diff options
| author | José Fonseca <[email protected]> | 2009-08-29 09:15:10 +0100 |
|---|---|---|
| committer | José Fonseca <[email protected]> | 2009-08-29 09:21:42 +0100 |
| commit | fdb3e75f7e796d88c8e3cd478e2830754116baf0 (patch) | |
| tree | 650057f530b03a6a20c3cd6fdbd4080735b5cfa6 /src/gallium/auxiliary | |
| parent | c40eddd294abfe8af3619d08ccd7e9c8f1660fcb (diff) | |
util: Add util_unsigned_logbase2.
Cherry picked from Keith's commit f911c3b9897b90132c8621a72bfeb824eb3b01e5.
Diffstat (limited to 'src/gallium/auxiliary')
| -rw-r--r-- | src/gallium/auxiliary/util/u_math.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/util/u_math.h b/src/gallium/auxiliary/util/u_math.h index 57410e78b02..b0807c13392 100644 --- a/src/gallium/auxiliary/util/u_math.h +++ b/src/gallium/auxiliary/util/u_math.h @@ -375,6 +375,18 @@ unsigned ffs( unsigned u ) #endif +/* Could also binary search for the highest bit. + */ +static INLINE unsigned +util_unsigned_logbase2(unsigned n) +{ + unsigned log2 = 0; + while (n >>= 1) + ++log2; + return log2; +} + + /** * Return float bits. */ |