Commit 84e66d032 for llama.cpp

commit 84e66d03218711dfcaa993e5f64a546abe82df9a
Author: Tarek Dakhran <tarek@liquid.ai>
Date:   Tue Oct 20 23:17:13 2026 +0200

    refactor : move LFM2 shortconv and FFN blocks into a shared LFM base (#30874)

    * llama : move LFM2 shortconv and FFN blocks into a shared LFM base

    * Update src/models/lfm-base.cpp

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

    ---------

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

diff --git a/src/models/lfm-base.cpp b/src/models/lfm-base.cpp
new file mode 100644
index 000000000..5e722eca8
--- /dev/null
+++ b/src/models/lfm-base.cpp
@@ -0,0 +1,114 @@
+#include "models.h"
+
+#include "llama-memory-recurrent.h"
+
+#include <algorithm>
+
+llm_build_lfm_base::llm_build_lfm_base(const llm_graph_params & params) : llm_graph_context(params) {}
+
+ggml_tensor * llm_build_lfm_base::build_lfm_shortconv(const llama_model & model,
+                                                      const llama_memory_recurrent_context * mctx_recr,
+                                                      llm_graph_input_rs * inp_recr,
+                                                      ggml_tensor * cur,
+                                                      int il) {
+    const uint32_t kv_head      = mctx_recr->get_head();
+    const int64_t  n_seq_tokens = ubatch.n_seq_tokens;
+    const int64_t  n_seqs       = ubatch.n_seqs;
+    GGML_ASSERT(n_seqs != 0);
+    GGML_ASSERT(ubatch.equal_seqs());
+    GGML_ASSERT(ubatch.n_tokens == n_seq_tokens * n_seqs);
+
+    GGML_ASSERT(hparams.n_shortconv_l_cache > 1);
+    const uint32_t d_conv = hparams.n_shortconv_l_cache - 1;
+    const int64_t  n_embd = hparams.n_embd;
+
+    // {n_embd, n_tokens} => {n_embd, n_seq_tokens, n_seqs}
+    cur = ggml_reshape_3d(ctx0, cur, cur->ne[0], n_seq_tokens, n_seqs);
+
+    auto * bcx = build_lora_mm(model.layers[il].shortconv.in_proj, cur);
+    cb(bcx, "model.layers.{}.conv.in_proj", il);
+
+    constexpr auto n_chunks = 3;
+    GGML_ASSERT(bcx->ne[0] % n_chunks == 0);
+    const auto chunk_size = bcx->ne[0] / n_chunks;
+    auto *     b          = ggml_view_3d(ctx0, bcx, chunk_size, bcx->ne[1], bcx->ne[2], bcx->nb[1], bcx->nb[2],
+                                         0 * chunk_size * ggml_element_size(bcx));
+    auto *     c          = ggml_view_3d(ctx0, bcx, chunk_size, bcx->ne[1], bcx->ne[2], bcx->nb[1], bcx->nb[2],
+                                         1 * chunk_size * ggml_element_size(bcx));
+    auto *     x          = ggml_view_3d(ctx0, bcx, chunk_size, bcx->ne[1], bcx->ne[2], bcx->nb[1], bcx->nb[2],
+                                         2 * chunk_size * ggml_element_size(bcx));
+
+    auto * bx = ggml_transpose(ctx0, ggml_mul(ctx0, b, x));
+
+    // read conv state
+    auto * conv_state = mctx_recr->get_r_l(il);
+    auto * conv_rs    = build_rs(inp_recr, conv_state, hparams.n_embd_r(), n_seqs);
+    auto * conv       = ggml_reshape_3d(ctx0, conv_rs, d_conv, n_embd, n_seqs);
+
+    // causal prepends the state, non-causal pads symmetrically for a centered window
+    if (hparams.causal_attn) {
+        bx = ggml_concat(ctx0, conv, bx, 0);
+    } else {
+        const int64_t pad = (hparams.n_shortconv_l_cache - 1) / 2;
+        auto * left = ggml_cont(ctx0,
+            ggml_view_3d(ctx0, conv, pad, n_embd, n_seqs, conv->nb[1], conv->nb[2], (d_conv - pad) * conv->nb[0]));
+        bx = ggml_pad_ext(ctx0, ggml_concat(ctx0, left, bx, 0), 0, pad, 0, 0, 0, 0, 0, 0);
+    }
+    GGML_ASSERT(bx->ne[0] > conv->ne[0]);
+
+    // write conv states: slot 0 = the final state, slot s = the state s tokens back (partial rollback)
+    const int64_t K         = hparams.causal_attn && cparams.n_rs_seq > 0 ? (int64_t) cparams.n_rs_seq + 1 : 1;
+    const int64_t n_written = std::min<int64_t>(n_seq_tokens, K);
+    const auto    mem_size  = mctx_recr->get_size();
+    const size_t  row_size  = ggml_row_size(conv_state->type, (int64_t) d_conv * n_embd);
+
+    for (int64_t slot = 0; slot < n_written; ++slot) {
+        auto * conv_snap = ggml_view_3d(ctx0, bx, d_conv, bx->ne[1], bx->ne[2], bx->nb[1], bx->nb[2],
+                                        (bx->ne[0] - d_conv - slot) * ggml_element_size(bx));
+        ggml_build_forward_expand(gf, ggml_cpy(ctx0, conv_snap,
+                                               ggml_view_2d(ctx0, conv_state, (int64_t) d_conv * n_embd, n_seqs,
+                                                            conv_state->nb[1],
+                                                            ((size_t) slot * mem_size + kv_head) * row_size)));
+    }
+
+    auto * conv_kernel = model.layers[il].shortconv.conv;
+    auto * conv_out    = ggml_ssm_conv(ctx0, bx, conv_kernel);
+    cb(conv_out, "model.layers.{}.conv.conv", il);
+
+    auto * y = ggml_mul(ctx0, c, conv_out);
+    y        = build_lora_mm(model.layers[il].shortconv.out_proj, y);
+    cb(y, "model.layers.{}.conv.out_proj", il);
+    // {n_embd, n_seq_tokens, n_seqs} => {n_embd, n_tokens}
+    y = ggml_reshape_2d(ctx0, y, y->ne[0], n_seq_tokens * n_seqs);
+
+    return y;
+}
+
+ggml_tensor * llm_build_lfm_base::build_lfm_dense_ffn(const llama_model & model,
+                                                      ggml_tensor * cur,
+                                                      int il) {
+    GGML_ASSERT(!model.layers[il].ffn_up_b);
+    GGML_ASSERT(!model.layers[il].ffn_gate_b);
+    GGML_ASSERT(!model.layers[il].ffn_down_b);
+    return build_ffn(cur,
+        model.layers[il].ffn_up,   NULL, NULL,
+        model.layers[il].ffn_gate, NULL, NULL,
+        model.layers[il].ffn_down, NULL, NULL,
+        NULL, LLM_FFN_SILU, LLM_FFN_PAR, il);
+}
+
+ggml_tensor * llm_build_lfm_base::build_lfm_moe_ffn(const llama_model & model,
+                                                    ggml_tensor * cur,
+                                                    int il) {
+    return build_moe_ffn(cur,
+            model.layers[il].ffn_gate_inp,
+            model.layers[il].ffn_up_exps,
+            model.layers[il].ffn_gate_exps,
+            model.layers[il].ffn_down_exps,
+            model.layers[il].ffn_exp_probs_b,
+            n_expert, n_expert_used,
+            LLM_FFN_SILU, true,
+            hparams.expert_weights_scale,
+            static_cast<llama_expert_gating_func_type>(hparams.expert_gating_func),
+            il);
+}
diff --git a/src/models/lfm2.cpp b/src/models/lfm2.cpp
index 942d8de90..dd61f509a 100644
--- a/src/models/lfm2.cpp
+++ b/src/models/lfm2.cpp
@@ -147,35 +147,11 @@ std::unique_ptr<llm_graph_context> llama_model_lfm2::build_arch_graph(const llm_

