Function w8a16_pipelined_prefers_m32 

pub fn w8a16_pipelined_prefers_m32(
    m: u32,
    k: u32,
    m32_kernel: KernelHandle,
) -> bool

2026-09-25: The selection rule between the 128-tile w8a16_gemm_pipelined and its 32-tile twin at a contiguous call site: the twin takes 1..=32 rows when its handle is nonzero and K is a positive multiple of 128. Above 32 rows the twin would need grid.y > 1, streaming the weight once per 32-row tile. w8a16_gemm_pipelined_by_m applies it.