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-rw-r--r--thirdparty/harfbuzz/src/graph/coverage-graph.hh80
-rw-r--r--thirdparty/harfbuzz/src/graph/graph.hh1046
-rw-r--r--thirdparty/harfbuzz/src/graph/gsubgpos-context.cc71
-rw-r--r--thirdparty/harfbuzz/src/graph/gsubgpos-context.hh67
-rw-r--r--thirdparty/harfbuzz/src/graph/gsubgpos-graph.hh351
-rw-r--r--thirdparty/harfbuzz/src/graph/pairpos-graph.hh299
-rw-r--r--thirdparty/harfbuzz/src/graph/serialize.hh249
7 files changed, 2163 insertions, 0 deletions
diff --git a/thirdparty/harfbuzz/src/graph/coverage-graph.hh b/thirdparty/harfbuzz/src/graph/coverage-graph.hh
new file mode 100644
index 0000000000..1d9fd0eb5b
--- /dev/null
+++ b/thirdparty/harfbuzz/src/graph/coverage-graph.hh
@@ -0,0 +1,80 @@
+/*
+ * Copyright © 2022 Google, Inc.
+ *
+ * This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Garret Rieger
+ */
+
+#include "graph.hh"
+#include "../OT/Layout/Common/Coverage.hh"
+
+#ifndef GRAPH_COVERAGE_GRAPH_HH
+#define GRAPH_COVERAGE_GRAPH_HH
+
+namespace graph {
+
+struct CoverageFormat1 : public OT::Layout::Common::CoverageFormat1_3<SmallTypes>
+{
+ bool sanitize (graph_t::vertex_t& vertex) const
+ {
+ int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+ constexpr unsigned min_size = OT::Layout::Common::CoverageFormat1_3<SmallTypes>::min_size;
+ if (vertex_len < min_size) return false;
+ return vertex_len >= min_size + glyphArray.get_size () - glyphArray.len.get_size ();
+ }
+};
+
+struct CoverageFormat2 : public OT::Layout::Common::CoverageFormat2_4<SmallTypes>
+{
+ bool sanitize (graph_t::vertex_t& vertex) const
+ {
+ int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+ constexpr unsigned min_size = OT::Layout::Common::CoverageFormat2_4<SmallTypes>::min_size;
+ if (vertex_len < min_size) return false;
+ return vertex_len >= min_size + rangeRecord.get_size () - rangeRecord.len.get_size ();
+ }
+};
+
+struct Coverage : public OT::Layout::Common::Coverage
+{
+ bool sanitize (graph_t::vertex_t& vertex) const
+ {
+ int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+ if (vertex_len < OT::Layout::Common::Coverage::min_size) return false;
+ switch (u.format)
+ {
+ case 1: return ((CoverageFormat1*)this)->sanitize (vertex);
+ case 2: return ((CoverageFormat2*)this)->sanitize (vertex);
+#ifndef HB_NO_BORING_EXPANSION
+ // Not currently supported
+ case 3:
+ case 4:
+#endif
+ default: return false;
+ }
+ }
+};
+
+
+}
+
+#endif // GRAPH_COVERAGE_GRAPH_HH
diff --git a/thirdparty/harfbuzz/src/graph/graph.hh b/thirdparty/harfbuzz/src/graph/graph.hh
new file mode 100644
index 0000000000..b3aef558a2
--- /dev/null
+++ b/thirdparty/harfbuzz/src/graph/graph.hh
@@ -0,0 +1,1046 @@
+/*
+ * Copyright © 2022 Google, Inc.
+ *
+ * This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Garret Rieger
+ */
+
+#include "../hb-set.hh"
+#include "../hb-priority-queue.hh"
+#include "../hb-serialize.hh"
+
+#ifndef GRAPH_GRAPH_HH
+#define GRAPH_GRAPH_HH
+
+namespace graph {
+
+/**
+ * Represents a serialized table in the form of a graph.
+ * Provides methods for modifying and reordering the graph.
+ */
+struct graph_t
+{
+ struct vertex_t
+ {
+ hb_serialize_context_t::object_t obj;
+ int64_t distance = 0 ;
+ int64_t space = 0 ;
+ hb_vector_t<unsigned> parents;
+ unsigned start = 0;
+ unsigned end = 0;
+ unsigned priority = 0;
+
+ friend void swap (vertex_t& a, vertex_t& b)
+ {
+ hb_swap (a.obj, b.obj);
+ hb_swap (a.distance, b.distance);
+ hb_swap (a.space, b.space);
+ hb_swap (a.parents, b.parents);
+ hb_swap (a.start, b.start);
+ hb_swap (a.end, b.end);
+ hb_swap (a.priority, b.priority);
+ }
+
+ bool is_shared () const
+ {
+ return parents.length > 1;
+ }
+
+ unsigned incoming_edges () const
+ {
+ return parents.length;
+ }
+
+ void remove_parent (unsigned parent_index)
+ {
+ for (unsigned i = 0; i < parents.length; i++)
+ {
+ if (parents[i] != parent_index) continue;
+ parents.remove (i);
+ break;
+ }
+ }
+
+ void remove_real_link (unsigned child_index, const void* offset)
+ {
+ for (unsigned i = 0; i < obj.real_links.length; i++)
+ {
+ auto& link = obj.real_links[i];
+ if (link.objidx != child_index)
+ continue;
+
+ if ((obj.head + link.position) != offset)
+ continue;
+
+ obj.real_links.remove (i);
+ return;
+ }
+ }
+
+ void remap_parents (const hb_vector_t<unsigned>& id_map)
+ {
+ for (unsigned i = 0; i < parents.length; i++)
+ parents[i] = id_map[parents[i]];
+ }
+
+ void remap_parent (unsigned old_index, unsigned new_index)
+ {
+ for (unsigned i = 0; i < parents.length; i++)
+ {
+ if (parents[i] == old_index)
+ parents[i] = new_index;
+ }
+ }
+
+ bool is_leaf () const
+ {
+ return !obj.real_links.length && !obj.virtual_links.length;
+ }
+
+ bool raise_priority ()
+ {
+ if (has_max_priority ()) return false;
+ priority++;
+ return true;
+ }
+
+ bool has_max_priority () const {
+ return priority >= 3;
+ }
+
+ size_t table_size () const {
+ return obj.tail - obj.head;
+ }
+
+ int64_t modified_distance (unsigned order) const
+ {
+ // TODO(garretrieger): once priority is high enough, should try
+ // setting distance = 0 which will force to sort immediately after
+ // it's parent where possible.
+
+ int64_t modified_distance =
+ hb_min (hb_max(distance + distance_modifier (), 0), 0x7FFFFFFFFFF);
+ if (has_max_priority ()) {
+ modified_distance = 0;
+ }
+ return (modified_distance << 18) | (0x003FFFF & order);
+ }
+
+ int64_t distance_modifier () const
+ {
+ if (!priority) return 0;
+ int64_t table_size = obj.tail - obj.head;
+
+ if (priority == 1)
+ return -table_size / 2;
+
+ return -table_size;
+ }
+ };
+
+ /*
+ * A topological sorting of an object graph. Ordered
+ * in reverse serialization order (first object in the
+ * serialization is at the end of the list). This matches
+ * the 'packed' object stack used internally in the
+ * serializer
+ */
+ template<typename T>
+ graph_t (const T& objects)
+ : parents_invalid (true),
+ distance_invalid (true),
+ positions_invalid (true),
+ successful (true)
+ {
+ num_roots_for_space_.push (1);
+ bool removed_nil = false;
+ vertices_.alloc (objects.length);
+ vertices_scratch_.alloc (objects.length);
+ for (unsigned i = 0; i < objects.length; i++)
+ {
+ // TODO(grieger): check all links point to valid objects.
+
+ // If this graph came from a serialization buffer object 0 is the
+ // nil object. We don't need it for our purposes here so drop it.
+ if (i == 0 && !objects[i])
+ {
+ removed_nil = true;
+ continue;
+ }
+
+ vertex_t* v = vertices_.push ();
+ if (check_success (!vertices_.in_error ()))
+ v->obj = *objects[i];
+ if (!removed_nil) continue;
+ // Fix indices to account for removed nil object.
+ for (auto& l : v->obj.all_links_writer ()) {
+ l.objidx--;
+ }
+ }
+ }
+
+ ~graph_t ()
+ {
+ vertices_.fini ();
+ }
+
+ bool in_error () const
+ {
+ return !successful ||
+ vertices_.in_error () ||
+ num_roots_for_space_.in_error ();
+ }
+
+ const vertex_t& root () const
+ {
+ return vertices_[root_idx ()];
+ }
+
+ unsigned root_idx () const
+ {
+ // Object graphs are in reverse order, the first object is at the end
+ // of the vector. Since the graph is topologically sorted it's safe to
+ // assume the first object has no incoming edges.
