Roll harfbuzz-ng to 1.0.5

third_party/harfbuzz-ng/src/hb-ot-shape-complex-indic.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 994 matching lines @@
   }
 
 
   {
     /* Use syllable() for sort accounting temporarily. */
     unsigned int syllable = info[start].syllable();
     for (unsigned int i = start; i < end; i++)
       info[i].syllable() = i - start;
 
     /* Sit tight, rock 'n roll! */
-    hb_bubble_sort (info + start, end - start, compare_indic_order);
+    hb_stable_sort (info + start, end - start, compare_indic_order);
     /* Find base again */
     base = end;
     for (unsigned int i = start; i < end; i++)
       if (info[i].indic_position() == POS_BASE_C)
       {
         base = i;
         break;
       }
     /* Things are out-of-control for post base positions, they may shuffle
      * around like crazy.  In old-spec mode, we move halants around, so in
      * that case merge all clusters after base.  Otherwise, check the sort
      * order and merge as needed.
-     * For pre-base stuff, we handle cluster issues in final reordering. */
+     * For pre-base stuff, we handle cluster issues in final reordering.
+     *
+     * We could use buffer->sort() for this, if there was no special
+     * reordering of pre-base stuff happening later...
+     */
     if (indic_plan->is_old_spec || end - base > 127)
       buffer->merge_clusters (base, end);
     else
     {
       /* Note!  syllable() is a one-byte field. */
       for (unsigned int i = base; i < end; i++)
         if (info[i].syllable() != 255)
         {
           unsigned int max = i;
           unsigned int j = start + info[i].syllable();
@@ skipping 358 matching lines @@
         new_pos = start; /* No move. */
     }
 
     if (start < new_pos && info[new_pos].indic_position () != POS_PRE_M)
     {
       /* Now go see if there's actually any matras... */
       for (unsigned int i = new_pos; i > start; i--)
         if (info[i - 1].indic_position () == POS_PRE_M)
         {
           unsigned int old_pos = i - 1;
+          if (old_pos < base && base <= new_pos) /* Shouldn't actually happen. */
+            base--;
+
           hb_glyph_info_t tmp = info[old_pos];
           memmove (&info[old_pos], &info[old_pos + 1], (new_pos - old_pos) * sizeof (info[0]));
           info[new_pos] = tmp;
-          if (old_pos < base && base <= new_pos) /* Shouldn't actually happen. */
-            base--;
+
+          /* Note: this merge_clusters() is intentionally *after* the reordering.
+           * Indic matra reordering is special and tricky... */
           buffer->merge_clusters (new_pos, MIN (end, base + 1));
+
           new_pos--;
         }
     } else {
       for (unsigned int i = start; i < base; i++)
         if (info[i].indic_position () == POS_PRE_M) {
           buffer->merge_clusters (i, MIN (end, base + 1));
           break;
         }
     }
   }
@@ skipping 132 matching lines @@
           if (info[i].indic_category() == OT_M) {
             /* Ok, got it. */
             new_reph_pos--;
           }
       }
       goto reph_move;
     }
 
     reph_move:
     {
+      /* Move */
       buffer->merge_clusters (start, new_reph_pos + 1);
-
-      /* Move */
       hb_glyph_info_t reph = info[start];
       memmove (&info[start], &info[start + 1], (new_reph_pos - start) * sizeof (info[0]));
       info[new_reph_pos] = reph;
+
       if (start < base && base <= new_reph_pos)
         base--;
     }
   }
 
 
   /*   o Reorder pre-base reordering consonants:
    *
    *     If a pre-base reordering consonant is found, reorder it according to
    *     the following rules:
@@ skipping 52 matching lines @@
 
           if (new_pos > start && is_halant_or_coeng (info[new_pos - 1]))
           {
             /* -> If ZWJ or ZWNJ follow this halant, position is moved after it. */
             if (new_pos < end && is_joiner (info[new_pos]))
               new_pos++;
           }
 
           {
             unsigned int old_pos = i;
+
             buffer->merge_clusters (new_pos, old_pos + 1);
             hb_glyph_info_t tmp = info[old_pos];
             memmove (&info[new_pos + 1], &info[new_pos], (old_pos - new_pos) * sizeof (info[0]));
             info[new_pos] = tmp;
+
             if (new_pos <= base && base < old_pos)
               base++;
           }
         }
 
         break;
       }
   }
 
 
@@ skipping 166 matching lines @@
   data_create_indic,
   data_destroy_indic,
   NULL, /* preprocess_text */
   HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT,
   decompose_indic,
   compose_indic,
   setup_masks_indic,
   HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE,
   false, /* fallback_position */
 };