Commit 6044dfc3 authored by Neil Roberts's avatar Neil Roberts Committed by Benjamin Otte

bitmask: Don't allocate memory for small bitmasks

Code taken more or less verbatim from CoglBitmask.
parent 27eb83a4
......@@ -31,6 +31,15 @@ struct _GtkBitmask {
VALUE_TYPE data[1];
};
#define ENSURE_ALLOCATED(mask, heap_mask) G_STMT_START { \
if (!_gtk_bitmask_is_allocated (mask)) \
{ \
heap_mask.data[0] = _gtk_bitmask_to_bits (mask); \
heap_mask.len = heap_mask.data[0] ? 1 : 0; \
mask = &heap_mask; \
} \
} G_STMT_END
static GtkBitmask *
gtk_allocated_bitmask_resize (GtkBitmask *mask,
gsize size) G_GNUC_WARN_UNUSED_RESULT;
......@@ -40,7 +49,7 @@ gtk_allocated_bitmask_resize (GtkBitmask *mask,
{
gsize i;
mask = g_realloc (mask, sizeof (GtkBitmask) + sizeof(VALUE_TYPE) * (MAX (size, 1) - 1));
mask = g_realloc (mask, sizeof (GtkBitmask) + sizeof(VALUE_TYPE) * (size - 1));
for (i = mask->len; i < size; i++)
mask->data[i] = 0;
......@@ -50,10 +59,25 @@ gtk_allocated_bitmask_resize (GtkBitmask *mask,
return mask;
}
GtkBitmask *
_gtk_allocated_bitmask_new (void)
static GtkBitmask *
gtk_allocated_bitmask_new_for_bits (gsize bits)
{
GtkBitmask *mask;
mask = g_malloc (sizeof (GtkBitmask));
mask->len = bits ? 1 : 0;
mask->data[0] = bits;
return mask;
}
static GtkBitmask *
gtk_bitmask_ensure_allocated (GtkBitmask *mask)
{
return g_malloc0 (sizeof (GtkBitmask));
if (_gtk_bitmask_is_allocated (mask))
return mask;
else
return gtk_allocated_bitmask_new_for_bits (_gtk_bitmask_to_bits (mask));
}
GtkBitmask *
......@@ -63,7 +87,7 @@ _gtk_allocated_bitmask_copy (const GtkBitmask *mask)
g_return_val_if_fail (mask != NULL, NULL);
copy = _gtk_allocated_bitmask_new ();
copy = gtk_allocated_bitmask_new_for_bits (0);
return _gtk_allocated_bitmask_union (copy, mask);
}
......@@ -80,11 +104,14 @@ void
_gtk_allocated_bitmask_print (const GtkBitmask *mask,
GString *string)
{
GtkBitmask mask_allocated;
int i;
g_return_if_fail (mask != NULL);
g_return_if_fail (string != NULL);
ENSURE_ALLOCATED (mask, mask_allocated);
for (i = mask->len * VALUE_SIZE_BITS - 1; i >= 0; i--)
{
if (_gtk_allocated_bitmask_get (mask, i))
......@@ -103,16 +130,6 @@ _gtk_allocated_bitmask_print (const GtkBitmask *mask,
}
}
char *
_gtk_allocated_bitmask_to_string (const GtkBitmask *mask)
{
GString *string;
string = g_string_new (NULL);
_gtk_allocated_bitmask_print (mask, string);
return g_string_free (string, FALSE);
}
/* NB: Call this function whenever the
* array might have become too large.
* _gtk_allocated_bitmask_is_empty() depends on this.
