Re: [RFC][PATCH] introduce ptr_diff()

David Howells
2010-08-19T12:03:21Z

Namhyung Kim <namhyung@gmail.com> wrote:

> + if (is_power_of_2(__size)) \
> + __diff = (__addr1 - __addr2) >> ilog2(__size); \
> + else \
> + __diff = (__addr1 - __addr2) / __size; \

You shouldn't need to do this. The compiler's optimiser should switch a
divide to a shift for a power-of-2 divisor.

David