}
-/**
- * Find last bit set in a word. The least significant bit is 1.
- * Return 0 if no bits are set.
- */
-static inline unsigned
-util_last_bit(unsigned u)
-{
-#if defined(HAVE___BUILTIN_CLZ)
- return u == 0 ? 0 : 32 - __builtin_clz(u);
-#else
- unsigned r = 0;
- while (u) {
- r++;
- u >>= 1;
- }
- return r;
-#endif
-}
-
-/**
- * Find last bit set in a word. The least significant bit is 1.
- * Return 0 if no bits are set.
- */
-static inline unsigned
-util_last_bit64(uint64_t u)
-{
-#if defined(HAVE___BUILTIN_CLZLL)
- return u == 0 ? 0 : 64 - __builtin_clzll(u);
-#else
- unsigned r = 0;
- while (u) {
- r++;
- u >>= 1;
- }
- return r;
-#endif
-}
-
-/**
- * Find last bit in a word that does not match the sign bit. The least
- * significant bit is 1.
- * Return 0 if no bits are set.
- */
-static inline unsigned
-util_last_bit_signed(int i)
-{
- if (i >= 0)
- return util_last_bit(i);
- else
- return util_last_bit(~(unsigned)i);
-}
-
-/* Returns a bitfield in which the first count bits starting at start are
- * set.
- */
-static inline unsigned
-u_bit_consecutive(unsigned start, unsigned count)
-{
- assert(start + count <= 32);
- if (count == 32)
- return ~0;
- return ((1u << count) - 1) << start;
-}
-
/**
* Return float bits.
*/
#endif
}
+/**
+ * Returns the ceiling of log n base 2, and 0 when n == 0. Equivalently,
+ * returns the smallest x such that n <= 2**x.
+ */
+static inline unsigned
+util_logbase2_ceil(unsigned n)
+{
+ if (n <= 1)
+ return 0;
+
+ return 1 + util_logbase2(n - 1);
+}
/**
* Returns the smallest power of two >= x