Function quantize_bf16_to_fp8 

pub fn quantize_bf16_to_fp8(
    gpu: &dyn GpuBackend,
    kernel: KernelHandle,
    input: DevicePtr,
    output: DevicePtr,
    row_scales: DevicePtr,
    n: u32,
    k: u32,
    stream: u64,
) -> Result<()>

Quantize a BF16 weight matrix [N, K] to FP8 E4M3 [N, K] with per-row f32 scales [N]. One CTA per row, 256 threads — parallel absmax reduction over K, then per-element saturating cast to E4M3.

Called once at model load time, never on the decode hot path.

Phase G (DFlash drafter FP8): converts each BF16 q/k/v/o/gate/up/down weight at load time. Decode path then consumes the resulting Fp8DenseWeight via fp8_gemm_n128.

Kernel: quantize_bf16_to_fp8(input, output, row_scales, N, K) — kernels/gb10/common/dense_gemv_fp8w.cu:36. Grid: (N, 1, 1) Block: (256, 1, 1)