diff options
Diffstat (limited to 'cogl/cogl-util.h')
| -rw-r--r-- | cogl/cogl-util.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/cogl/cogl-util.h b/cogl/cogl-util.h index 1f3d2663..6e02ad7d 100644 --- a/cogl/cogl-util.h +++ b/cogl/cogl-util.h @@ -124,6 +124,7 @@ _cogl_util_one_at_a_time_mix (unsigned int hash); #if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4) #define COGL_UTIL_HAVE_BUILTIN_FFSL #define COGL_UTIL_HAVE_BUILTIN_POPCOUNTL +#define COGL_UTIL_HAVE_BUILTIN_CLZ #endif /* The 'ffs' function is part of C99 so it isn't always available */ @@ -148,6 +149,24 @@ int _cogl_util_ffsl_wrapper (long int num); #endif /* COGL_UTIL_HAVE_BUILTIN_FFSL */ +static inline unsigned int +_cogl_util_fls (unsigned int n) +{ +#ifdef COGL_UTIL_HAVE_BUILTIN_CLZ + return n == 0 ? 0 : sizeof (unsigned int) * 8 - __builtin_clz (n); +#else + unsigned int v = 1; + + if (n == 0) + return 0; + + while (n >>= 1) + v++; + + return v; +#endif +} + #ifdef COGL_UTIL_HAVE_BUILTIN_POPCOUNTL #define _cogl_util_popcountl __builtin_popcountl #else |