[HB] Improve buffer. Don't dup out buffer unless out is longer than in
That is, we work in-place even for ligatures now.
diff --git a/src/hb-buffer.c b/src/hb-buffer.c
index 0fec18c..308fb70 100644
--- a/src/hb-buffer.c
+++ b/src/hb-buffer.c
@@ -36,24 +36,16 @@
*
* As an optimization, both in_string and out_string may point to the
* same piece of memory, which is owned by in_string. This remains the
- * case as long as:
+ * case as long as out_length doesn't exceed in_length at any time.
+ * In that case, swap() is no-op and the glyph operations operate mostly
+ * in-place.
*
- * - copy_glyph() is called
- * - replace_glyph() is called with inplace=TRUE
- * - add_output_glyph() and add_output_glyphs() are not called
- *
- * In that case swap(), and copy_glyph(), and replace_glyph() are all
- * mostly no-op.
- *
- * As soon an add_output_glyph[s]() or replace_glyph() with inplace=FALSE is
- * called, out_string is moved over to an alternate buffer (alt_string), and
- * its current contents (out_length entries) are copied to the alt buffer.
- * This should all remain transparent to the user. swap() then switches
- * in_string and alt_string. alt_string is not allocated until its needed,
- * but after that it's grown with in_string unconditionally.
- *
- * The buffer->separate_out boolean keeps status of whether out_string points
- * to in_string (FALSE) or alt_string (TRUE).
+ * As soon as out_string gets longer than in_string, out_string is moved over
+ * to an alternate buffer (alt_string), and its current contents (out_length
+ * entries) are copied to the alt buffer. This should all remain transparent
+ * to the user. swap() then switches in_string and alt_string. alt_string is
+ * not allocated until its needed, but after that it's grown with in_string
+ * unconditionally.
*/
/* XXX err handling */
@@ -66,52 +58,47 @@
unsigned int new_allocated = buffer->allocated;
if (size > new_allocated)
+ {
+ while (size > new_allocated)
+ new_allocated += (new_allocated >> 1) + 8;
+
+ if (buffer->positions)
+ buffer->positions = realloc (buffer->positions, new_allocated * sizeof (buffer->positions[0]));
+
+ buffer->in_string = realloc (buffer->in_string, new_allocated * sizeof (buffer->in_string[0]));
+
+ if (buffer->out_string != buffer->in_string)
{
- while (size > new_allocated)
- new_allocated += (new_allocated >> 1) + 8;
-
- if (buffer->positions)
- buffer->positions = realloc (buffer->positions, new_allocated * sizeof (buffer->positions[0]));
-
- buffer->in_string = realloc (buffer->in_string, new_allocated * sizeof (buffer->in_string[0]));
-
- if (buffer->separate_out)
- {
- buffer->alt_string = realloc (buffer->alt_string, new_allocated * sizeof (buffer->alt_string[0]));
- buffer->out_string = buffer->alt_string;
- }
- else
- {
- buffer->out_string = buffer->in_string;
-
- if (buffer->alt_string)
- {
- free (buffer->alt_string);
- buffer->alt_string = NULL;
- }
- }
-
- buffer->allocated = new_allocated;
+ buffer->alt_string = realloc (buffer->alt_string, new_allocated * sizeof (buffer->alt_string[0]));
+ buffer->out_string = buffer->alt_string;
}
-}
+ else
+ {
+ buffer->out_string = buffer->in_string;
-static void
-hb_buffer_duplicate_out_buffer (hb_buffer_t *buffer)
-{
- if (!buffer->alt_string)
- buffer->alt_string = malloc (buffer->allocated * sizeof (buffer->alt_string[0]));
+ if (buffer->alt_string)
+ {
+ free (buffer->alt_string);
+ buffer->alt_string = NULL;
+ }
+ }
- buffer->out_string = buffer->alt_string;
- memcpy (buffer->out_string, buffer->in_string, buffer->out_length * sizeof (buffer->out_string[0]));
- buffer->separate_out = TRUE;
+ buffer->allocated = new_allocated;
+ }
}
static void
hb_buffer_ensure_separate (hb_buffer_t *buffer, unsigned int size)
{
hb_buffer_ensure (buffer, size);