+ return vertices_.length - 1;
+ }
+
+ const hb_serialize_context_t::object_t& object (unsigned i) const
+ {
+ return vertices_[i].obj;
+ }
+
+ /*
+ * Generates a new topological sorting of graph ordered by the shortest
+ * distance to each node if positions are marked as invalid.
+ */
+ void sort_shortest_distance_if_needed ()
+ {
+ if (!positions_invalid) return;
+ sort_shortest_distance ();
+ }
+
+
+ /*
+ * Generates a new topological sorting of graph ordered by the shortest
+ * distance to each node.
+ */
+ void sort_shortest_distance ()
+ {
+ positions_invalid = true;
+
+ if (vertices_.length <= 1) {
+ // Graph of 1 or less doesn't need sorting.
+ return;
+ }
+
+ update_distances ();
+
+ hb_priority_queue_t queue;
+ hb_vector_t<vertex_t> &sorted_graph = vertices_scratch_;
+ if (unlikely (!check_success (sorted_graph.resize (vertices_.length)))) return;
+ hb_vector_t<unsigned> id_map;
+ if (unlikely (!check_success (id_map.resize (vertices_.length)))) return;
+
+ hb_vector_t<unsigned> removed_edges;
+ if (unlikely (!check_success (removed_edges.resize (vertices_.length)))) return;
+ update_parents ();
+
+ queue.insert (root ().modified_distance (0), root_idx ());
+ int new_id = root_idx ();
+ unsigned order = 1;
+ while (!queue.in_error () && !queue.is_empty ())
+ {
+ unsigned next_id = queue.pop_minimum().second;
+
+ hb_swap (sorted_graph[new_id], vertices_[next_id]);
+ const vertex_t& next = sorted_graph[new_id];
+
+ id_map[next_id] = new_id--;
+
+ for (const auto& link : next.obj.all_links ()) {
+ removed_edges[link.objidx]++;
+ if (!(vertices_[link.objidx].incoming_edges () - removed_edges[link.objidx]))
+ // Add the order that the links were encountered to the priority.
+ // This ensures that ties between priorities objects are broken in a consistent
+ // way. More specifically this is set up so that if a set of objects have the same
+ // distance they'll be added to the topological order in the order that they are
+ // referenced from the parent object.
+ queue.insert (vertices_[link.objidx].modified_distance (order++),
+ link.objidx);
+ }
+ }
+
+ check_success (!queue.in_error ());
+ check_success (!sorted_graph.in_error ());
+
+ remap_all_obj_indices (id_map, &sorted_graph);
+ hb_swap (vertices_, sorted_graph);
+
+ if (!check_success (new_id == -1))
+ print_orphaned_nodes ();
+ }
+
+ /*
+ * Finds the set of nodes (placed into roots) that should be assigned unique spaces.
+ * More specifically this looks for the top most 24 bit or 32 bit links in the graph.
+ * Some special casing is done that is specific to the layout of GSUB/GPOS tables.
+ */
+ void find_space_roots (hb_set_t& visited, hb_set_t& roots)
+ {
+ int root_index = (int) root_idx ();
+ for (int i = root_index; i >= 0; i--)
+ {
+ if (visited.has (i)) continue;
+
+ // Only real links can form 32 bit spaces
+ for (auto& l : vertices_[i].obj.real_links)
+ {
+ if (l.is_signed || l.width < 3)
+ continue;
+
+ if (i == root_index && l.width == 3)
+ // Ignore 24bit links from the root node, this skips past the single 24bit
+ // pointer to the lookup list.
+ continue;
+
+ if (l.width == 3)
+ {
+ // A 24bit offset forms a root, unless there is 32bit offsets somewhere
+ // in it's subgraph, then those become the roots instead. This is to make sure
+ // that extension subtables beneath a 24bit lookup become the spaces instead
+ // of the offset to the lookup.
+ hb_set_t sub_roots;
+ find_32bit_roots (l.objidx, sub_roots);
+ if (sub_roots) {
+ for (unsigned sub_root_idx : sub_roots) {
+ roots.add (sub_root_idx);
+ find_subgraph (sub_root_idx, visited);
+ }
+ continue;
+ }
+ }
+
+ roots.add (l.objidx);
+ find_subgraph (l.objidx, visited);
+ }
+ }
+ }
+
+ unsigned index_for_offset(unsigned node_idx, const void* offset) const
+ {
+ const auto& node = object (node_idx);
+ if (offset < node.head || offset >= node.tail) return -1;
+
+ for (const auto& link : node.real_links)
+ {
+ if (offset != node.head + link.position)
+ continue;
+ return link.objidx;
+ }
+
+ return -1;
+ }
+
+
+ /*
+ * Assign unique space numbers to each connected subgraph of 24 bit and/or 32 bit offset(s).
+ * Currently, this is implemented specifically tailored to the structure of a GPOS/GSUB
+ * (including with 24bit offsets) table.
+ */
+ bool assign_spaces ()
+ {
+ update_parents ();
+
+ hb_set_t visited;
+ hb_set_t roots;
+ find_space_roots (visited, roots);
+
+ // Mark everything not in the subgraphs of the roots as visited. This prevents
+ // subgraphs from being connected via nodes not in those subgraphs.
+ visited.invert ();
+
+ if (!roots) return false;
+
+ while (roots)
+ {
+ unsigned next = HB_SET_VALUE_INVALID;
+ if (unlikely (!check_success (!roots.in_error ()))) break;
+ if (!roots.next (&next)) break;
+
+ hb_set_t connected_roots;
+ find_connected_nodes (next, roots, visited, connected_roots);
+ if (unlikely (!check_success (!connected_roots.in_error ()))) break;
+
+ isolate_subgraph (connected_roots);
+ if (unlikely (!check_success (!connected_roots.in_error ()))) break;
+
+ unsigned next_space = this->next_space ();
+ num_roots_for_space_.push (0);
+ for (unsigned root : connected_roots)
+ {
+ DEBUG_MSG (SUBSET_REPACK, nullptr, "Subgraph %u gets space %u", root, next_space);
+ vertices_[root].space = next_space;
+ num_roots_for_space_[next_space] = num_roots_for_space_[next_space] + 1;
+ distance_invalid = true;
+ positions_invalid = true;
+ }
+
+ // TODO(grieger): special case for GSUB/GPOS use extension promotions to move 16 bit space
+ // into the 32 bit space as needed, instead of using isolation.
+ }
+
+
+
+ return true;
+ }
+
+ /*
+ * Isolates the subgraph of nodes reachable from root. Any links to nodes in the subgraph
+ * that originate from outside of the subgraph will be removed by duplicating the linked to
+ * object.
+ *
+ * Indices stored in roots will be updated if any of the roots are duplicated to new indices.
+ */
+ bool isolate_subgraph (hb_set_t& roots)
+ {
+ update_parents ();
+ hb_map_t subgraph;
+
+ // incoming edges to root_idx should be all 32 bit in length so we don't need to de-dup these
+ // set the subgraph incoming edge count to match all of root_idx's incoming edges
+ hb_set_t parents;
+ for (unsigned root_idx : roots)
+ {
+ subgraph.set (root_idx, wide_parents (root_idx, parents));
+ find_subgraph (root_idx, subgraph);
+ }
+
+ unsigned original_root_idx = root_idx ();
+ hb_map_t index_map;
+ bool made_changes = false;
+ for (auto entry : subgraph.iter ())
+ {
+ const auto& node = vertices_[entry.first];
+ unsigned subgraph_incoming_edges = entry.second;
+
+ if (subgraph_incoming_edges < node.incoming_edges ())
+ {
+ // Only de-dup objects with incoming links from outside the subgraph.
+ made_changes = true;
+ duplicate_subgraph (entry.first, index_map);
+ }
+ }
+
+ if (!made_changes)
+ return false;
+
+ if (original_root_idx != root_idx ()
+ && parents.has (original_root_idx))
+ {
+ // If the root idx has changed since parents was determined, update root idx in parents
+ parents.add (root_idx ());
+ parents.del (original_root_idx);
+ }
+
+ auto new_subgraph =
+ + subgraph.keys ()
+ | hb_map([&] (unsigned node_idx) {
+ const unsigned *v;
+ if (index_map.has (node_idx, &v)) return *v;
+ return node_idx;
+ })
+ ;
+
+ remap_obj_indices (index_map, new_subgraph);
+ remap_obj_indices (index_map, parents.iter (), true);
+
+ // Update roots set with new indices as needed.
