mesa st: Move logbase2 function to util/u_math.h

1 files changed, 18 insertions, 5 deletions

diff --git a/src/gallium/auxiliary/util/u_math.h b/src/gallium/auxiliary/util/u_math.h
index e5003af01d..30e6e2f6b3 100644
--- a/src/gallium/auxiliary/util/u_math.h
+++ b/src/gallium/auxiliary/util/u_math.h
@@ -216,23 +216,23 @@ util_fast_exp2(float x)
    int32_t ipart;
    float fpart, mpart;
    union fi epart;
-   
+
    if(x > 129.00000f)
       return 3.402823466e+38f;
-   
+
    if(x < -126.99999f)
       return 0.0f;
 
    ipart = (int32_t) x;
    fpart = x - (float) ipart;
-   
+
    /* same as
     *   epart.f = (float) (1 << ipart)
     * but faster and without integer overflow for ipart > 31 */
    epart.i = (ipart + 127 ) << 23;
-   
+
    mpart = pow2_table[POW2_TABLE_OFFSET + (int)(fpart * POW2_TABLE_SCALE)];
-   
+
    return epart.f * mpart;
 }
 
@@ -409,6 +409,19 @@ float_to_ubyte(float f)
 }
 
 
+/**
+ * Calc log base 2
+ */
+static INLINE unsigned
+util_logbase2(unsigned n)
+{
+   unsigned log2 = 0;
+   while (n >>= 1)
+      ++log2;
+   return log2;
+}
+
+
 
 #define CLAMP( X, MIN, MAX )  ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )