router gate GEMM.