21 #ifndef AVUTIL_INTMATH_H
22 #define AVUTIL_INTMATH_H
38 #if HAVE_FAST_CLZ && AV_GCC_VERSION_AT_LEAST(3,4)
41 # define ff_log2(x) (31 - __builtin_clz((x)|1))
42 # ifndef ff_log2_16bit
43 # define ff_log2_16bit av_log2
52 #define ff_log2 ff_log2_c
71 #define ff_log2_16bit ff_log2_16bit_c
85 #define av_log2 ff_log2
86 #define av_log2_16bit ff_log2_16bit
97 #if HAVE_FAST_CLZ && AV_GCC_VERSION_AT_LEAST(3,4)
99 #define ff_ctz(v) __builtin_ctz(v)
104 #define ff_ctz ff_ctz_c
int av_ctz(int v)
Trailing zero bit count.
static av_always_inline av_const int ff_log2_c(unsigned int v)
static av_always_inline av_const int ff_ctz_c(int v)
const uint8_t ff_log2_tab[256]
Macro definitions for various function/variable attributes.
static av_always_inline av_const int ff_log2_16bit_c(unsigned int v)