gfx/cairo/add-a-stash-of-cairo_t-s.patch

   1 commit dfec2c249915560cedd2b49326c6629ad8a0b0f2
   2 Author: Jeff Muizelaar <jmuizelaar@mozilla.com>
   3 Date:   Tue Mar 2 16:01:41 2010 -0500
   4
   5     add a stash of cairo_t's
   6
   7 diff --git a/src/cairo.c b/src/cairo.c
   8 index 3c9d892..4b27b83 100644
   9 --- a/src/cairo.c
  10 +++ b/src/cairo.c
  11 @@ -119,7 +119,63 @@ _cairo_set_error (cairo_t *cr, cairo_status_t status)
  12      _cairo_status_set_error (&cr->status, _cairo_error (status));
  13  }
  14
  15 -#if HAS_ATOMIC_OPS
  16 +#if defined(_MSC_VER)
  17 +#pragma intrinsic(_BitScanForward)
  18 +static __forceinline int
  19 +ffs(int x)
  20 +{
  21 +    unsigned long i;
  22 +
  23 +    if (_BitScanForward(&i, x) != 0)
  24 +       return i + 1;
  25 +
  26 +    return 0;
  27 +}
  28 +#endif
  29 +
  30 +
  31 +#if CAIRO_NO_MUTEX
  32 +/* We keep a small stash of contexts to reduce malloc pressure */
  33 +#define CAIRO_STASH_SIZE 4
  34 +static struct {
  35 +    cairo_t pool[CAIRO_STASH_SIZE];
  36 +    int occupied;
  37 +} _context_stash;
  38 +
  39 +static cairo_t *
  40 +_context_get (void)
  41 +{
  42 +    int avail, old, new;
  43 +
  44 +    old = _context_stash.occupied;
  45 +    avail = ffs (~old) - 1;
  46 +    if (avail >= CAIRO_STASH_SIZE)
  47 +       return malloc (sizeof (cairo_t));
  48 +
  49 +    new = old | (1 << avail);
  50 +    _context_stash.occupied = new;
  51 +
  52 +    return &_context_stash.pool[avail];
  53 +}
  54 +
  55 +static void
  56 +_context_put (cairo_t *cr)
  57 +{
  58 +    int old, new, avail;
  59 +
  60 +    if (cr < &_context_stash.pool[0] ||
  61 +       cr >= &_context_stash.pool[CAIRO_STASH_SIZE])
  62 +    {
  63 +       free (cr);
  64 +       return;
  65 +    }
  66 +
  67 +    avail = ~(1 << (cr - &_context_stash.pool[0]));
  68 +    old = _context_stash.occupied;
  69 +    new = old & avail;
  70 +    _context_stash.occupied = new;
  71 +}
  72 +#elif HAS_ATOMIC_OPS
  73  /* We keep a small stash of contexts to reduce malloc pressure */
  74  #define CAIRO_STASH_SIZE 4
  75  static struct {