blob: fae2045b9afcbc7fd7b97066e39e1d02c26c0d09 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
|
#ifndef I386_BITOPS_H
#define I386_BITOPS_H
/**
* log2 - Find the truncated log base 2 of x
*/
static inline unsigned long log2(unsigned long x)
{
unsigned long r = 0;
__asm__(
"bsrl %1, %0\n\t"
"jnz 1f\n\t"
"movl $-1, %0\n\t"
"1:\n\t"
: "=r" (r) : "r" (x));
return r;
}
#endif /* I386_BITOPS_H */
|