Pawel Jakub Dawidek <[email protected]> writes: > http://people.freebsd.org/~pjd/patches/harvest_device_attach.2.patch You can replace highbit(x) - 9 with flsll(x) - 10. Unfortunately, we don't have flsll() in the kernel, but here's a simple implementation: /* * Find last bit set in an unsigned long long. Assumes that ULL is * always 64 bits wide while UL may be either 32 or 64 bits wide. */ static __inline unsigned int flsll(unsigned long long mask) { #ifdef __LP64__ return (flsl(mask)); #else return (mask >> 32 ? 32 + flsl(mask >> 32) : flsl(mask)); #endif } On i386 and amd64, flsl() is an inline function that expands to a single assembler instruction. On all other platforms, it is a function in libkern, which is stupid - gcc and clang have builtin functions for it which are almost certainly faster than a function call. Same goes for s/last bit/first bit/; s/fls/ffs/g. DES --=20 Dag-Erling Sm=C3=B8rgrav - [email protected] _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-security To unsubscribe, send any mail to "[email protected]"