util: Utility function to check if a number is a power of two.

diff --git a/src/gallium/auxiliary/util/u_math.h b/src/gallium/auxiliary/util/u_math.h
index 4c6c2bc00e1ed0993ac7de7c2fb612876ed0645f..b12c97dfb4da6043dcda8d64b8a7d7532789e934 100644 (file)
--- a/src/gallium/auxiliary/util/u_math.h
+++ b/src/gallium/auxiliary/util/u_math.h
@@ -340,6 +340,16 @@ util_is_inf_or_nan(float x)
 }
 
 
+/**
+ * Test whether x is a power of two.
+ */
+static INLINE boolean
+util_is_pot(unsigned x)
+{
+   return (x & (x - 1)) == 0;
+}
+
+
 /**
  * Find first bit set in word.  Least significant bit is 1.
  * Return 0 if no bits set.