+ unsigned next = HB_SET_VALUE_INVALID;
+ while (roots.next (&next))
+ {
+ const unsigned *v;
+ if (index_map.has (next, &v))
+ {
+ roots.del (next);
+ roots.add (*v);
+ }
+ }
+
+ return true;
+ }
+
+ void find_subgraph (unsigned node_idx, hb_map_t& subgraph)
+ {
+ for (const auto& link : vertices_[node_idx].obj.all_links ())
+ {
+ const unsigned *v;
+ if (subgraph.has (link.objidx, &v))
+ {
+ subgraph.set (link.objidx, *v + 1);
+ continue;
+ }
+ subgraph.set (link.objidx, 1);
+ find_subgraph (link.objidx, subgraph);
+ }
+ }
+
+ void find_subgraph (unsigned node_idx, hb_set_t& subgraph)
+ {
+ if (subgraph.has (node_idx)) return;
+ subgraph.add (node_idx);
+ for (const auto& link : vertices_[node_idx].obj.all_links ())
+ find_subgraph (link.objidx, subgraph);
+ }
+
+ size_t find_subgraph_size (unsigned node_idx, hb_set_t& subgraph, unsigned max_depth = -1)
+ {
+ if (subgraph.has (node_idx)) return 0;
+ subgraph.add (node_idx);
+
+ const auto& o = vertices_[node_idx].obj;
+ size_t size = o.tail - o.head;
+ if (max_depth == 0)
+ return size;
+
+ for (const auto& link : o.all_links ())
+ size += find_subgraph_size (link.objidx, subgraph, max_depth - 1);
+ return size;
+ }
+
+ /*
+ * Finds the topmost children of 32bit offsets in the subgraph starting
+ * at node_idx. Found indices are placed into 'found'.
+ */
+ void find_32bit_roots (unsigned node_idx, hb_set_t& found)
+ {
+ for (const auto& link : vertices_[node_idx].obj.all_links ())
+ {
+ if (!link.is_signed && link.width == 4) {
+ found.add (link.objidx);
+ continue;
+ }
+ find_32bit_roots (link.objidx, found);
+ }
+ }
+
+ /*
+ * Moves the child of old_parent_idx pointed to by old_offset to a new
+ * vertex at the new_offset.
+ */
+ template<typename O>
+ void move_child (unsigned old_parent_idx,
+ const O* old_offset,
+ unsigned new_parent_idx,
+ const O* new_offset)
+ {
+ distance_invalid = true;
+ positions_invalid = true;
+
+ auto& old_v = vertices_[old_parent_idx];
+ auto& new_v = vertices_[new_parent_idx];
+
+ unsigned child_id = index_for_offset (old_parent_idx,
+ old_offset);
+
+ auto* new_link = new_v.obj.real_links.push ();
+ new_link->width = O::static_size;
+ new_link->objidx = child_id;
+ new_link->position = (const char*) new_offset - (const char*) new_v.obj.head;
+
+ auto& child = vertices_[child_id];
+ child.parents.push (new_parent_idx);
+
+ old_v.remove_real_link (child_id, old_offset);
+ child.remove_parent (old_parent_idx);
+ }
+
+ /*
+ * duplicates all nodes in the subgraph reachable from node_idx. Does not re-assign
+ * links. index_map is updated with mappings from old id to new id. If a duplication has already
+ * been performed for a given index, then it will be skipped.
+ */
+ void duplicate_subgraph (unsigned node_idx, hb_map_t& index_map)
+ {
+ if (index_map.has (node_idx))
+ return;
+
+ index_map.set (node_idx, duplicate (node_idx));
+ for (const auto& l : object (node_idx).all_links ()) {
+ duplicate_subgraph (l.objidx, index_map);
+ }
+ }
+
+ /*
+ * Creates a copy of node_idx and returns it's new index.
+ */
+ unsigned duplicate (unsigned node_idx)
+ {
+ positions_invalid = true;
+ distance_invalid = true;
+
+ auto* clone = vertices_.push ();
+ auto& child = vertices_[node_idx];
+ if (vertices_.in_error ()) {
+ return -1;
+ }
+
+ clone->obj.head = child.obj.head;
+ clone->obj.tail = child.obj.tail;
+ clone->distance = child.distance;
+ clone->space = child.space;
+ clone->parents.reset ();
+
+ unsigned clone_idx = vertices_.length - 2;
+ for (const auto& l : child.obj.real_links)
+ {
+ clone->obj.real_links.push (l);
+ vertices_[l.objidx].parents.push (clone_idx);
+ }
+ for (const auto& l : child.obj.virtual_links)
+ {
+ clone->obj.virtual_links.push (l);
+ vertices_[l.objidx].parents.push (clone_idx);
+ }
+
+ check_success (!clone->obj.real_links.in_error ());
+ check_success (!clone->obj.virtual_links.in_error ());
+
+ // The last object is the root of the graph, so swap back the root to the end.
+ // The root's obj idx does change, however since it's root nothing else refers to it.
+ // all other obj idx's will be unaffected.
+ hb_swap (vertices_[vertices_.length - 2], *clone);
+
+ // Since the root moved, update the parents arrays of all children on the root.
+ for (const auto& l : root ().obj.all_links ())
+ vertices_[l.objidx].remap_parent (root_idx () - 1, root_idx ());
+
+ return clone_idx;
+ }
+
+ /*
+ * Creates a copy of child and re-assigns the link from
+ * parent to the clone. The copy is a shallow copy, objects
+ * linked from child are not duplicated.
+ */
+ bool duplicate (unsigned parent_idx, unsigned child_idx)
+ {
+ update_parents ();
+
+ unsigned links_to_child = 0;
+ for (const auto& l : vertices_[parent_idx].obj.all_links ())
+ {
+ if (l.objidx == child_idx) links_to_child++;
+ }
+
+ if (vertices_[child_idx].incoming_edges () <= links_to_child)
+ {
+ // Can't duplicate this node, doing so would orphan the original one as all remaining links
+ // to child are from parent.
+ DEBUG_MSG (SUBSET_REPACK, nullptr, " Not duplicating %d => %d",
+ parent_idx, child_idx);
+ return false;
+ }
+
+ DEBUG_MSG (SUBSET_REPACK, nullptr, " Duplicating %d => %d",
+ parent_idx, child_idx);
+
+ unsigned clone_idx = duplicate (child_idx);
+ if (clone_idx == (unsigned) -1) return false;
+ // duplicate shifts the root node idx, so if parent_idx was root update it.
+ if (parent_idx == clone_idx) parent_idx++;
+
+ auto& parent = vertices_[parent_idx];
+ for (auto& l : parent.obj.all_links_writer ())
+ {
+ if (l.objidx != child_idx)
+ continue;
+
+ reassign_link (l, parent_idx, clone_idx);
+ }
+
+ return true;
+ }
+
+
+ /*
+ * Adds a new node to the graph, not connected to anything.
+ */
+ unsigned new_node (char* head, char* tail)
+ {
+ positions_invalid = true;
+ distance_invalid = true;
+
+ auto* clone = vertices_.push ();
+ if (vertices_.in_error ()) {
+ return -1;
+ }
+
+ clone->obj.head = head;
+ clone->obj.tail = tail;
+ clone->distance = 0;
+ clone->space = 0;
+
+ unsigned clone_idx = vertices_.length - 2;
+
+ // The last object is the root of the graph, so swap back the root to the end.
+ // The root's obj idx does change, however since it's root nothing else refers to it.
+ // all other obj idx's will be unaffected.
+ hb_swap (vertices_[vertices_.length - 2], *clone);
+
+ // Since the root moved, update the parents arrays of all children on the root.
+ for (const auto& l : root ().obj.all_links ())
+ vertices_[l.objidx].remap_parent (root_idx () - 1, root_idx ());
+
+ return clone_idx;
+ }
+
+ /*
+ * Raises the sorting priority of all children.
+ */
+ bool raise_childrens_priority (unsigned parent_idx)
+ {
+ DEBUG_MSG (SUBSET_REPACK, nullptr, " Raising priority of all children of %d",
+ parent_idx);
+ // This operation doesn't change ordering until a sort is run, so no need
+ // to invalidate positions. It does not change graph structure so no need
+ // to update distances or edge counts.
