Interestingly the Linux kernel has this for find-last-set:
static inline unsigned long __fls(unsigned long word)
{
asm("bsr %1,%0"
:"=r" (word)
:"rm" (word));
return word;
}
spandsp has this (Everything non-x86 has been removed):
static __inline__ int top_bit(unsigned int bits)
{
int res;
__asm__ (" xorl %[res],%[res];\n"
" decl %[res];\n"
" bsrl %[bits],%[res]\n"
: [res] "=&r" (res)
: [bits] "rm" (bits));
return res;
}
I haven't measured which one is best.
/Benny
_______________________________________________
-- Bandwidth and Colocation Provided by http://www.api-digital.com --
asterisk-users mailing list
To UNSUBSCRIBE or update options visit:
http://lists.digium.com/mailman/listinfo/asterisk-users