- if ( !buffer->separate_out )
- hb_buffer_duplicate_out_buffer (buffer);
+ if (buffer->out_string == buffer->in_string)
+ {
+ if (!buffer->alt_string)
+ buffer->alt_string = malloc (buffer->allocated * sizeof (buffer->alt_string[0]));
+
+ buffer->out_string = buffer->alt_string;
+ memcpy (buffer->out_string, buffer->in_string, buffer->out_length * sizeof (buffer->out_string[0]));
+ }
}
/* Public API */
@@ -152,7 +139,6 @@
buffer->in_pos = 0;
buffer->out_pos = 0;
buffer->out_string = buffer->in_string;
- buffer->separate_out = FALSE;
buffer->max_lig_id = 0;
}
@@ -185,7 +171,6 @@
buffer->out_length = 0;
buffer->out_pos = 0;
buffer->out_string = buffer->in_string;
- buffer->separate_out = FALSE;
}
HB_INTERNAL void
@@ -207,14 +192,14 @@
{
unsigned int tmp;
- if (buffer->separate_out)
- {
- hb_glyph_info_t *tmp_string;
- tmp_string = buffer->in_string;
- buffer->in_string = buffer->out_string;
- buffer->out_string = tmp_string;
- buffer->alt_string = buffer->out_string;
- }
+ if (buffer->out_string != buffer->in_string)
+ {
+ hb_glyph_info_t *tmp_string;
+ tmp_string = buffer->in_string;
+ buffer->in_string = buffer->out_string;
+ buffer->out_string = tmp_string;
+ buffer->alt_string = buffer->out_string;
+ }
tmp = buffer->in_length;
buffer->in_length = buffer->out_length;
@@ -256,7 +241,11 @@
unsigned int properties;
unsigned int cluster;
- hb_buffer_ensure_separate (buffer, buffer->out_pos + num_out);
+ if (buffer->out_string == buffer->in_string &&
+ buffer->out_pos + num_out > buffer->in_pos + num_in)
+ {
+ hb_buffer_ensure_separate (buffer, buffer->out_pos + num_out);
+ }
properties = buffer->in_string[buffer->in_pos].properties;
cluster = buffer->in_string[buffer->in_pos].cluster;
@@ -268,7 +257,6 @@
for (i = 0; i < num_out; i++)
{
hb_glyph_info_t *info = &buffer->out_string[buffer->out_pos + i];
-
info->gindex = hb_be_uint16_t (glyph_data_be[i]);
info->properties = properties;
info->cluster = cluster;
@@ -279,7 +267,6 @@
buffer->in_pos += num_in;
buffer->out_pos += num_out;
-
buffer->out_length = buffer->out_pos;
}
@@ -292,11 +279,15 @@
{
hb_glyph_info_t *info;
- hb_buffer_ensure_separate (buffer, buffer->out_pos + 1);
+ if (buffer->out_string != buffer->in_string)
+ {
+ hb_buffer_ensure (buffer, buffer->out_pos + 1);
+ buffer->out_string[buffer->out_pos] = buffer->in_string[buffer->in_pos];
+ }
+ else if (buffer->out_pos != buffer->in_pos)
+ buffer->out_string[buffer->out_pos] = buffer->in_string[buffer->in_pos];
info = &buffer->out_string[buffer->out_pos];
- *info = buffer->in_string[buffer->in_pos];
-
info->gindex = glyph_index;
if (component != 0xFFFF)
info->component = component;
@@ -306,19 +297,19 @@
buffer->in_pos++;
buffer->out_pos++;
-
buffer->out_length = buffer->out_pos;
}
HB_INTERNAL void
_hb_buffer_next_glyph (hb_buffer_t *buffer)
{
- if (buffer->separate_out)
- {
- hb_buffer_ensure (buffer, buffer->out_pos + 1);
-
- buffer->out_string[buffer->out_pos] = buffer->in_string[buffer->in_pos];
- }
+ if (buffer->out_string != buffer->in_string)
+ {
+ hb_buffer_ensure (buffer, buffer->out_pos + 1);
+ buffer->out_string[buffer->out_pos] = buffer->in_string[buffer->in_pos];
+ }
+ else if (buffer->out_pos != buffer->in_pos)
+ buffer->out_string[buffer->out_pos] = buffer->in_string[buffer->in_pos];
buffer->in_pos++;
buffer->out_pos++;
@@ -329,18 +320,7 @@
_hb_buffer_replace_glyph (hb_buffer_t *buffer,
hb_codepoint_t glyph_index)
{
- if (!buffer->separate_out)
- {
- buffer->out_string[buffer->out_pos].gindex = glyph_index;
-
- buffer->in_pos++;
- buffer->out_pos++;
- buffer->out_length = buffer->out_pos;
- }
- else
- {
- return _hb_buffer_add_output_glyph (buffer, glyph_index, 0xFFFF, 0xFFFF);
- }
+ _hb_buffer_add_output_glyph (buffer, glyph_index, 0xFFFF, 0xFFFF);
}
HB_INTERNAL unsigned short
