Constant MOE_ROUTER_GEMM_MAX_PREFILL_ROWS 

pub const MOE_ROUTER_GEMM_MAX_PREFILL_ROWS: u32 = 64;

2026-10-01: Most rows for which the MoE prefill router takes moe_router_gemm (the decode routers’ kernel, the same bits as dense_gemm_router); the decode routers run it at 2 to 64 rows.