[lkml]   [2005]   [Jul]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] speed up on find_first_bit for i386 (let compiler do the work)
On Thu, 28 Jul 2005, Linus Torvalds wrote:

> > Since you're considering GCC-generated code for ffs(), ffz() and friends,
> > how about trying __builtin_ffs(), __builtin_clz() and __builtin_ctz() as
> > apropriate?
> Please don't. Try again in three years when everybody has them.

Well, __builtin_ffs() has been there since at least gcc 2.95. The two
others are quite recent, indeed -- apparently only since GCC 3.4. They
may still be considered to be used conditionally if there is justified

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-07-29 17:14    [W:0.119 / U:2.320 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site