Roll HarfBuzz to 0.9.32

third_party/harfbuzz-ng/src/hb-ot-map.cc

 /*
  * Copyright © 2009,2010  Red Hat, Inc.
  * Copyright © 2010,2011,2013  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
@@ skipping 81 matching lines @@
     found_script[table_index] = hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index], &chosen_script[table_index]);
     hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]);
   }
 }
 
 void hb_ot_map_builder_t::add_feature (hb_tag_t tag, unsigned int value,
                                        hb_ot_map_feature_flags_t flags)
 {
   feature_info_t *info = feature_infos.push();
   if (unlikely (!info)) return;
+  if (unlikely (!tag)) return;
   info->tag = tag;
   info->seq = feature_infos.len;
   info->max_value = value;
   info->flags = flags;
   info->default_value = (flags & F_GLOBAL) ? value : 0;
   info->stage[0] = current_stage[0];
   info->stage[1] = current_stage[1];
 }
 
 
@@ skipping 12 matching lines @@
   }
 
   current_stage[table_index]++;
 }
 
 void
 hb_ot_map_builder_t::compile (hb_ot_map_t &m)
 {
   m.global_mask = 1;
 
-  for (unsigned int table_index = 0; table_index < 2; table_index++) {
+  unsigned int required_feature_index[2];
+  hb_tag_t required_feature_tag[2];
+  /* We default to applying required feature in stage 0.  If the required
+   * feature has a tag that is known to the shaper, we apply required feature
+   * in the stage for that tag.
+   */
+  unsigned int required_feature_stage[2] = {0, 0};
+
+  for (unsigned int table_index = 0; table_index < 2; table_index++)
+  {
     m.chosen_script[table_index] = chosen_script[table_index];
     m.found_script[table_index] = found_script[table_index];
+
+    hb_ot_layout_language_get_required_feature (face,
+                                                table_tags[table_index],
+                                                script_index[table_index],
+                                                language_index[table_index],
+                                                &required_feature_index[table_index],
+                                                &required_feature_tag[table_index]);
   }
 
   if (!feature_infos.len)
     return;
 
   /* Sort features and merge duplicates */
   {
-    feature_infos.sort ();
+    feature_infos.qsort ();
     unsigned int j = 0;
     for (unsigned int i = 1; i < feature_infos.len; i++)
       if (feature_infos[i].tag != feature_infos[j].tag)
         feature_infos[++j] = feature_infos[i];
       else {
         if (feature_infos[i].flags & F_GLOBAL) {
           feature_infos[j].flags |= F_GLOBAL;
           feature_infos[j].max_value = feature_infos[i].max_value;
           feature_infos[j].default_value = feature_infos[i].default_value;
         } else {
           feature_infos[j].flags &= ~F_GLOBAL;
           feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value);
           /* Inherit default_value from j */
         }
         feature_infos[j].flags |= (feature_infos[i].flags & F_HAS_FALLBACK);
         feature_infos[j].stage[0] = MIN (feature_infos[j].stage[0], feature_infos[i].stage[0]);
         feature_infos[j].stage[1] = MIN (feature_infos[j].stage[1], feature_infos[i].stage[1]);
       }
     feature_infos.shrink (j + 1);
   }
 
 
   /* Allocate bits now */
   unsigned int next_bit = 1;
-  for (unsigned int i = 0; i < feature_infos.len; i++) {
+  for (unsigned int i = 0; i < feature_infos.len; i++)
+  {
     const feature_info_t *info = &feature_infos[i];
 
     unsigned int bits_needed;
 
     if ((info->flags & F_GLOBAL) && info->max_value == 1)
       /* Uses the global bit */
       bits_needed = 0;
     else
       bits_needed = _hb_bit_storage (info->max_value);
 
     if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t))
       continue; /* Feature disabled, or not enough bits. */
 
 
     hb_bool_t found = false;
     unsigned int feature_index[2];
     for (unsigned int table_index = 0; table_index < 2; table_index++)
+    {
+      if (required_feature_tag[table_index] == info->tag)
+      {
+        required_feature_stage[table_index] = info->stage[table_index];
+        found = true;
+        continue;
+      }
       found |= hb_ot_layout_language_find_feature (face,
                                                    table_tags[table_index],
                                                    script_index[table_index],
                                                    language_index[table_index],
                                                    info->tag,
                                                    &feature_index[table_index]);
+    }
     if (!found && !(info->flags & F_HAS_FALLBACK))
       continue;
 
 
     hb_ot_map_t::feature_map_t *map = m.features.push ();
     if (unlikely (!map))
       break;
 
     map->tag = info->tag;
     map->index[0] = feature_index[0];
@@ skipping 14 matching lines @@
     map->_1_mask = (1 << map->shift) & map->mask;
     map->needs_fallback = !found;
 
   }
   feature_infos.shrink (0); /* Done with these */
 
 
   add_gsub_pause (NULL);
   add_gpos_pause (NULL);
 
-  for (unsigned int table_index = 0; table_index < 2; table_index++) {
-    hb_tag_t table_tag = table_tags[table_index];
-
+  for (unsigned int table_index = 0; table_index < 2; table_index++)
+  {
     /* Collect lookup indices for features */
 
-    unsigned int required_feature_index;
-    if (hb_ot_layout_language_get_required_feature_index (face,
-                                                          table_tag,
-                                                          script_index[table_index],
-                                                          language_index[table_index],
-                                                          &required_feature_index))
-      m.add_lookups (face, table_index, required_feature_index, 1, true);
-
     unsigned int stage_index = 0;
     unsigned int last_num_lookups = 0;
     for (unsigned stage = 0; stage < current_stage[table_index]; stage++)
     {
+      if (required_feature_index[table_index] != HB_OT_LAYOUT_NO_FEATURE_INDEX &&
+          required_feature_stage[table_index] == stage)
+        m.add_lookups (face, table_index,
+                       required_feature_index[table_index],
+                       1 /* mask */,
+                       true /* auto_zwj */);
+
       for (unsigned i = 0; i < m.features.len; i++)
         if (m.features[i].stage[table_index] == stage)
           m.add_lookups (face, table_index,
                          m.features[i].index[table_index],
                          m.features[i].mask,
                          m.features[i].auto_zwj);
 
       /* Sort lookups and merge duplicates */
       if (last_num_lookups < m.lookups[table_index].len)
       {
-        m.lookups[table_index].sort (last_num_lookups, m.lookups[table_index].len);
+        m.lookups[table_index].qsort (last_num_lookups, m.lookups[table_index].len);
 
         unsigned int j = last_num_lookups;
         for (unsigned int i = j + 1; i < m.lookups[table_index].len; i++)
           if (m.lookups[table_index][i].index != m.lookups[table_index][j].index)
             m.lookups[table_index][++j] = m.lookups[table_index][i];
           else
           {
             m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask;
             m.lookups[table_index][j].auto_zwj &= m.lookups[table_index][i].auto_zwj;
           }
         m.lookups[table_index].shrink (j + 1);
       }
 
       last_num_lookups = m.lookups[table_index].len;
 
       if (stage_index < stages[table_index].len && stages[table_index][stage_index].index == stage) {
         hb_ot_map_t::stage_map_t *stage_map = m.stages[table_index].push ();
         if (likely (stage_map)) {
           stage_map->last_lookup = last_num_lookups;
           stage_map->pause_func = stages[table_index][stage_index].pause_func;
         }
 
         stage_index++;
       }
     }
   }
 }