Name

fls — find last set bit in word

Synopsis

int fls (int x);
 

Arguments

int x

the word to search

Description

This is defined in a similar way as the libc and compiler builtin ffs, but returns the position of the most significant set bit.

fls(value) returns 0 if value is 0 or the position of the last set bit if value is nonzero. The last (most significant) bit is at position 32.