+ auto& parent = vertices_[parent_idx].obj;
+ bool made_change = false;
+ for (auto& l : parent.all_links_writer ())
+ made_change |= vertices_[l.objidx].raise_priority ();
+ return made_change;
+ }
+
+ void print_orphaned_nodes ()
+ {
+ if (!DEBUG_ENABLED(SUBSET_REPACK)) return;
+
+ DEBUG_MSG (SUBSET_REPACK, nullptr, "Graph is not fully connected.");
+ parents_invalid = true;
+ update_parents();
+
+ for (unsigned i = 0; i < root_idx (); i++)
+ {
+ const auto& v = vertices_[i];
+ if (!v.parents)
+ DEBUG_MSG (SUBSET_REPACK, nullptr, "Node %u is orphaned.", i);
+ }
+ }
+
+ unsigned num_roots_for_space (unsigned space) const
+ {
+ return num_roots_for_space_[space];
+ }
+
+ unsigned next_space () const
+ {
+ return num_roots_for_space_.length;
+ }
+
+ void move_to_new_space (const hb_set_t& indices)
+ {
+ num_roots_for_space_.push (0);
+ unsigned new_space = num_roots_for_space_.length - 1;
+
+ for (unsigned index : indices) {
+ auto& node = vertices_[index];
+ num_roots_for_space_[node.space] = num_roots_for_space_[node.space] - 1;
+ num_roots_for_space_[new_space] = num_roots_for_space_[new_space] + 1;
+ node.space = new_space;
+ distance_invalid = true;
+ positions_invalid = true;
+ }
+ }
+
+ unsigned space_for (unsigned index, unsigned* root = nullptr) const
+ {
+ const auto& node = vertices_[index];
+ if (node.space)
+ {
+ if (root != nullptr)
+ *root = index;
+ return node.space;
+ }
+
+ if (!node.parents)
+ {
+ if (root)
+ *root = index;
+ return 0;
+ }
+
+ return space_for (node.parents[0], root);
+ }
+
+ void err_other_error () { this->successful = false; }
+
+ size_t total_size_in_bytes () const {
+ size_t total_size = 0;
+ for (unsigned i = 0; i < vertices_.length; i++) {
+ size_t size = vertices_[i].obj.tail - vertices_[i].obj.head;
+ total_size += size;
+ }
+ return total_size;
+ }
+
+
+ private:
+
+ /*
+ * Returns the numbers of incoming edges that are 24 or 32 bits wide.
+ */
+ unsigned wide_parents (unsigned node_idx, hb_set_t& parents) const
+ {
+ unsigned count = 0;
+ hb_set_t visited;
+ for (unsigned p : vertices_[node_idx].parents)
+ {
+ if (visited.has (p)) continue;
+ visited.add (p);
+
+ // Only real links can be wide
+ for (const auto& l : vertices_[p].obj.real_links)
+ {
+ if (l.objidx == node_idx
+ && (l.width == 3 || l.width == 4)
+ && !l.is_signed)
+ {
+ count++;
+ parents.add (p);
+ }
+ }
+ }
+ return count;
+ }
+
+ bool check_success (bool success)
+ { return this->successful && (success || ((void) err_other_error (), false)); }
+
+ public:
+ /*
+ * Creates a map from objid to # of incoming edges.
+ */
+ void update_parents ()
+ {
+ if (!parents_invalid) return;
+
+ for (unsigned i = 0; i < vertices_.length; i++)
+ vertices_[i].parents.reset ();
+
+ for (unsigned p = 0; p < vertices_.length; p++)
+ {
+ for (auto& l : vertices_[p].obj.all_links ())
+ {
+ vertices_[l.objidx].parents.push (p);
+ }
+ }
+
+ parents_invalid = false;
+ }
+
+ /*
+ * compute the serialized start and end positions for each vertex.
+ */
+ void update_positions ()
+ {
+ if (!positions_invalid) return;
+
+ unsigned current_pos = 0;
+ for (int i = root_idx (); i >= 0; i--)
+ {
+ auto& v = vertices_[i];
+ v.start = current_pos;
+ current_pos += v.obj.tail - v.obj.head;
+ v.end = current_pos;
+ }
+
+ positions_invalid = false;
+ }
+
+ /*
+ * Finds the distance to each object in the graph
+ * from the initial node.
+ */
+ void update_distances ()
+ {
+ if (!distance_invalid) return;
+
+ // Uses Dijkstra's algorithm to find all of the shortest distances.
+ // https://en.wikipedia.org/wiki/Dijkstra%27s_algorithm
+ //
+ // Implementation Note:
+ // Since our priority queue doesn't support fast priority decreases
+ // we instead just add new entries into the queue when a priority changes.
+ // Redundant ones are filtered out later on by the visited set.
+ // According to https://www3.cs.stonybrook.edu/~rezaul/papers/TR-07-54.pdf
+ // for practical performance this is faster then using a more advanced queue
+ // (such as a fibonacci queue) with a fast decrease priority.
+ for (unsigned i = 0; i < vertices_.length; i++)
+ {
+ if (i == vertices_.length - 1)
+ vertices_[i].distance = 0;
+ else
+ vertices_[i].distance = hb_int_max (int64_t);
+ }
+
+ hb_priority_queue_t queue;
+ queue.insert (0, vertices_.length - 1);
+
+ hb_vector_t<bool> visited;
+ visited.resize (vertices_.length);
+
+ while (!queue.in_error () && !queue.is_empty ())
+ {
+ unsigned next_idx = queue.pop_minimum ().second;
+ if (visited[next_idx]) continue;
+ const auto& next = vertices_[next_idx];
+ int64_t next_distance = vertices_[next_idx].distance;
+ visited[next_idx] = true;
+
+ for (const auto& link : next.obj.all_links ())
+ {
+ if (visited[link.objidx]) continue;
+
+ const auto& child = vertices_[link.objidx].obj;
+ unsigned link_width = link.width ? link.width : 4; // treat virtual offsets as 32 bits wide
+ int64_t child_weight = (child.tail - child.head) +
+ ((int64_t) 1 << (link_width * 8)) * (vertices_[link.objidx].space + 1);
+ int64_t child_distance = next_distance + child_weight;
+
+ if (child_distance < vertices_[link.objidx].distance)
+ {
+ vertices_[link.objidx].distance = child_distance;
+ queue.insert (child_distance, link.objidx);
+ }
+ }
+ }
+
+ check_success (!queue.in_error ());
+ if (!check_success (queue.is_empty ()))
+ {
+ print_orphaned_nodes ();
+ return;
+ }
+
+ distance_invalid = false;
+ }
+
+ private:
+ /*
+ * Updates a link in the graph to point to a different object. Corrects the
+ * parents vector on the previous and new child nodes.
+ */
+ void reassign_link (hb_serialize_context_t::object_t::link_t& link,
+ unsigned parent_idx,
+ unsigned new_idx)
+ {
+ unsigned old_idx = link.objidx;
+ link.objidx = new_idx;
+ vertices_[old_idx].remove_parent (parent_idx);
+ vertices_[new_idx].parents.push (parent_idx);
+ }
+
+ /*
+ * Updates all objidx's in all links using the provided mapping. Corrects incoming edge counts.
+ */
+ template<typename Iterator, hb_requires (hb_is_iterator (Iterator))>
+ void remap_obj_indices (const hb_map_t& id_map,
+ Iterator subgraph,
+ bool only_wide = false)
+ {
+ if (!id_map) return;
+ for (unsigned i : subgraph)
+ {
+ for (auto& link : vertices_[i].obj.all_links_writer ())
+ {
+ const unsigned *v;
+ if (!id_map.has (link.objidx, &v)) continue;
+ if (only_wide && !(link.width == 4 && !link.is_signed)) continue;
+
+ reassign_link (link, i, *v);
+ }
+ }
+ }
+
+ /*
+ * Updates all objidx's in all links using the provided mapping.
+ */
+ void remap_all_obj_indices (const hb_vector_t<unsigned>& id_map,
+ hb_vector_t<vertex_t>* sorted_graph) const
+ {
+ for (unsigned i = 0; i < sorted_graph->length; i++)
+ {
+ (*sorted_graph)[i].remap_parents (id_map);
+ for (auto& link : (*sorted_graph)[i].obj.all_links_writer ())
+ {
+ link.objidx = id_map[link.objidx];
+ }
+ }
+ }
+
+ /*
+ * Finds all nodes in targets that are reachable from start_idx, nodes in visited will be skipped.
+ * For this search the graph is treated as being undirected.
+ *
+ * Connected targets will be added to connected and removed from targets. All visited nodes
+ * will be added to visited.