 template <bool iswa>
 llama_model_lfm2::graph<iswa>::graph(const llama_model & model, const llm_graph_params & params) :
-    llm_graph_context(params) {
+    llm_build_lfm_base(params) {
     using inp_hybrid_type = std::conditional_t<iswa, llm_graph_input_mem_hybrid_iswa,  llm_graph_input_mem_hybrid>;
     using inp_attn_type   = std::conditional_t<iswa, llm_graph_input_attn_kv_iswa,     llm_graph_input_attn_kv>;
     using mem_hybrid_ctx  = std::conditional_t<iswa, llama_memory_hybrid_iswa_context, llama_memory_hybrid_context>;

-    // lambda helpers for readability
-    auto build_dense_feed_forward = [&model, this](ggml_tensor * cur, int il) -> ggml_tensor * {
-        GGML_ASSERT(!model.layers[il].ffn_up_b);
-        GGML_ASSERT(!model.layers[il].ffn_gate_b);
-        GGML_ASSERT(!model.layers[il].ffn_down_b);
-        return build_ffn(cur,
-            model.layers[il].ffn_up, NULL, NULL,
-            model.layers[il].ffn_gate, NULL, NULL,
-            model.layers[il].ffn_down, NULL, NULL,
-            NULL, LLM_FFN_SILU, LLM_FFN_PAR, il);
-    };
-    auto build_moe_feed_forward = [&model, this](ggml_tensor * cur, int il) -> ggml_tensor * {
-        return build_moe_ffn(cur,
-                model.layers[il].ffn_gate_inp,
-                model.layers[il].ffn_up_exps,
-                model.layers[il].ffn_gate_exps,
-                model.layers[il].ffn_down_exps,
-                model.layers[il].ffn_exp_probs_b,
-                n_expert, n_expert_used,
-                LLM_FFN_SILU, true,
-                hparams.expert_weights_scale,
-                static_cast<llama_expert_gating_func_type>(hparams.expert_gating_func),
-                il);
-    };
     auto build_attn_block = [&model, this](ggml_tensor *   cur,
                                            ggml_tensor *   inp_pos,
                                            inp_attn_type * inp_attn,
@@ -207,82 +183,6 @@ llama_model_lfm2::graph<iswa>::graph(const llama_model & model, const llm_graph_

         return cur;
     };
-    auto build_shortconv_block = [&model, this](ggml_tensor *        cur,
-                                                llm_graph_input_rs * inp_recr,
-                                                int                  il) -> ggml_tensor * {
-        const auto * mctx_cur = static_cast<const mem_hybrid_ctx *>(mctx)->get_recr();
-        const uint32_t kv_head      = mctx_cur->get_head();
-        const int64_t  n_seq_tokens = ubatch.n_seq_tokens;
-        const int64_t  n_seqs       = ubatch.n_seqs;
-        GGML_ASSERT(n_seqs != 0);
-        GGML_ASSERT(ubatch.equal_seqs());
-        GGML_ASSERT(ubatch.n_tokens == n_seq_tokens * n_seqs);
-
-        GGML_ASSERT(hparams.n_shortconv_l_cache > 1);
-        const uint32_t d_conv = hparams.n_shortconv_l_cache - 1;
-
-        // {n_embd, n_tokens} => {n_embd, n_seq_tokens, n_seqs}
-        cur = ggml_reshape_3d(ctx0, cur, cur->ne[0], n_seq_tokens, n_seqs);
-
-        auto * bcx = build_lora_mm(model.layers[il].shortconv.in_proj, cur);
-        cb(bcx, "model.layers.{}.conv.in_proj", il);
-
-        constexpr auto n_chunks = 3;
-        GGML_ASSERT(bcx->ne[0] % n_chunks == 0);
-        const auto chunk_size = bcx->ne[0] / n_chunks;
-        auto *     b          = ggml_view_3d(ctx0, bcx, chunk_size, bcx->ne[1], bcx->ne[2], bcx->nb[1], bcx->nb[2],
-                                             0 * chunk_size * ggml_element_size(bcx));
