+static inline
+uint32_t bitcount(uint32_t bits)
+{
+ bits = (bits & 0x55555555) + (bits >> 1 & 0x55555555);
+ bits = (bits & 0x33333333) + (bits >> 2 & 0x33333333);
+ bits = (bits & 0x0f0f0f0f) + (bits >> 4 & 0x0f0f0f0f);
+ bits = (bits & 0x00ff00ff) + (bits >> 8 & 0x00ff00ff);
+ return (bits & 0x0000ffff) + (bits >>16 & 0x0000ffff);
+}