model: M3: Move MSA into a new memory implementation (#26338)

* Move MSA logic from llama-kv-cache into llama-kv-cache-msa

* cont : minor

* cont : ws fix

---------

Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>

src/llama-graph.h

@@ -23,6 +23,7 @@ struct llama_memory_context_i;
 
 class llama_kv_cache_context;
 class llama_kv_cache_dsa_context;
+class llama_kv_cache_msa_context;
 class llama_kv_cache_dsv4_raw_context;
 class llama_kv_cache_dsv4_context;
 class llama_kv_cache_iswa_context;
@@ -425,6 +426,26 @@ public:
     const llama_kv_cache_dsa_context * mctx;
 };
 
+// standard K/V attention input against the base cache, plus destination indices for the indexer key cache
+class llm_graph_input_attn_kv_msa : public llm_graph_input_attn_kv {
+public:
+    llm_graph_input_attn_kv_msa(
+            const llama_hparams & hparams,
+            const llama_cparams & cparams,
+            const llama_kv_cache_msa_context * mctx);
+    ~llm_graph_input_attn_kv_msa() = default;
+
+    void set_input(const llama_ubatch * ubatch) override;
+
+    bool can_reuse(const llm_graph_params & params) override;
+
+    ggml_tensor * get_k_idxs_idx() const { return self_k_idxs_idx; }
+
+    ggml_tensor * self_k_idxs_idx = nullptr; // I64 [n_batch]
+
+    const llama_kv_cache_msa_context * mctx_msa;
+};
+
 class llm_graph_input_attn_kv_iswa : public llm_graph_input_i {
 public:
     llm_graph_input_attn_kv_iswa(
@@ -1169,6 +1190,8 @@ struct llm_graph_context {
 
     llm_graph_input_attn_k_dsa * build_attn_inp_k_dsa() const;
 
+    llm_graph_input_attn_kv_msa * build_attn_inp_kv_msa() const;
+
     ggml_tensor * build_attn(
             llm_graph_input_attn_k_dsa * inp,
             ggml_tensor * wo,