Function ggml_new_graph_custom

subprojects/llama.cpp/ggml/src/ggml.c:6966–7008

}

struct ggml_cgraph * ggml_new_graph_custom(struct ggml_context * ctx, size_t size, bool grads) {
    const size_t obj_size = ggml_graph_nbytes(size, grads);
    struct ggml_object * obj = ggml_new_object(ctx, GGML_OBJECT_TYPE_GRAPH, obj_size);
    struct ggml_cgraph * cgraph = (struct ggml_cgraph *) ((char *) ctx->mem_buffer + obj->offs);

    // the size of the hash table is doubled since it needs to hold both nodes and leafs
    size_t hash_size = ggml_hash_size(size * 2);

    void * p = cgraph + 1;

    struct ggml_tensor ** nodes_ptr      =         incr_ptr_aligned(&p, size      * sizeof(struct ggml_tensor *), sizeof(struct ggml_tensor *));
    struct ggml_tensor ** leafs_ptr      =         incr_ptr_aligned(&p, size      * sizeof(struct ggml_tensor *), sizeof(struct ggml_tensor *));
    int32_t             * use_counts_ptr =         incr_ptr_aligned(&p, hash_size * sizeof(int32_t), sizeof(int32_t));
    struct ggml_tensor ** hash_keys_ptr  =         incr_ptr_aligned(&p, hash_size * sizeof(struct ggml_tensor *), sizeof(struct ggml_tensor *));
    struct ggml_tensor ** grads_ptr      = grads ? incr_ptr_aligned(&p, hash_size * sizeof(struct ggml_tensor *), sizeof(struct ggml_tensor *)) : NULL;
    struct ggml_tensor ** grad_accs_ptr  = grads ? incr_ptr_aligned(&p, hash_size * sizeof(struct ggml_tensor *), sizeof(struct ggml_tensor *)) : NULL;

    ggml_bitset_t * hash_used = incr_ptr_aligned(&p, ggml_bitset_size(hash_size) * sizeof(ggml_bitset_t), sizeof(ggml_bitset_t));

    // check that we allocated the correct amount of memory
    assert(obj_size == (size_t)((char *)p - (char *)cgraph));

    *cgraph = (struct ggml_cgraph) {
        /*.size         =*/ size,
        /*.n_nodes      =*/ 0,
        /*.n_leafs      =*/ 0,
        /*.nodes        =*/ nodes_ptr,
        /*.grads        =*/ grads_ptr,
        /*.grad_accs    =*/ grad_accs_ptr,
        /*.leafs        =*/ leafs_ptr,
        /*.use_counts   =*/ use_counts_ptr,
        /*.hash_table   =*/ { hash_size, hash_used, hash_keys_ptr },
        /*.order        =*/ GGML_CGRAPH_EVAL_ORDER_LEFT_TO_RIGHT,
    };

    ggml_hash_set_reset(&cgraph->visited_hash_set);
    if (grads) {
        memset(cgraph->grads,     0, hash_size*sizeof(struct ggml_tensor *));
        memset(cgraph->grad_accs, 0, hash_size*sizeof(struct ggml_tensor *));
    }

    return cgraph;
}

struct ggml_cgraph * ggml_new_graph(struct ggml_context * ctx) {
    return ggml_new_graph_custom(ctx, GGML_DEFAULT_GRAPH_SIZE, false);