+ */
+ void find_connected_nodes (unsigned start_idx,
+ hb_set_t& targets,
+ hb_set_t& visited,
+ hb_set_t& connected)
+ {
+ if (unlikely (!check_success (!visited.in_error ()))) return;
+ if (visited.has (start_idx)) return;
+ visited.add (start_idx);
+
+ if (targets.has (start_idx))
+ {
+ targets.del (start_idx);
+ connected.add (start_idx);
+ }
+
+ const auto& v = vertices_[start_idx];
+
+ // Graph is treated as undirected so search children and parents of start_idx
+ for (const auto& l : v.obj.all_links ())
+ find_connected_nodes (l.objidx, targets, visited, connected);
+
+ for (unsigned p : v.parents)
+ find_connected_nodes (p, targets, visited, connected);
+ }
+
+ public:
+ // TODO(garretrieger): make private, will need to move most of offset overflow code into graph.
+ hb_vector_t<vertex_t> vertices_;
+ hb_vector_t<vertex_t> vertices_scratch_;
+ private:
+ bool parents_invalid;
+ bool distance_invalid;
+ bool positions_invalid;
+ bool successful;
+ hb_vector_t<unsigned> num_roots_for_space_;
+};
+
+}
+
+#endif // GRAPH_GRAPH_HH
diff --git a/thirdparty/harfbuzz/src/graph/gsubgpos-context.cc b/thirdparty/harfbuzz/src/graph/gsubgpos-context.cc
new file mode 100644
index 0000000000..e0ff6ff85f
--- /dev/null
+++ b/thirdparty/harfbuzz/src/graph/gsubgpos-context.cc
@@ -0,0 +1,71 @@
+/*
+ * Copyright © 2022 Google, Inc.
+ *
+ * This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Garret Rieger
+ */
+
+#include "gsubgpos-graph.hh"
+
+namespace graph {
+
+gsubgpos_graph_context_t::gsubgpos_graph_context_t (hb_tag_t table_tag_,
+ graph_t& graph_)
+ : table_tag (table_tag_),
+ graph (graph_),
+ lookup_list_index (0),
+ lookups (),
+ buffers ()
+{
+ if (table_tag_ != HB_OT_TAG_GPOS
+ && table_tag_ != HB_OT_TAG_GSUB)
+ return;
+
+ GSTAR* gstar = graph::GSTAR::graph_to_gstar (graph_);
+ if (gstar) {
+ gstar->find_lookups (graph, lookups);
+ lookup_list_index = gstar->get_lookup_list_index (graph_);
+ }
+}
+
+unsigned gsubgpos_graph_context_t::create_node (unsigned size)
+{
+ char* buffer = (char*) hb_calloc (1, size);
+ if (!buffer)
+ return -1;
+
+ buffers.push (buffer);
+
+ return graph.new_node (buffer, buffer + size);
+}
+
+unsigned gsubgpos_graph_context_t::num_non_ext_subtables () {
+ unsigned count = 0;
+ for (auto l : lookups.values ())
+ {
+ if (l->is_extension (table_tag)) continue;
+ count += l->number_of_subtables ();
+ }
+ return count;
+}
+
+}
diff --git a/thirdparty/harfbuzz/src/graph/gsubgpos-context.hh b/thirdparty/harfbuzz/src/graph/gsubgpos-context.hh
new file mode 100644
index 0000000000..49b24198ff
--- /dev/null
+++ b/thirdparty/harfbuzz/src/graph/gsubgpos-context.hh
@@ -0,0 +1,67 @@
+/*
+ * Copyright © 2022 Google, Inc.
+ *
+ * This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Garret Rieger
+ */
+
+#include "graph.hh"
+#include "../hb-ot-layout-gsubgpos.hh"
+
+#ifndef GRAPH_GSUBGPOS_CONTEXT_HH
+#define GRAPH_GSUBGPOS_CONTEXT_HH
+
+namespace graph {
+
+struct Lookup;
+
+struct gsubgpos_graph_context_t
+{
+ hb_tag_t table_tag;
+ graph_t& graph;
+ unsigned lookup_list_index;
+ hb_hashmap_t<unsigned, graph::Lookup*> lookups;
+ hb_vector_t<char*> buffers;
+
+ HB_INTERNAL gsubgpos_graph_context_t (hb_tag_t table_tag_,
+ graph_t& graph_);
+
+ ~gsubgpos_graph_context_t ()
+ {
+ for (char* b : buffers)
+ hb_free (b);
+ }
+
+ HB_INTERNAL unsigned create_node (unsigned size);
+
+ void add_buffer (char* buffer)
+ {
+ buffers.push (buffer);
+ }
+
+ private:
+ HB_INTERNAL unsigned num_non_ext_subtables ();
+};
+
+}
+
+#endif // GRAPH_GSUBGPOS_CONTEXT
diff --git a/thirdparty/harfbuzz/src/graph/gsubgpos-graph.hh b/thirdparty/harfbuzz/src/graph/gsubgpos-graph.hh
new file mode 100644
index 0000000000..afa1152c44
--- /dev/null
+++ b/thirdparty/harfbuzz/src/graph/gsubgpos-graph.hh
@@ -0,0 +1,351 @@
+/*
+ * Copyright © 2022 Google, Inc.
+ *
+ * This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Garret Rieger
+ */
+
+#include "graph.hh"
+#include "../hb-ot-layout-gsubgpos.hh"
+#include "../OT/Layout/GSUB/ExtensionSubst.hh"
+#include "gsubgpos-context.hh"
+#include "pairpos-graph.hh"
+
+#ifndef GRAPH_GSUBGPOS_GRAPH_HH
+#define GRAPH_GSUBGPOS_GRAPH_HH
+
+namespace graph {
+
+struct Lookup;
+
+template<typename T>
+struct ExtensionFormat1 : public OT::ExtensionFormat1<T>
+{
+ void reset(unsigned type)
+ {
+ this->format = 1;
+ this->extensionLookupType = type;
+ this->extensionOffset = 0;
+ }
+
+ bool sanitize (graph_t::vertex_t& vertex) const
+ {
+ int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+ return vertex_len >= OT::ExtensionFormat1<T>::static_size;
+ }
+
+ unsigned get_lookup_type () const
+ {
+ return this->extensionLookupType;
+ }
+
+ unsigned get_subtable_index (graph_t& graph, unsigned this_index) const
+ {
+ return graph.index_for_offset (this_index, &this->extensionOffset);
+ }
+};
+
+struct Lookup : public OT::Lookup
+{
+ unsigned number_of_subtables () const
+ {
+ return subTable.len;
+ }
+
+ bool sanitize (graph_t::vertex_t& vertex) const
+ {
+ int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+ if (vertex_len < OT::Lookup::min_size) return false;
+ return vertex_len >= this->get_size ();
+ }
+
+ bool is_extension (hb_tag_t table_tag) const
+ {
+ return lookupType == extension_type (table_tag);
+ }
+
+ bool make_extension (gsubgpos_graph_context_t& c,
+ unsigned this_index)
+ {
+ unsigned type = lookupType;
+ unsigned ext_type = extension_type (c.table_tag);
+ if (!ext_type || is_extension (c.table_tag))
+ {
+ // NOOP
+ return true;
+ }
+
+ DEBUG_MSG (SUBSET_REPACK, nullptr,
+ "Promoting lookup type %u (obj %u) to extension.",
+ type,
+ this_index);
+
+ for (unsigned i = 0; i < subTable.len; i++)
+ {
+ unsigned subtable_index = c.graph.index_for_offset (this_index, &subTable[i]);
+ if (!make_subtable_extension (c,
+ this_index,
+ subtable_index))
+ return false;
+ }
+
+ lookupType = ext_type;
+ return true;
+ }
+
+ bool split_subtables_if_needed (gsubgpos_graph_context_t& c,
+ unsigned this_index)
+ {
+ unsigned type = lookupType;
+ bool is_ext = is_extension (c.table_tag);
+
+ if (c.table_tag != HB_OT_TAG_GPOS)
+ return true;
+
+ if (!is_ext && type != OT::Layout::GPOS_impl::PosLookupSubTable::Type::Pair)
+ return true;
+
+ hb_vector_t<unsigned> all_new_subtables;
+ for (unsigned i = 0; i < subTable.len; i++)
+ {
+ unsigned subtable_index = c.graph.index_for_offset (this_index, &subTable[i]);
+ if (is_ext) {
+ unsigned ext_subtable_index = subtable_index;
+ ExtensionFormat1<OT::Layout::GSUB_impl::ExtensionSubst>* extension =
+ (ExtensionFormat1<OT::Layout::GSUB_impl::ExtensionSubst>*)
+ c.graph.object (ext_subtable_index).head;
+ if (!extension->sanitize (c.graph.vertices_[ext_subtable_index]))
+ continue;
+
+ subtable_index = extension->get_subtable_index (c.graph, ext_subtable_index);
+ type = extension->get_lookup_type ();
+ if (type != OT::Layout::GPOS_impl::PosLookupSubTable::Type::Pair)
+ continue;
+ }
+
+ PairPos* pairPos = (PairPos*) c.graph.object (subtable_index).head;
+ if (!pairPos->sanitize (c.graph.vertices_[subtable_index])) continue;
+
+ hb_vector_t<unsigned> new_sub_tables = pairPos->split_subtables (c, subtable_index);
+ if (new_sub_tables.in_error ()) return false;
+ + new_sub_tables.iter() | hb_sink (all_new_subtables);
+ }
+
+ if (all_new_subtables)
+ add_sub_tables (c, this_index, type, all_new_subtables);
+
+ return true;
+ }
+
+ void add_sub_tables (gsubgpos_graph_context_t& c,
+ unsigned this_index,
+ unsigned type,
+ hb_vector_t<unsigned>& subtable_indices)
+ {
+ bool is_ext = is_extension (c.table_tag);
+ auto& v = c.graph.vertices_[this_index];
+
+ size_t new_size = v.table_size ()
+ + subtable_indices.length * OT::Offset16::static_size;
+ char* buffer = (char*) hb_calloc (1, new_size);
+ c.add_buffer (buffer);
+ memcpy (buffer, v.obj.head, v.table_size());
+
+ v.obj.head = buffer;
+ v.obj.tail = buffer + new_size;
+
+ Lookup* new_lookup = (Lookup*) buffer;
+
+ new_lookup->subTable.len = subTable.len + subtable_indices.length;
+ unsigned offset_index = subTable.len;
+ for (unsigned subtable_id : subtable_indices)
+ {
+ if (is_ext)
+ {
+ unsigned ext_id = create_extension_subtable (c, subtable_id, type);
+ c.graph.vertices_[subtable_id].parents.push (ext_id);
+ subtable_id = ext_id;
+ }
+
+ auto* link = v.obj.real_links.push ();
+ link->width = 2;
+ link->objidx = subtable_id;
+ link->position = (char*) &new_lookup->subTable[offset_index++] -
+ (char*) new_lookup;
+ c.graph.vertices_[subtable_id].parents.push (this_index);
+ }
+
+ // The head location of the lookup has changed, invalidating the lookups map entry
+ // in the context. Update the map.
