Update harfbuzz-ng to 0.9.14 from 0.9.10

third_party/harfbuzz-ng/src/hb-ot-shape-normalize.cc

 /*
  * Copyright © 2011,2012  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.
@@ skipping 174 matching lines @@
     if (!c->font->get_glyph (decomposed[i], 0, &glyphs[i]))
       return 0;
 
   for (i = 0; i < len; i++)
     output_char (c->buffer, decomposed[i], glyphs[i]);
 
   return len;
 }
 
 /* Returns true if recomposition may be benefitial. */
-static inline bool
+static inline void
 decompose_current_character (const hb_ot_shape_normalize_context_t *c, bool shortest)
 {
   hb_buffer_t * const buffer = c->buffer;
   hb_codepoint_t glyph;
-  unsigned int len = 1;
 
   /* Kind of a cute waterfall here... */
   if (shortest && c->font->get_glyph (buffer->cur().codepoint, 0, &glyph))
     next_char (buffer, glyph);
-  else if ((len = decompose (c, shortest, buffer->cur().codepoint)))
+  else if (decompose (c, shortest, buffer->cur().codepoint))
     skip_char (buffer);
   else if (!shortest && c->font->get_glyph (buffer->cur().codepoint, 0, &glyph))
     next_char (buffer, glyph);
-  else if ((len = decompose_compatibility (c, buffer->cur().codepoint)))
+  else if (decompose_compatibility (c, buffer->cur().codepoint))
     skip_char (buffer);
   else
     next_char (buffer, glyph); /* glyph is initialized in earlier branches. */
-
-  /*
-   * A recomposition would only be useful if we decomposed into at least three
-   * characters...
-   */
-  return len > 2;
 }
 
 static inline void
 handle_variation_selector_cluster (const hb_ot_shape_normalize_context_t *c, unsigned int end)
 {
   hb_buffer_t * const buffer = c->buffer;
   for (; buffer->idx < end - 1;) {
     if (unlikely (buffer->unicode->is_variation_selector (buffer->cur(+1).codepoint))) {
       /* The next two lines are some ugly lines... But work. */
       c->font->get_glyph (buffer->cur().codepoint, buffer->cur(+1).codepoint, &buffer->cur().glyph_index());
       buffer->replace_glyphs (2, 1, &buffer->cur().codepoint);
     } else {
       set_glyph (buffer->cur(), c->font);
       buffer->next_glyph ();
     }
   }
   if (likely (buffer->idx < end)) {
     set_glyph (buffer->cur(), c->font);
     buffer->next_glyph ();
   }
 }
 
 /* Returns true if recomposition may be benefitial. */
-static inline bool
+static inline void
 decompose_multi_char_cluster (const hb_ot_shape_normalize_context_t *c, unsigned int end)
 {
   hb_buffer_t * const buffer = c->buffer;
   /* TODO Currently if there's a variation-selector we give-up, it's just too hard. */
   for (unsigned int i = buffer->idx; i < end; i++)
     if (unlikely (buffer->unicode->is_variation_selector (buffer->info[i].codepoint))) {
       handle_variation_selector_cluster (c, end);
-      return false;
+      return;
     }
 
   while (buffer->idx < end)
     decompose_current_character (c, false);
-  /* We can be smarter here and only return true if there are at least two ccc!=0 marks.
-   * But does not matter. */
-  return true;
 }
 
-static inline bool
+static inline void
 decompose_cluster (const hb_ot_shape_normalize_context_t *c, bool short_circuit, unsigned int end)
 {
   if (likely (c->buffer->idx + 1 == end))
-    return decompose_current_character (c, short_circuit);
+    decompose_current_character (c, short_circuit);
   else
-    return decompose_multi_char_cluster (c, end);
+    decompose_multi_char_cluster (c, end);
 }
 
 
 static int
 compare_combining_class (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
 {
   unsigned int a = _hb_glyph_info_get_modified_combining_class (pa);
   unsigned int b = _hb_glyph_info_get_modified_combining_class (pb);
 
   return a < b ? -1 : a == b ? 0 : +1;
@@ skipping 12 matching lines @@
     plan,
     buffer,
     font,
     buffer->unicode,
     plan->shaper->decompose ? plan->shaper->decompose : decompose_unicode,
     plan->shaper->compose   ? plan->shaper->compose   : compose_unicode
   };
 
   bool short_circuit = mode != HB_OT_SHAPE_NORMALIZATION_MODE_DECOMPOSED &&
                        mode != HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT;
-  bool can_use_recompose = false;
   unsigned int count;
 
   /* We do a fairly straightforward yet custom normalization process in three
    * separate rounds: decompose, reorder, recompose (if desired).  Currently
    * this makes two buffer swaps.  We can make it faster by moving the last
    * two rounds into the inner loop for the first round, but it's more readable
    * this way. */
 
 
   /* First round, decompose */
 
   buffer->clear_output ();
   count = buffer->len;
   for (buffer->idx = 0; buffer->idx < count;)
   {
     unsigned int end;
     for (end = buffer->idx + 1; end < count; end++)
       if (buffer->cur().cluster != buffer->info[end].cluster)
         break;
 
-    can_use_recompose = decompose_cluster (&c, short_circuit, end) || can_use_recompose;
+    decompose_cluster (&c, short_circuit, end);
   }
   buffer->swap_buffers ();
 
 
-  if (mode != HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_FULL && !can_use_recompose)
-    return; /* Done! */
-
-
   /* Second round, reorder (inplace) */
 
   count = buffer->len;
   for (unsigned int i = 0; i < count; i++)
   {
     if (_hb_glyph_info_get_modified_combining_class (&buffer->info[i]) == 0)
       continue;
 
     unsigned int end;
     for (end = i + 1; end < count; end++)
@@ skipping 23 matching lines @@
    * ccc=0 chars with their previous Starter. */
 
   buffer->clear_output ();
   count = buffer->len;
   unsigned int starter = 0;
   buffer->next_glyph ();
   while (buffer->idx < count)
   {
     hb_codepoint_t composed, glyph;
     if (/* If mode is NOT COMPOSED_FULL (ie. it's COMPOSED_DIACRITICS), we don't try to
-         * compose a CCC=0 character with it's preceding starter. */
+         * compose a non-mark character with it's preceding starter.  This is just an
+         * optimization to avoid trying to compose every two neighboring glyphs in most
+         * scripts. */
         (mode == HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_FULL ||
-         _hb_glyph_info_get_modified_combining_class (&buffer->cur()) != 0) &&
+         HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&buffer->cur()))) &&
         /* If there's anything between the starter and this char, they should have CCC
          * smaller than this character's. */
         (starter == buffer->out_len - 1 ||
          _hb_glyph_info_get_modified_combining_class (&buffer->prev()) < _hb_glyph_info_get_modified_combining_class (&buffer->cur())) &&
         /* And compose. */
         c.compose (&c,
                    buffer->out_info[starter].codepoint,
                    buffer->cur().codepoint,
                    &composed) &&
         /* And the font has glyph for the composite. */
@@ skipping 14 matching lines @@
 
     /* Blocked, or doesn't compose. */
     buffer->next_glyph ();
 
     if (_hb_glyph_info_get_modified_combining_class (&buffer->prev()) == 0)
       starter = buffer->out_len - 1;
   }
   buffer->swap_buffers ();
 
 }