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

76 строки
1.6 KiB
Diff

commit dfec2c249915560cedd2b49326c6629ad8a0b0f2
Author: Jeff Muizelaar <jmuizelaar@mozilla.com>
Date: Tue Mar 2 16:01:41 2010 -0500
add a stash of cairo_t's
diff --git a/src/cairo.c b/src/cairo.c
index 3c9d892..4b27b83 100644
--- a/src/cairo.c
+++ b/src/cairo.c
@@ -119,7 +119,63 @@ _cairo_set_error (cairo_t *cr, cairo_status_t status)
_cairo_status_set_error (&cr->status, _cairo_error (status));
}
-#if HAS_ATOMIC_OPS
+#if defined(_MSC_VER)
+#pragma intrinsic(_BitScanForward)
+static __forceinline int
+ffs(int x)
+{
+ unsigned long i;
+
+ if (_BitScanForward(&i, x) != 0)
+ return i + 1;
+
+ return 0;
+}
+#endif
+
+
+#if CAIRO_NO_MUTEX
+/* We keep a small stash of contexts to reduce malloc pressure */
+#define CAIRO_STASH_SIZE 4
+static struct {
+ cairo_t pool[CAIRO_STASH_SIZE];
+ int occupied;
+} _context_stash;
+
+static cairo_t *
+_context_get (void)
+{
+ int avail, old, new;
+
+ old = _context_stash.occupied;
+ avail = ffs (~old) - 1;
+ if (avail >= CAIRO_STASH_SIZE)
+ return malloc (sizeof (cairo_t));
+
+ new = old | (1 << avail);
+ _context_stash.occupied = new;
+
+ return &_context_stash.pool[avail];
+}
+
+static void
+_context_put (cairo_t *cr)
+{
+ int old, new, avail;
+
+ if (cr < &_context_stash.pool[0] ||
+ cr >= &_context_stash.pool[CAIRO_STASH_SIZE])
+ {
+ free (cr);
+ return;
+ }
+
+ avail = ~(1 << (cr - &_context_stash.pool[0]));
+ old = _context_stash.occupied;
+ new = old & avail;
+ _context_stash.occupied = new;
+}
+#elif HAS_ATOMIC_OPS
/* We keep a small stash of contexts to reduce malloc pressure */
#define CAIRO_STASH_SIZE 4
static struct {