+ c.lookups.set (this_index, new_lookup);
+ }
+
+ unsigned create_extension_subtable (gsubgpos_graph_context_t& c,
+ unsigned subtable_index,
+ unsigned type)
+ {
+ unsigned extension_size = OT::ExtensionFormat1<OT::Layout::GSUB_impl::ExtensionSubst>::static_size;
+
+ unsigned ext_index = c.create_node (extension_size);
+ if (ext_index == (unsigned) -1)
+ return -1;
+
+ auto& ext_vertex = c.graph.vertices_[ext_index];
+ ExtensionFormat1<OT::Layout::GSUB_impl::ExtensionSubst>* extension =
+ (ExtensionFormat1<OT::Layout::GSUB_impl::ExtensionSubst>*) ext_vertex.obj.head;
+ extension->reset (type);
+
+ // Make extension point at the subtable.
+ auto* l = ext_vertex.obj.real_links.push ();
+
+ l->width = 4;
+ l->objidx = subtable_index;
+ l->position = 4;
+
+ return ext_index;
+ }
+
+ bool make_subtable_extension (gsubgpos_graph_context_t& c,
+ unsigned lookup_index,
+ unsigned subtable_index)
+ {
+ unsigned type = lookupType;
+
+ unsigned ext_index = create_extension_subtable(c, subtable_index, type);
+ if (ext_index == (unsigned) -1)
+ return false;
+
+ auto& lookup_vertex = c.graph.vertices_[lookup_index];
+ for (auto& l : lookup_vertex.obj.real_links.writer ())
+ {
+ if (l.objidx == subtable_index)
+ // Change lookup to point at the extension.
+ l.objidx = ext_index;
+ }
+
+ // Make extension point at the subtable.
+ auto& ext_vertex = c.graph.vertices_[ext_index];
+ auto& subtable_vertex = c.graph.vertices_[subtable_index];
+ ext_vertex.parents.push (lookup_index);
+ subtable_vertex.remap_parent (lookup_index, ext_index);
+
+ return true;
+ }
+
+ private:
+ unsigned extension_type (hb_tag_t table_tag) const
+ {
+ switch (table_tag)
+ {
+ case HB_OT_TAG_GPOS: return 9;
+ case HB_OT_TAG_GSUB: return 7;
+ default: return 0;
+ }
+ }
+};
+
+template <typename T>
+struct LookupList : public OT::LookupList<T>
+{
+ bool sanitize (const graph_t::vertex_t& vertex) const
+ {
+ int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+ if (vertex_len < OT::LookupList<T>::min_size) return false;
+ return vertex_len >= OT::LookupList<T>::item_size * this->len;
+ }
+};
+
+struct GSTAR : public OT::GSUBGPOS
+{
+ static GSTAR* graph_to_gstar (graph_t& graph)
+ {
+ const auto& r = graph.root ();
+
+ GSTAR* gstar = (GSTAR*) r.obj.head;
+ if (!gstar->sanitize (r))
+ return nullptr;
+
+ return gstar;
+ }
+
+ const void* get_lookup_list_field_offset () const
+ {
+ switch (u.version.major) {
+ case 1: return u.version1.get_lookup_list_offset ();
+#ifndef HB_NO_BORING_EXPANSION
+ case 2: return u.version2.get_lookup_list_offset ();
+#endif
+ default: return 0;
+ }
+ }
+
+ bool sanitize (const graph_t::vertex_t& vertex)
+ {
+ int64_t len = vertex.obj.tail - vertex.obj.head;
+ if (len < OT::GSUBGPOS::min_size) return false;
+ return len >= get_size ();
+ }
+
+ void find_lookups (graph_t& graph,
+ hb_hashmap_t<unsigned, Lookup*>& lookups /* OUT */)
+ {
+ switch (u.version.major) {
+ case 1: find_lookups<SmallTypes> (graph, lookups); break;
+#ifndef HB_NO_BORING_EXPANSION
+ case 2: find_lookups<MediumTypes> (graph, lookups); break;
+#endif
+ }
+ }
+
+ unsigned get_lookup_list_index (graph_t& graph)
+ {
+ return graph.index_for_offset (graph.root_idx (),
+ get_lookup_list_field_offset());
+ }
+
+ template<typename Types>
+ void find_lookups (graph_t& graph,
+ hb_hashmap_t<unsigned, Lookup*>& lookups /* OUT */)
+ {
+ unsigned lookup_list_idx = get_lookup_list_index (graph);
+
+ const LookupList<Types>* lookupList =
+ (const LookupList<Types>*) graph.object (lookup_list_idx).head;
+ if (!lookupList->sanitize (graph.vertices_[lookup_list_idx]))
+ return;
+
+ for (unsigned i = 0; i < lookupList->len; i++)
+ {
+ unsigned lookup_idx = graph.index_for_offset (lookup_list_idx, &(lookupList->arrayZ[i]));
+ Lookup* lookup = (Lookup*) graph.object (lookup_idx).head;
+ if (!lookup->sanitize (graph.vertices_[lookup_idx])) continue;
+ lookups.set (lookup_idx, lookup);
+ }
+ }
+};
+
+
+
+
+}
+
+#endif /* GRAPH_GSUBGPOS_GRAPH_HH */
diff --git a/thirdparty/harfbuzz/src/graph/pairpos-graph.hh b/thirdparty/harfbuzz/src/graph/pairpos-graph.hh
new file mode 100644
index 0000000000..3ca4fc701c
--- /dev/null
+++ b/thirdparty/harfbuzz/src/graph/pairpos-graph.hh
@@ -0,0 +1,299 @@
+/*
+ * Copyright © 2022 Google, Inc.
+ *
+ * This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Garret Rieger
+ */
+
+#ifndef GRAPH_PAIRPOS_GRAPH_HH
+#define GRAPH_PAIRPOS_GRAPH_HH
+
+#include "coverage-graph.hh"
+#include "../OT/Layout/GPOS/PairPos.hh"
+#include "../OT/Layout/GPOS/PosLookupSubTable.hh"
+
+namespace graph {
+
+struct PairPosFormat1 : public OT::Layout::GPOS_impl::PairPosFormat1_3<SmallTypes>
+{
+ bool sanitize (graph_t::vertex_t& vertex) const
+ {
+ int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+ unsigned min_size = OT::Layout::GPOS_impl::PairPosFormat1_3<SmallTypes>::min_size;
+ if (vertex_len < min_size) return false;
+
+ return vertex_len >=
+ min_size + pairSet.get_size () - pairSet.len.get_size();
+ }
+
+ hb_vector_t<unsigned> split_subtables (gsubgpos_graph_context_t& c, unsigned this_index)
+ {
+ hb_set_t visited;
+
+ const unsigned coverage_id = c.graph.index_for_offset (this_index, &coverage);
+ const unsigned coverage_size = c.graph.vertices_[coverage_id].table_size ();
+ const unsigned base_size = OT::Layout::GPOS_impl::PairPosFormat1_3<SmallTypes>::min_size
+ + coverage_size;
+
+ unsigned accumulated = base_size;
+ hb_vector_t<unsigned> split_points;
+ for (unsigned i = 0; i < pairSet.len; i++)
+ {
+ unsigned pair_set_index = pair_set_graph_index (c, this_index, i);
+ accumulated += c.graph.find_subgraph_size (pair_set_index, visited);
+ accumulated += SmallTypes::size; // for PairSet offset.
