llama : scale moe down projection per expert token (#30861)
* llama : scale moe down projection per expert token
Replace the global amax rescaling for the MoE down projection with a per-expert-token factor computed by a POOL_1D max reduction along the intermediate dimension. Undo the scale on the output with the same exact power-of-two factor. Handle POOL_1D in the Meta split-state logic so a split along axis 0 becomes a replicated per-device partial result, enabling tensor parallelism.
Assisted-by: pi:llama.cpp/ggml-org/DeepSeek-V4-Flash-Vision-Exp-GGUF (Mac Studio, M2 Ultra, 192GB)
* cont : simplify comments
Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
* llama : refactor amax src1 scaling result
Return the rescaled activation and the optional scale tensor through a small struct instead of an output pointer.
Assisted-by: pi:llama.cpp/ggml-org/DeepSeek-V4-Flash-Vision-Exp-GGUF (Mac Studio, M2 Ultra, 192GB)
* cont : add TODO + clean-up
