From 00812008129bdab48d328775b09332af12118867 Mon Sep 17 00:00:00 2001 From: Jacques Lucke Date: Fri, 20 Aug 2021 13:14:39 +0200 Subject: Functions: remove multi-function network The multi-function network system was able to compose multiple multi-functions into a new one and to evaluate that efficiently. This functionality was heavily used by the particle nodes prototype a year ago. However, since then we only used multi-functions without the need to compose them in geometry nodes. The upcoming "fields" in geometry nodes will need a way to compose multi-functions again. Unfortunately, the code removed in this commit was not ideal for this different kind of function composition. I've been working on an alternative that will be added separately when it becomes needed. I've had to update all the function nodes, because their interface depended on the multi-function network data structure a bit. The actual multi-function implementations are still the same though. --- .../intern/multi_function_network_optimization.cc | 501 --------------------- 1 file changed, 501 deletions(-) delete mode 100644 source/blender/functions/intern/multi_function_network_optimization.cc (limited to 'source/blender/functions/intern/multi_function_network_optimization.cc') diff --git a/source/blender/functions/intern/multi_function_network_optimization.cc b/source/blender/functions/intern/multi_function_network_optimization.cc deleted file mode 100644 index 75c3583c5e5..00000000000 --- a/source/blender/functions/intern/multi_function_network_optimization.cc +++ /dev/null @@ -1,501 +0,0 @@ -/* - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version 2 - * of the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software Foundation, - * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. - */ - -/** \file - * \ingroup fn - */ - -/* Used to check if two multi-functions have the exact same type. */ -#include - -#include "FN_multi_function_builder.hh" -#include "FN_multi_function_network_evaluation.hh" -#include "FN_multi_function_network_optimization.hh" - -#include "BLI_disjoint_set.hh" -#include "BLI_ghash.h" -#include "BLI_map.hh" -#include "BLI_multi_value_map.hh" -#include "BLI_rand.h" -#include "BLI_stack.hh" - -namespace blender::fn::mf_network_optimization { - -/* -------------------------------------------------------------------- */ -/** \name Utility functions to find nodes in a network. - * \{ */ - -static bool set_tag_and_check_if_modified(bool &tag, bool new_value) -{ - if (tag != new_value) { - tag = new_value; - return true; - } - - return false; -} - -static Array mask_nodes_to_the_left(MFNetwork &network, Span nodes) -{ - Array is_to_the_left(network.node_id_amount(), false); - Stack nodes_to_check; - - for (MFNode *node : nodes) { - is_to_the_left[node->id()] = true; - nodes_to_check.push(node); - } - - while (!nodes_to_check.is_empty()) { - MFNode &node = *nodes_to_check.pop(); - - for (MFInputSocket *input_socket : node.inputs()) { - MFOutputSocket *origin = input_socket->origin(); - if (origin != nullptr) { - MFNode &origin_node = origin->node(); - if (set_tag_and_check_if_modified(is_to_the_left[origin_node.id()], true)) { - nodes_to_check.push(&origin_node); - } - } - } - } - - return is_to_the_left; -} - -static Array mask_nodes_to_the_right(MFNetwork &network, Span nodes) -{ - Array is_to_the_right(network.node_id_amount(), false); - Stack nodes_to_check; - - for (MFNode *node : nodes) { - is_to_the_right[node->id()] = true; - nodes_to_check.push(node); - } - - while (!nodes_to_check.is_empty()) { - MFNode &node = *nodes_to_check.pop(); - - for (MFOutputSocket *output_socket : node.outputs()) { - for (MFInputSocket *target_socket : output_socket->targets()) { - MFNode &target_node = target_socket->node(); - if (set_tag_and_check_if_modified(is_to_the_right[target_node.id()], true)) { - nodes_to_check.push(&target_node); - } - } - } - } - - return