+
+ // TODO(garretrieger): don't count the size of the largest pairset against the limit, since
+ // it will be packed last in the order and does not contribute to
+ // the 64kb limit.
+
+ if (accumulated > (1 << 16))
+ {
+ split_points.push (i);
+ accumulated = base_size;
+ visited.clear (); // Pretend node sharing isn't allowed between splits.
+ }
+ }
+
+ return do_split (c, this_index, split_points);
+ }
+
+ private:
+
+ // Split this PairPos into two or more PairPos's. split_points defines
+ // the indices (first index to include in the new table) to split at.
+ // Returns the object id's of the newly created PairPos subtables.
+ hb_vector_t<unsigned> do_split (gsubgpos_graph_context_t& c,
+ unsigned this_index,
+ const hb_vector_t<unsigned> split_points)
+ {
+ hb_vector_t<unsigned> new_objects;
+ if (!split_points)
+ return new_objects;
+
+ for (unsigned i = 0; i < split_points.length; i++)
+ {
+ unsigned start = split_points[i];
+ unsigned end = (i < split_points.length - 1) ? split_points[i + 1] : pairSet.len;
+ unsigned id = clone_range (c, this_index, start, end);
+
+ if (id == (unsigned) -1)
+ {
+ new_objects.reset ();
+ new_objects.allocated = -1; // mark error
+ return new_objects;
+ }
+ new_objects.push (id);
+ }
+
+ if (!shrink (c, this_index, split_points[0]))
+ {
+ new_objects.reset ();
+ new_objects.allocated = -1; // mark error
+ }
+
+ return new_objects;
+ }
+
+ bool shrink (gsubgpos_graph_context_t& c,
+ unsigned this_index,
+ unsigned count)
+ {
+ DEBUG_MSG (SUBSET_REPACK, nullptr,
+ " Shrinking PairPosFormat1 (%u) to [0, %u).",
+ this_index,
+ count);
+ unsigned old_count = pairSet.len;
+ if (count >= old_count)
+ return true;
+
+ pairSet.len = count;
+ c.graph.vertices_[this_index].obj.tail -= (old_count - count) * SmallTypes::size;
+
+ unsigned coverage_id = c.graph.index_for_offset (this_index, &coverage);
+ unsigned coverage_size = c.graph.vertices_[coverage_id].table_size ();
+ auto& coverage_v = c.graph.vertices_[coverage_id];
+ Coverage* coverage_table = (Coverage*) coverage_v.obj.head;
+ if (!coverage_table->sanitize (coverage_v))
+ return false;
+
+ auto new_coverage =
+ + hb_zip (coverage_table->iter (), hb_range ())
+ | hb_filter ([&] (hb_pair_t<unsigned, unsigned> p) {
+ return p.second < count;
+ })
+ | hb_map_retains_sorting (hb_first)
+ ;
+
+ return make_coverage (c, new_coverage, coverage_id, coverage_size);
+ }
+
+ // Create a new PairPos including PairSet's from start (inclusive) to end (exclusive).
+ // Returns object id of the new object.
+ unsigned clone_range (gsubgpos_graph_context_t& c,
+ unsigned this_index,
+ unsigned start, unsigned end) const
+ {
+ DEBUG_MSG (SUBSET_REPACK, nullptr,
+ " Cloning PairPosFormat1 (%u) range [%u, %u).", this_index, start, end);
+
+ unsigned num_pair_sets = end - start;
+ unsigned prime_size = OT::Layout::GPOS_impl::PairPosFormat1_3<SmallTypes>::min_size
+ + num_pair_sets * SmallTypes::size;
+
+ unsigned pair_pos_prime_id = c.create_node (prime_size);
+ if (pair_pos_prime_id == (unsigned) -1) return -1;
+
+ PairPosFormat1* pair_pos_prime = (PairPosFormat1*) c.graph.object (pair_pos_prime_id).head;
+ pair_pos_prime->format = this->format;
+ pair_pos_prime->valueFormat[0] = this->valueFormat[0];
+ pair_pos_prime->valueFormat[1] = this->valueFormat[1];
+ pair_pos_prime->pairSet.len = num_pair_sets;
+
+ for (unsigned i = start; i < end; i++)
+ {
+ c.graph.move_child<> (this_index,
+ &pairSet[i],
+ pair_pos_prime_id,
+ &pair_pos_prime->pairSet[i - start]);
+ }
+
+ unsigned coverage_id = c.graph.index_for_offset (this_index, &coverage);
+ unsigned coverage_size = c.graph.vertices_[coverage_id].table_size ();
+ auto& coverage_v = c.graph.vertices_[coverage_id];
+ Coverage* coverage_table = (Coverage*) coverage_v.obj.head;
+ if (!coverage_table->sanitize (coverage_v))
+ return false;
+
+ auto new_coverage =
+ + hb_zip (coverage_table->iter (), hb_range ())
+ | hb_filter ([&] (hb_pair_t<unsigned, unsigned> p) {
+ return p.second >= start && p.second < end;
+ })
+ | hb_map_retains_sorting (hb_first)
+ ;
+
+ unsigned coverage_prime_id = c.graph.new_node (nullptr, nullptr);
+ auto& coverage_prime_vertex = c.graph.vertices_[coverage_prime_id];
+ if (!make_coverage (c, new_coverage, coverage_prime_id, coverage_size))
+ return -1;
+
+ auto* coverage_link = c.graph.vertices_[pair_pos_prime_id].obj.real_links.push ();
+ coverage_link->width = SmallTypes::size;
+ coverage_link->objidx = coverage_prime_id;
+ coverage_link->position = 2;
+ coverage_prime_vertex.parents.push (pair_pos_prime_id);
+
+ return pair_pos_prime_id;
+ }
+
+ template<typename It>
+ bool make_coverage (gsubgpos_graph_context_t& c,
+ It glyphs,
+ unsigned dest_obj,
+ unsigned max_size) const
+ {
+ char* buffer = (char*) hb_calloc (1, max_size);
+ hb_serialize_context_t serializer (buffer, max_size);
+ Coverage_serialize (&serializer, glyphs);
+ serializer.end_serialize ();
+ if (serializer.in_error ())
+ {
+ hb_free (buffer);
+ return false;
+ }
+
+ hb_bytes_t coverage_copy = serializer.copy_bytes ();
+ c.add_buffer ((char *) coverage_copy.arrayZ); // Give ownership to the context, it will cleanup the buffer.
+
+ auto& obj = c.graph.vertices_[dest_obj].obj;
+ obj.head = (char *) coverage_copy.arrayZ;
+ obj.tail = obj.head + coverage_copy.length;
+
+ hb_free (buffer);
+ return true;
+ }
+
+ unsigned pair_set_graph_index (gsubgpos_graph_context_t& c, unsigned this_index, unsigned i) const
+ {
+ return c.graph.index_for_offset (this_index, &pairSet[i]);
+ }
+};
+
+struct PairPosFormat2 : public OT::Layout::GPOS_impl::PairPosFormat2_4<SmallTypes>
+{
+ bool sanitize (graph_t::vertex_t& vertex) const
+ {
+ // TODO(garretrieger): implement me!
+ return true;
+ }
+
+ hb_vector_t<unsigned> split_subtables (gsubgpos_graph_context_t& c, unsigned this_index)
+ {
+ // TODO(garretrieger): implement me!
+ return hb_vector_t<unsigned> ();
+ }
+};
+
+struct PairPos : public OT::Layout::GPOS_impl::PairPos
+{
+ hb_vector_t<unsigned> split_subtables (gsubgpos_graph_context_t& c, unsigned this_index)
+ {
+ switch (u.format) {
+ case 1:
+ return ((PairPosFormat1*)(&u.format1))->split_subtables (c, this_index);
+ case 2:
+ return ((PairPosFormat2*)(&u.format2))->split_subtables (c, this_index);
+#ifndef HB_NO_BORING_EXPANSION
+ case 3: HB_FALLTHROUGH;
+ case 4: HB_FALLTHROUGH;
+ // Don't split 24bit PairPos's.