-        auto *     c          = ggml_view_3d(ctx0, bcx, chunk_size, bcx->ne[1], bcx->ne[2], bcx->nb[1], bcx->nb[2],
-                                             1 * chunk_size * ggml_element_size(bcx));
-        auto *     x          = ggml_view_3d(ctx0, bcx, chunk_size, bcx->ne[1], bcx->ne[2], bcx->nb[1], bcx->nb[2],
-                                             2 * chunk_size * ggml_element_size(bcx));
-
-        auto * bx = ggml_transpose(ctx0, ggml_mul(ctx0, b, x));
-
-        // read conv state
-        auto * conv_state = mctx_cur->get_r_l(il);
-        auto * conv_rs    = build_rs(inp_recr, conv_state, hparams.n_embd_r(), n_seqs);
-        auto * conv       = ggml_reshape_3d(ctx0, conv_rs, d_conv, hparams.n_embd, n_seqs);
-
-        // causal prepends the state, non-causal pads symmetrically for a centered window
-        if (hparams.causal_attn) {
-            bx = ggml_concat(ctx0, conv, bx, 0);
-        } else {
-            const int64_t pad = (hparams.n_shortconv_l_cache - 1) / 2;
-            auto * left = ggml_cont(ctx0,
-                ggml_view_3d(ctx0, conv, pad, hparams.n_embd, n_seqs, conv->nb[1], conv->nb[2], (d_conv - pad) * conv->nb[0]));
-            bx = ggml_pad_ext(ctx0, ggml_concat(ctx0, left, bx, 0), 0, pad, 0, 0, 0, 0, 0, 0);
-        }
-        GGML_ASSERT(bx->ne[0] > conv->ne[0]);
-
-        // write conv states: slot 0 = the final state, slot s = the state s tokens back (partial rollback)
-        const int64_t K         = hparams.causal_attn && cparams.n_rs_seq > 0 ? (int64_t) cparams.n_rs_seq + 1 : 1;
-        const int64_t n_written = std::min<int64_t>(n_seq_tokens, K);
-        const auto    mem_size  = mctx_cur->get_size();
-        const size_t  row_size  = ggml_row_size(conv_state->type, (int64_t) d_conv * n_embd);
-
-        for (int64_t slot = 0; slot < n_written; ++slot) {
-            auto * conv_snap = ggml_view_3d(ctx0, bx, d_conv, bx->ne[1], bx->ne[2], bx->nb[1], bx->nb[2],
-                                            (bx->ne[0] - d_conv - slot) * ggml_element_size(bx));
-            ggml_build_forward_expand(gf, ggml_cpy(ctx0, conv_snap,
-                                                   ggml_view_2d(ctx0, conv_state, (int64_t) d_conv * n_embd, n_seqs,
-                                                                conv_state->nb[1],
-                                                                ((size_t) slot * mem_size + kv_head) * row_size)));
-        }
-
-        auto * conv_kernel = model.layers[il].shortconv.conv;
-        auto * conv_out    = ggml_ssm_conv(ctx0, bx, conv_kernel);
-        cb(conv_out, "model.layers.{}.conv.conv", il);
-
-        auto * y = ggml_mul(ctx0, c, conv_out);
-        y        = build_lora_mm(model.layers[il].shortconv.out_proj, y);
-        cb(y, "model.layers.{}.conv.out_proj", il);
-        // {n_embd, n_seq_tokens, n_seqs} => {n_embd, n_tokens}
-        y = ggml_reshape_2d(ctx0, y, y->ne[0], n_seq_tokens * n_seqs);
-
-        return y;
-    };
-
     // actual graph construction starts here
     ggml_tensor * cur = build_inp_embd(model.tok_embd);
     cb(cur, "model.embed_tokens", -1);
@@ -308,8 +208,12 @@ llama_model_lfm2::graph<iswa>::graph(const llama_model & model, const llm_graph_
         cur             = build_norm(cur, model.layers[il].attn_norm, NULL, LLM_NORM_RMS, il);
         cb(cur, "model.layers.{}.operator_norm", il);