is_to_the_right; -} - -static Vector find_nodes_based_on_mask(MFNetwork &network, - Span id_mask, - bool mask_value) -{ - Vector nodes; - for (int id : id_mask.index_range()) { - if (id_mask[id] == mask_value) { - MFNode *node = network.node_or_null_by_id(id); - if (node != nullptr) { - nodes.append(node); - } - } - } - return nodes; -} - -/** \} */ - -/* -------------------------------------------------------------------- */ -/** \name Dead Node Removal - * \{ */ - -/** - * Unused nodes are all those nodes that no dummy node depends upon. - */ -void dead_node_removal(MFNetwork &network) -{ - Array node_is_used_mask = mask_nodes_to_the_left(network, - network.dummy_nodes().cast()); - Vector nodes_to_remove = find_nodes_based_on_mask(network, node_is_used_mask, false); - network.remove(nodes_to_remove); -} - -/** \} */ - -/* -------------------------------------------------------------------- */ -/** \name Constant Folding - * \{ */ - -static bool function_node_can_be_constant(MFFunctionNode *node) -{ - if (node->has_unlinked_inputs()) { - return false; - } - if (node->function().depends_on_context()) { - return false; - } - return true; -} - -static Vector find_non_constant_nodes(MFNetwork &network) -{ - Vector non_constant_nodes; - non_constant_nodes.extend(network.dummy_nodes().cast()); - - for (MFFunctionNode *node : network.function_nodes()) { - if (!function_node_can_be_constant(node)) { - non_constant_nodes.append(node); - } - } - return non_constant_nodes; -} - -static bool output_has_non_constant_target_node(MFOutputSocket *output_socket, - Span is_not_constant_mask) -{ - for (MFInputSocket *target_socket : output_socket->targets()) { - MFNode &target_node = target_socket->node(); - bool target_is_not_constant = is_not_constant_mask[target_node.id()]; - if (target_is_not_constant) { - return true; - } - } - return false; -} - -static MFInputSocket *try_find_dummy_target_socket(MFOutputSocket *output_socket) -{ - for (MFInputSocket *target_socket : output_socket->targets()) { - if (target_socket->node().is_dummy()) { - return target_socket; - } - } - return nullptr; -} - -static Vector find_constant_inputs_to_fold( - MFNetwork &network, Vector &r_temporary_nodes) -{ - Vector non_constant_nodes = find_non_constant_nodes(network); - Array is_not_constant_mask = mask_nodes_to_the_right(network, non_constant_nodes); - Vector constant_nodes = find_nodes_based_on_mask(network, is_not_constant_mask, false); - - Vector sockets_to_compute; - for (MFNode *node : constant_nodes) { - if (node->inputs().size() == 0) { - continue; - } - - for (MFOutputSocket *output_socket : node->outputs()) { - MFDataType data_type = output_socket->data_type(); - if (output_has_non_constant_target_node(output_socket, is_not_constant_mask)) { - MFInputSocket *dummy_target = try_find_dummy_target_socket(output_socket); - if (dummy_target == nullptr) { - dummy_target = &network.add_output("Dummy", data_type); - network.add_link(*output_socket, *dummy_target); - r_temporary_nodes.append(&dummy_target->node().as_dummy()); - } - - sockets_to_compute.append(dummy_target); - } - } - } - return sockets_to_compute; -} - -static void prepare_params_for_constant_folding(const MultiFunction &network_fn, - MFParamsBuilder ¶ms, - ResourceScope &scope) -{ - for (int param_index : network_fn.param_indices()) { - MFParamType param_type = network_fn.param_type(param_index); - MFDataType data_type = param_type.data_type(); - - switch (data_type.category()) { - case MFDataType::Single: { - /* Allocates memory for a single constant folded value. */ - const CPPType &cpp_type = data_type.single_type(); - void *buffer = scope.linear_allocator().allocate(cpp_type.size(), cpp_type.alignment()); - GMutableSpan array{cpp_type, buffer, 1}; - params.add_uninitialized_single_output(array); - break; - } - case