Function ggml_gallocr_allocate_node

external/ggml/src/ggml-alloc.c:622–688

}

static void ggml_gallocr_allocate_node(ggml_gallocr_t galloc, struct ggml_tensor * node, int buffer_id) {
    GGML_ASSERT(buffer_id >= 0);
    struct hash_node * hn = ggml_gallocr_hash_get(galloc, node);

    if (!ggml_gallocr_is_allocated(galloc, node) && !ggml_impl_is_view(node)) {
        hn->allocated = true;
        assert(hn->addr.offset == 0);

        // try to reuse a parent's buffer (inplace)
        if (ggml_op_can_inplace(node->op)) {
            for (int i = 0; i < GGML_MAX_SRC; i++) {
                struct ggml_tensor * parent = node->src[i];
                if (parent == NULL) {
                    continue;
                }

                // if the node's data is external, then we cannot re-use it
                if (!ggml_gallocr_is_own(galloc, parent)) {
                    AT_PRINTF("not reusing parent %s for %s as %p is external\n", parent->name, node->name, parent->data);
                    continue;
                }

                // outputs cannot be reused
                if (parent->flags & GGML_TENSOR_FLAG_OUTPUT || (parent->view_src != NULL && parent->view_src->flags & GGML_TENSOR_FLAG_OUTPUT)) {
                    AT_PRINTF("not reusing parent %s for %s as it is an output\n", parent->name, node->name);
                    continue;
                }

                if (!ggml_are_same_layout(node, parent)) {
                    AT_PRINTF("not reusing parent %s for %s as layouts are different\n", parent->name, node->name);
                    continue;
                }

                struct hash_node * p_hn = ggml_gallocr_hash_get(galloc, parent);
                if (p_hn->n_children == 1 && p_hn->n_views == 0) {
                    if (ggml_impl_is_view(parent)) {
                        struct ggml_tensor * view_src = parent->view_src;
                        struct hash_node * view_src_hn = ggml_gallocr_hash_get(galloc, view_src);
                        if (view_src_hn->n_views == 1 && view_src_hn->n_children == 0 && view_src->data == parent->data) {
                            AT_PRINTF("reusing view parent %s (%s) for %s\n", parent->name, view_src->name, node->name);
                            assert(view_src_hn->addr.chunk == p_hn->addr.chunk && view_src_hn->addr.offset == p_hn->addr.offset);
                            hn->buffer_id = p_hn->buffer_id;
                            hn->addr = p_hn->addr;
                            p_hn->allocated = false; // avoid freeing the parent
                            view_src_hn->allocated = false;
                            ggml_gallocr_free_extra_space(galloc, node, view_src);
                            return;
                        }
                    } else {
                        AT_PRINTF("reusing parent %s for %s\n", parent->name, node->name);
                        hn->buffer_id = p_hn->buffer_id;
                        hn->addr = p_hn->addr;
                        p_hn->allocated = false; // avoid freeing the parent
                        ggml_gallocr_free_extra_space(galloc, node, parent);
                        return;
                    }
                }
            }