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

[David Howells]

Namhyung Kim <namhyung@xxxxxxxxx> 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
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