MFDataType::Vector: { - /* Allocates memory for a constant folded vector. */ - const CPPType &cpp_type = data_type.vector_base_type(); - GVectorArray &vector_array = scope.construct(AT, cpp_type, 1); - params.add_vector_output(vector_array); - break; - } - } - } -} - -static Array add_constant_folded_sockets(const MultiFunction &network_fn, - MFParamsBuilder ¶ms, - ResourceScope &scope, - MFNetwork &network) -{ - Array folded_sockets{network_fn.param_indices().size(), nullptr}; - - for (int param_index : network_fn.param_indices()) { - MFParamType param_type = network_fn.param_type(param_index); - MFDataType data_type = param_type.data_type(); - - const MultiFunction *constant_fn = nullptr; - - switch (data_type.category()) { - case MFDataType::Single: { - const CPPType &cpp_type = data_type.single_type(); - GMutableSpan array = params.computed_array(param_index); - void *buffer = array.data(); - scope.add(buffer, array.type().destruct_fn(), AT); - - constant_fn = &scope.construct(AT, cpp_type, buffer); - break; - } - case MFDataType::Vector: { - GVectorArray &vector_array = params.computed_vector_array(param_index); - GSpan array = vector_array[0]; - constant_fn = &scope.construct(AT, array); - break; - } - } - - MFFunctionNode &folded_node = network.add_function(*constant_fn); - folded_sockets[param_index] = &folded_node.output(0); - } - return folded_sockets; -} - -static Array compute_constant_sockets_and_add_folded_nodes( - MFNetwork &network, Span sockets_to_compute, ResourceScope &scope) -{ - MFNetworkEvaluator network_fn{{}, sockets_to_compute}; - - MFContextBuilder context; - MFParamsBuilder params{network_fn, 1}; - prepare_params_for_constant_folding(network_fn, params, scope); - network_fn.call({0}, params, context); - return add_constant_folded_sockets(network_fn, params, scope, network); -} - -class MyClass { - MFDummyNode node; -}; - -/** - * Find function nodes that always output the same value and replace those with constant nodes. - */ -void constant_folding(MFNetwork &network, ResourceScope &scope) -{ - Vector temporary_nodes; - Vector inputs_to_fold = find_constant_inputs_to_fold(network, temporary_nodes); - if (inputs_to_fold.size() == 0) { - return; - } - - Array folded_sockets = compute_constant_sockets_and_add_folded_nodes( - network, inputs_to_fold, scope); - - for (int i : inputs_to_fold.index_range()) { - MFOutputSocket &original_socket = *inputs_to_fold[i]->origin(); - network.relink(original_socket, *folded_sockets[i]); - } - - network.remove(temporary_nodes.as_span().cast()); -} - -/** \} */ - -/* -------------------------------------------------------------------- */ -/** \name Common Sub-network Elimination - * \{ */ - -static uint64_t compute_node_hash(MFFunctionNode &node, RNG *rng, Span node_hashes) -{ - if (node.function().depends_on_context()) { - return BLI_rng_get_uint(rng); - } - if (node.has_unlinked_inputs()) { - return BLI_rng_get_uint(rng); - } - - uint64_t combined_inputs_hash = 394659347u; - for (MFInputSocket *input_socket : node.inputs()) { - MFOutputSocket *origin_socket = input_socket->origin(); - uint64_t input_hash = BLI_ghashutil_combine_hash(node_hashes[origin_socket->node().id()], - origin_socket->index()); - combined_inputs_hash = BLI_ghashutil_combine_hash(combined_inputs_hash, input_hash); - } - - uint64_t function_hash = node.function().hash(); - uint64_t node_hash = BLI_ghashutil_combine_hash(combined_inputs_hash, function_hash); - return node_hash; -} - -/** - * Produces a hash for every node. Two nodes with the same hash should have a high probability of - * outputting the same values. - */ -static Array compute_node_hashes(MFNetwork &network) -{ - RNG *rng = BLI_rng_new(0); - Array node_hashes(network.node_id_amount()); - Array node_is_hashed(network.node_id_amount(), false); - - /* No dummy nodes are not assumed