[PATCH, AArch64] Use GCC builtins to count leading/tailing zeros

[Yufeng Zhang]

Hi Marcus,

Can you help me commit this patch please?

The patch was originally posted here:
   http://sourceware.org/ml/libc-alpha/2014-01/msg00114.html
and approved for 2.20 here:
   http://sourceware.org/ml/libc-alpha/2014-01/msg00120.html
and the corresponding gcc patch was posted here:
   http://gcc.gnu.org/ml/gcc-patches/2014-01/msg00286.html

Thanks,
Yufeng


On 01/07/14 15:25, Yufeng Zhang wrote:
> Hi,
>
> This patch defines a number of macros in stdlib/longlong.h to use GCC
> builtins __builtin_clz* to implement the __clz* and __ctz* functions.
>
> OK for the mainline?
>
> Thanks,
> Yufeng
>
>
> 	* stdlib/longlong.h (count_leading_zeros, count_trailing_zeros)
> 	(COUNT_LEADING_ZEROS_0): Define for aarch64.