......@@ -130,6 +147,14 @@ gtk_allocated_bitmask_shrink (GtkBitmask *mask)
break;
}
if (i == 0 ||
(i == 1 && mask->data[0] < VALUE_BIT (GTK_BITMASK_N_DIRECT_BITS)))
{
GtkBitmask *result = _gtk_bitmask_from_bits (i == 0 ? 0 : mask->data[0]);
_gtk_allocated_bitmask_free (mask);
return result;
}
return gtk_allocated_bitmask_resize (mask, i);
}
......@@ -137,11 +162,15 @@ GtkBitmask *
_gtk_allocated_bitmask_intersect (GtkBitmask *mask,
const GtkBitmask *other)
{
GtkBitmask other_allocated;
guint i;
g_return_val_if_fail (mask != NULL, NULL);
g_return_val_if_fail (other != NULL, NULL);
mask = gtk_bitmask_ensure_allocated (mask);
ENSURE_ALLOCATED (other, other_allocated);
mask = gtk_allocated_bitmask_resize (mask, MIN (mask->len, other->len));
for (i = 0; i < mask->len; i++)
{
......@@ -155,11 +184,15 @@ GtkBitmask *
_gtk_allocated_bitmask_union (GtkBitmask *mask,
const GtkBitmask *other)
{
GtkBitmask other_allocated;
guint i;
g_return_val_if_fail (mask != NULL, NULL);
g_return_val_if_fail (other != NULL, NULL);
mask = gtk_bitmask_ensure_allocated (mask);
ENSURE_ALLOCATED (other, other_allocated);
mask = gtk_allocated_bitmask_resize (mask, MAX (mask->len, other->len));
for (i = 0; i < other->len; i++)
{
......@@ -173,11 +206,15 @@ GtkBitmask *
_gtk_allocated_bitmask_subtract (GtkBitmask *mask,
const GtkBitmask *other)
{
GtkBitmask other_allocated;
guint i;
g_return_val_if_fail (mask != NULL, NULL);
g_return_val_if_fail (other != NULL, NULL);
mask = gtk_bitmask_ensure_allocated (mask);
ENSURE_ALLOCATED (other, other_allocated);
for (i = 0; i < other->len; i++)
{
mask->data[i] |= ~other->data[i];
......@@ -220,6 +257,7 @@ _gtk_allocated_bitmask_set (GtkBitmask *mask,
g_return_val_if_fail (mask != NULL, NULL);
mask = gtk_bitmask_ensure_allocated (mask);
gtk_allocated_bitmask_indexes (index_, &array_index, &bit_index);
if (value)
......@@ -251,22 +289,15 @@ _gtk_allocated_bitmask_invert_range (GtkBitmask *mask,
g_return_val_if_fail (mask != NULL, NULL);
g_return_val_if_fail (start < end, NULL);
/* I CAN HAS SPEEDUP? */
mask = gtk_bitmask_ensure_allocated (mask);
/* I CAN HAS SPEEDUP? */
for (i = start; i < end; i++)
mask = _gtk_allocated_bitmask_set (mask, i, !_gtk_allocated_bitmask_get (mask, i));
return mask;
}
gboolean
_gtk_allocated_bitmask_is_empty (const GtkBitmask *mask)
{
g_return_val_if_fail (mask != NULL, FALSE);
return mask->len == 0;
}
gboolean
_gtk_allocated_bitmask_equals (const GtkBitmask *mask,
const GtkBitmask *other)
......@@ -292,11 +323,15 @@ gboolean
_gtk_allocated_bitmask_intersects (const GtkBitmask *mask,
const GtkBitmask *other)
{
GtkBitmask mask_allocated, other_allocated;
int i;
g_return_val_if_fail (mask != NULL, FALSE);
g_return_val_if_fail (other != NULL, FALSE);
ENSURE_ALLOCATED (mask, mask_allocated);
ENSURE_ALLOCATED (other, other_allocated);
for (i = MIN (mask->len, other->len) - 1; i >= 0; i--)
{
if (mask->data[i] & other->data[i])
......
......@@ -27,12 +27,21 @@ G_BEGIN_DECLS
typedef struct _GtkBitmask GtkBitmask;
#define _gtk_bitmask_to_bits(mask) \
(GPOINTER_TO_SIZE (mask) >> ((gsize) 1))
#define _gtk_bitmask_from_bits(bits) \
GSIZE_TO_POINTER ((((gsize) (bits)) << 1) | 1)
#define _gtk_bitmask_is_allocated(mask) \
(!(GPOINTER_TO_SIZE (mask) & 1))
#define GTK_BITMASK_N_DIRECT_BITS (sizeof (gsize) * 8 - 1)
GtkBitmask * _gtk_allocated_bitmask_new (void);
GtkBitmask * _gtk_allocated_bitmask_copy (const GtkBitmask *mask);
void _gtk_allocated_bitmask_free (GtkBitmask *mask);
char * _gtk_allocated_bitmask_to_string (const GtkBitmask *mask);
void _gtk_allocated_bitmask_print (const GtkBitmask *mask,
GString *string);
......@@ -53,7 +62,6 @@ GtkBitmask * _gtk_allocated_bitmask_invert_range (GtkBitmask *mask
guint start,
guint end) G_GNUC_WARN_UNUSED_RESULT;
gboolean _gtk_allocated_bitmask_is_empty (const GtkBitmask *mask);
gboolean _gtk_allocated_bitmask_equals (const GtkBitmask *mask,
const GtkBitmask *other);
gboolean _gtk_allocated_bitmask_intersects (const GtkBitmask *mask,
......
