llama.cpp

20688a1c - metal : support n_kv_max sparse mask hint in flash attention vec kernel

metal : support n_kv_max sparse mask hint in flash attention vec kernel - add kernel_flash_attn_ext_vec_idx: compacts finite mask entries into a per-row index list (Hillis-Steele scan, one threadgroup per row) - extend vec FA kernel with optional sparse index gathering (FC slot 5) - add host-side gate: sparse path when n_kv_max > 0, mask present, supported head sizes / KV types, n_kv_max <= 4096 - new buffer region extra_idx for the index list - pipeline getter extended with has_sparse param - add test cases: head sizes, quant types, nb>1, nr23 variants, sinks, ALiBi, softcap, permute, v_view_of_k, no-mask fallback Note: multi-row (nb*nr23[1] > 1) cases still failing - rid mapping in the store phase needs revisiting for the sparse path. Assisted-by: pi:llama.cpp/Qwen3.8-27B