-        cur = hparams.is_recr(il) ? build_shortconv_block(cur, inp_hybrid->get_recr(), il) :
-                                    build_attn_block(cur, inp_pos, inp_hybrid->get_attn(), il);
+        if (hparams.is_recr(il)) {
+            const auto * mctx_recr = static_cast<const mem_hybrid_ctx *>(mctx)->get_recr();
+            cur = build_lfm_shortconv(model, mctx_recr, inp_hybrid->get_recr(), cur, il);
+        } else {
+            cur = build_attn_block(cur, inp_pos, inp_hybrid->get_attn(), il);
+        }

         if (il == n_layer - 1 && inp_out_ids) {
             cur      = ggml_get_rows(ctx0, cur, inp_out_ids);
@@ -322,7 +226,7 @@ llama_model_lfm2::graph<iswa>::graph(const llama_model & model, const llm_graph_
         cb(ffn_norm_out, "model.layers.{}.ffn_norm", il);

         ggml_tensor * ffn_out =
-            is_moe_layer ? build_moe_feed_forward(ffn_norm_out, il) : build_dense_feed_forward(ffn_norm_out, il);
+            is_moe_layer ? build_lfm_moe_ffn(model, ffn_norm_out, il) : build_lfm_dense_ffn(model, ffn_norm_out, il);
         cb(ffn_norm_out, "model.layers.{}.ffn_out", il);

         cur = ggml_add(ctx0, cur, ffn_out);
diff --git a/src/models/models.h b/src/models/models.h
index e6cf9d213..9aa450dea 100644
--- a/src/models/models.h
+++ b/src/models/models.h
@@ -100,6 +100,26 @@ struct llm_build_delta_net_base : public llm_graph_context {
             int                  il);
 };

+struct llm_build_lfm_base : public llm_graph_context {
+    llm_build_lfm_base(const llm_graph_params & params);
+
+    virtual ~llm_build_lfm_base() = default;
+
+    ggml_tensor * build_lfm_shortconv(const llama_model & model,
+                                      const llama_memory_recurrent_context * mctx_recr,
+                                      llm_graph_input_rs * inp_recr,
+                                      ggml_tensor * cur,
+                                      int il);
+
+    ggml_tensor * build_lfm_dense_ffn(const llama_model & model,
+                                      ggml_tensor * cur,
+                                      int il);
+
+    ggml_tensor * build_lfm_moe_ffn(const llama_model & model,
+                                    ggml_tensor * cur,
+                                    int il);
+};
+
 struct llm_build_rwkv6_base : public llm_graph_context {
     const llama_model & model;

@@ -2264,7 +2284,7 @@ struct llama_model_lfm2 : public llama_model_base {
     void load_arch_tensors(llama_model_loader & ml) override;

     template <bool iswa>
-    struct graph : public llm_graph_context {
+    struct graph : public llm_build_lfm_base {
         graph(const llama_model & model, const llm_graph_params & params);
     };