to output the same values. */ - for (MFDummyNode *node : network.dummy_nodes()) { - uint64_t node_hash = BLI_rng_get_uint(rng); - node_hashes[node->id()] = node_hash; - node_is_hashed[node->id()] = true; - } - - Stack nodes_to_check; - nodes_to_check.push_multiple(network.function_nodes()); - - while (!nodes_to_check.is_empty()) { - MFFunctionNode &node = *nodes_to_check.peek(); - if (node_is_hashed[node.id()]) { - nodes_to_check.pop(); - continue; - } - - /* Make sure that origin nodes are hashed first. */ - bool all_dependencies_ready = true; - for (MFInputSocket *input_socket : node.inputs()) { - MFOutputSocket *origin_socket = input_socket->origin(); - if (origin_socket != nullptr) { - MFNode &origin_node = origin_socket->node(); - if (!node_is_hashed[origin_node.id()]) { - all_dependencies_ready = false; - nodes_to_check.push(&origin_node.as_function()); - } - } - } - if (!all_dependencies_ready) { - continue; - } - - uint64_t node_hash = compute_node_hash(node, rng, node_hashes); - node_hashes[node.id()] = node_hash; - node_is_hashed[node.id()] = true; - nodes_to_check.pop(); - } - - BLI_rng_free(rng); - return node_hashes; -} - -static MultiValueMap group_nodes_by_hash(MFNetwork &network, - Span node_hashes) -{ - MultiValueMap nodes_by_hash; - for (int id : IndexRange(network.node_id_amount())) { - MFNode *node = network.node_or_null_by_id(id); - if (node != nullptr) { - uint64_t node_hash = node_hashes[id]; - nodes_by_hash.add(node_hash, node); - } - } - return nodes_by_hash; -} - -static bool functions_are_equal(const MultiFunction &a, const MultiFunction &b) -{ - if (&a == &b) { - return true; - } - if (typeid(a) == typeid(b)) { - return a.equals(b); - } - return false; -} - -static bool nodes_output_same_values(DisjointSet &cache, const MFNode &a, const MFNode &b) -{ - if (cache.in_same_set(a.id(), b.id())) { - return true; - } - - if (a.is_dummy() || b.is_dummy()) { - return false; - } - if (!functions_are_equal(a.as_function().function(), b.as_function().function())) { - return false; - } - for (int i : a.inputs().index_range()) { - const MFOutputSocket *origin_a = a.input(i).origin(); - const MFOutputSocket *origin_b = b.input(i).origin(); - if (origin_a == nullptr || origin_b == nullptr) { - return false; - } - if (!nodes_output_same_values(cache, origin_a->node(), origin_b->node())) { - return false; - } - } - - cache.join(a.id(), b.id()); - return true; -} - -static void relink_duplicate_nodes(MFNetwork &network, - MultiValueMap &nodes_by_hash) -{ - DisjointSet same_node_cache{network.node_id_amount()}; - - for (Span nodes_with_same_hash : nodes_by_hash.values()) { - if (nodes_with_same_hash.size() <= 1) { - continue; - } - - Vector nodes_to_check = nodes_with_same_hash; - while (nodes_to_check.size() >= 2) { - Vector remaining_nodes; - - MFNode &deduplicated_node = *nodes_to_check[0]; - for (MFNode *node : nodes_to_check.as_span().drop_front(1)) { - /* This is true with fairly high probability, but hash collisions can happen. So we have to - * check if the node actually output the same values. */ - if (nodes_output_same_values(same_node_cache, deduplicated_node, *node)) { - for (int i : deduplicated_node.outputs().index_range()) { - network.relink(node->output(i), deduplicated_node.output(i)); - } - } - else { - remaining_nodes.append(node); - } - } - nodes_to_check = std::move(remaining_nodes); - } - } -} - -/** - * Tries to detect duplicate sub-networks and eliminates them. This can help quite a lot when node - * groups were used to create the network. - */ -void common_subnetwork_elimination(MFNetwork &network) -{ - Array node_hashes = compute_node_hashes(network); - MultiValueMap nodes_by_hash = group_nodes_by_hash(network, node_hashes); - relink_duplicate_nodes(network, nodes_by_hash); -} - -/** \} */ - -} // namespace blender::fn::mf_network_optimization -- cgit v1.2.3