+#endif
+ default:
+ return hb_vector_t<unsigned> ();
+ }
+ }
+
+ bool sanitize (graph_t::vertex_t& vertex) const
+ {
+ int64_t vertex_len = vertex.obj.tail - vertex.obj.head;
+ if (vertex_len < u.format.get_size ()) return false;
+
+ switch (u.format) {
+ case 1:
+ return ((PairPosFormat1*)(&u.format1))->sanitize (vertex);
+ case 2:
+ return ((PairPosFormat2*)(&u.format2))->sanitize (vertex);
+#ifndef HB_NO_BORING_EXPANSION
+ case 3: HB_FALLTHROUGH;
+ case 4: HB_FALLTHROUGH;
+#endif
+ default:
+ // We don't handle format 3 and 4 here.
+ return false;
+ }
+ }
+};
+
+}
+
+#endif // GRAPH_PAIRPOS_GRAPH_HH
diff --git a/thirdparty/harfbuzz/src/graph/serialize.hh b/thirdparty/harfbuzz/src/graph/serialize.hh
new file mode 100644
index 0000000000..ecc6cc5aea
--- /dev/null
+++ b/thirdparty/harfbuzz/src/graph/serialize.hh
@@ -0,0 +1,249 @@
+/*
+ * Copyright © 2022 Google, Inc.
+ *
+ * This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Garret Rieger
+ */
+
+#ifndef GRAPH_SERIALIZE_HH
+#define GRAPH_SERIALIZE_HH
+
+namespace graph {
+
+struct overflow_record_t
+{
+ unsigned parent;
+ unsigned child;
+};
+
+inline
+int64_t compute_offset (
+ const graph_t& graph,
+ unsigned parent_idx,
+ const hb_serialize_context_t::object_t::link_t& link)
+{
+ const auto& parent = graph.vertices_[parent_idx];
+ const auto& child = graph.vertices_[link.objidx];
+ int64_t offset = 0;
+ switch ((hb_serialize_context_t::whence_t) link.whence) {
+ case hb_serialize_context_t::whence_t::Head:
+ offset = child.start - parent.start; break;
+ case hb_serialize_context_t::whence_t::Tail:
+ offset = child.start - parent.end; break;
+ case hb_serialize_context_t::whence_t::Absolute:
+ offset = child.start; break;
+ }
+
+ assert (offset >= link.bias);
+ offset -= link.bias;
+ return offset;
+}
+
+inline
+bool is_valid_offset (int64_t offset,
+ const hb_serialize_context_t::object_t::link_t& link)
+{
+ if (unlikely (!link.width))
+ // Virtual links can't overflow.
+ return link.is_signed || offset >= 0;
+
+ if (link.is_signed)
+ {
+ if (link.width == 4)
+ return offset >= -((int64_t) 1 << 31) && offset < ((int64_t) 1 << 31);
+ else
+ return offset >= -(1 << 15) && offset < (1 << 15);
+ }
+ else
+ {
+ if (link.width == 4)
+ return offset >= 0 && offset < ((int64_t) 1 << 32);
+ else if (link.width == 3)
+ return offset >= 0 && offset < ((int32_t) 1 << 24);
+ else
+ return offset >= 0 && offset < (1 << 16);
+ }
+}
+
+/*
+ * Will any offsets overflow on graph when it's serialized?
+ */
+inline bool
+will_overflow (graph_t& graph,
+ hb_vector_t<overflow_record_t>* overflows = nullptr)
+{
+ if (overflows) overflows->resize (0);
+ graph.update_positions ();
+
+ const auto& vertices = graph.vertices_;
+ for (int parent_idx = vertices.length - 1; parent_idx >= 0; parent_idx--)
+ {
+ // Don't need to check virtual links for overflow
+ for (const auto& link : vertices[parent_idx].obj.real_links)
+ {
+ int64_t offset = compute_offset (graph, parent_idx, link);
+ if (is_valid_offset (offset, link))
+ continue;
+
+ if (!overflows) return true;
+
+ overflow_record_t r;
+ r.parent = parent_idx;
+ r.child = link.objidx;
+ overflows->push (r);
+ }
+ }
+
+ if (!overflows) return false;
+ return overflows->length;
+}
+
+inline
+void print_overflows (graph_t& graph,
+ const hb_vector_t<overflow_record_t>& overflows)
+{
+ if (!DEBUG_ENABLED(SUBSET_REPACK)) return;
+
+ graph.update_parents ();
+ int limit = 10;
+ for (const auto& o : overflows)
+ {
+ if (!limit--) break;
+ const auto& parent = graph.vertices_[o.parent];
+ const auto& child = graph.vertices_[o.child];
+ DEBUG_MSG (SUBSET_REPACK, nullptr,
+ " overflow from "
+ "%4d (%4d in, %4d out, space %2d) => "
+ "%4d (%4d in, %4d out, space %2d)",
+ o.parent,
+ parent.incoming_edges (),
+ parent.obj.real_links.length + parent.obj.virtual_links.length,
+ graph.space_for (o.parent),
+ o.child,
+ child.incoming_edges (),
+ child.obj.real_links.length + child.obj.virtual_links.length,
+ graph.space_for (o.child));
+ }
+ if (overflows.length > 10) {
+ DEBUG_MSG (SUBSET_REPACK, nullptr, " ... plus %d more overflows.", overflows.length - 10);
+ }
+}
+
+template <typename O> inline void
+serialize_link_of_type (const hb_serialize_context_t::object_t::link_t& link,
+ char* head,
+ hb_serialize_context_t* c)
+{
+ OT::Offset<O>* offset = reinterpret_cast<OT::Offset<O>*> (head + link.position);
+ *offset = 0;
+ c->add_link (*offset,
+ // serializer has an extra nil object at the start of the
+ // object array. So all id's are +1 of what our id's are.
+ link.objidx + 1,
+ (hb_serialize_context_t::whence_t) link.whence,
+ link.bias);
+}
+
+inline
+void serialize_link (const hb_serialize_context_t::object_t::link_t& link,
+ char* head,
+ hb_serialize_context_t* c)
+{
+ switch (link.width)
+ {
+ case 0:
+ // Virtual links aren't serialized.
+ return;
+ case 4:
+ if (link.is_signed)
+ {
+ serialize_link_of_type<OT::HBINT32> (link, head, c);
+ } else {
+ serialize_link_of_type<OT::HBUINT32> (link, head, c);
+ }
+ return;
+ case 2:
+ if (link.is_signed)
+ {
+ serialize_link_of_type<OT::HBINT16> (link, head, c);
+ } else {
+ serialize_link_of_type<OT::HBUINT16> (link, head, c);
+ }
+ return;
+ case 3:
+ serialize_link_of_type<OT::HBUINT24> (link, head, c);
+ return;
+ default:
+ // Unexpected link width.
+ assert (0);
+ }
+}
+
+/*
+ * serialize graph into the provided serialization buffer.
+ */
+inline hb_blob_t* serialize (const graph_t& graph)
+{
+ hb_vector_t<char> buffer;
+ size_t size = graph.total_size_in_bytes ();
+ if (!buffer.alloc (size)) {
+ DEBUG_MSG (SUBSET_REPACK, nullptr, "Unable to allocate output buffer.");
+ return nullptr;
+ }
+ hb_serialize_context_t c((void *) buffer, size);
+
+ c.start_serialize<void> ();
+ const auto& vertices = graph.vertices_;
+ for (unsigned i = 0; i < vertices.length; i++) {
+ c.push ();
+
+ size_t size = vertices[i].obj.tail - vertices[i].obj.head;
+ char* start = c.allocate_size <char> (size);
+ if (!start) {
+ DEBUG_MSG (SUBSET_REPACK, nullptr, "Buffer out of space.");
+ return nullptr;
+ }
+
+ memcpy (start, vertices[i].obj.head, size);
+
+ // Only real links needs to be serialized.
+ for (const auto& link : vertices[i].obj.real_links)
+ serialize_link (link, start, &c);
+
+ // All duplications are already encoded in the graph, so don't
+ // enable sharing during packing.
+ c.pop_pack (false);
+ }
+ c.end_serialize ();
+
+ if (c.in_error ()) {
+ DEBUG_MSG (SUBSET_REPACK, nullptr, "Error during serialization. Err flag: %d",
+ c.errors);
+ return nullptr;
+ }
+
+ return c.copy_blob ();
+}
+
+} // namespace graph
+
+#endif // GRAPH_SERIALIZE_HH