......@@ -23,25 +23,33 @@
static inline GtkBitmask *
_gtk_bitmask_new (void)
{
return _gtk_allocated_bitmask_new ();
return _gtk_bitmask_from_bits (0);
}
static inline GtkBitmask *
_gtk_bitmask_copy (const GtkBitmask *mask)
{
if (_gtk_bitmask_is_allocated (mask))
return _gtk_allocated_bitmask_copy (mask);
else
return (GtkBitmask *) mask;
}
static inline void
_gtk_bitmask_free (GtkBitmask *mask)
{
if (_gtk_bitmask_is_allocated (mask))
return _gtk_allocated_bitmask_free (mask);
}
static inline char *
_gtk_bitmask_to_string (const GtkBitmask *mask)
{
return _gtk_allocated_bitmask_to_string (mask);
GString *string;
string = g_string_new (NULL);
_gtk_allocated_bitmask_print (mask, string);
return g_string_free (string, FALSE);
}
static inline void
......@@ -62,7 +70,12 @@ static inline GtkBitmask *
_gtk_bitmask_union (GtkBitmask *mask,
const GtkBitmask *other)
{
if (_gtk_bitmask_is_allocated (mask) ||
_gtk_bitmask_is_allocated (other))
return _gtk_allocated_bitmask_union (mask, other);
else
return _gtk_bitmask_from_bits (_gtk_bitmask_to_bits (mask)
| _gtk_bitmask_to_bits (other));
}
static inline GtkBitmask *
......@@ -76,7 +89,12 @@ static inline gboolean
_gtk_bitmask_get (const GtkBitmask *mask,
guint index_)
{
if (_gtk_bitmask_is_allocated (mask))
return _gtk_allocated_bitmask_get (mask, index_);
else
return index_ < GTK_BITMASK_N_DIRECT_BITS
? !!(_gtk_bitmask_to_bits (mask) & (((size_t) 1) << index_))
: FALSE;
}
static inline GtkBitmask *
......@@ -84,7 +102,22 @@ _gtk_bitmask_set (GtkBitmask *mask,
guint index_,
gboolean value)
{
if (_gtk_bitmask_is_allocated (mask) ||
(index_ >= GTK_BITMASK_N_DIRECT_BITS && value))
return _gtk_allocated_bitmask_set (mask, index_, value);
else if (index_ < GTK_BITMASK_N_DIRECT_BITS)
{
gsize bits = _gtk_bitmask_to_bits (mask);
if (value)
bits |= ((size_t) 1) << index_;
else
bits &= ~(((size_t) 1) << index_);
return _gtk_bitmask_from_bits (bits);
}
else
return mask;
}
static inline GtkBitmask *
......@@ -92,19 +125,34 @@ _gtk_bitmask_invert_range (GtkBitmask *mask,
guint start,
guint end)
{
if (_gtk_bitmask_is_allocated (mask) ||
(end > GTK_BITMASK_N_DIRECT_BITS))
return _gtk_allocated_bitmask_invert_range (mask, start, end);
else
{
size_t invert = (((size_t) 1) << end) - (((size_t) 1) << start);
return _gtk_bitmask_from_bits (_gtk_bitmask_to_bits (mask) ^ invert);
}
}
static inline gboolean
_gtk_bitmask_is_empty (const GtkBitmask *mask)
{
return _gtk_allocated_bitmask_is_empty (mask);
return mask == _gtk_bitmask_from_bits (0);
}
static inline gboolean
_gtk_bitmask_equals (const GtkBitmask *mask,
const GtkBitmask *other)
{
if (mask == other)
return TRUE;
if (!_gtk_bitmask_is_allocated (mask) ||
!_gtk_bitmask_is_allocated (other))
return FALSE;
return _gtk_allocated_bitmask_equals (mask, other);
}
......@@ -112,5 +160,9 @@ static inline gboolean
_gtk_bitmask_intersects (const GtkBitmask *mask,
const GtkBitmask *other)
{
if (!_gtk_bitmask_is_allocated (mask) ||
!_gtk_bitmask_is_allocated (other))
return _gtk_allocated_bitmask_intersects (mask, other);
else
return _gtk_bitmask_to_bits (mask) & _gtk_bitmask_to_bits (other);
}
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