[U-Boot] [PATCH] Avoid use of divides in print_size.

[Timur Tabi]

On Mon, May 10, 2010 at 4:51 AM, Nick Thompson <nick.thompson at ge.com> wrote:
> Modification of print_size to avoid use of divides and especially
> long long divides. Keep the binary scale factor in terms of bit
> shifts instead. This should be faster, since the previous code
> gave the compiler no clues that the divides where always powers
> of two, preventing optimisation.
>
> Signed-off-by: Nick Thompson <nick.thompson at ge.com>

This code almost works.  It seems to have trouble printing fractional
values.  Using this loop:

		unsigned int i;

		for (i = 0; i < 63; i++)
			print_size(3ULL << i, "\n");

I get this output.  Notice that it rounds 1.5 to 2 on sizes less than
a terabyte.

3 Bytes
6 Bytes
12 Bytes
24 Bytes
48 Bytes
96 Bytes
192 Bytes
384 Bytes
768 Bytes
2 KiB
3 KiB
6 KiB
12 KiB
24 KiB
48 KiB
96 KiB
192 KiB
384 KiB
768 KiB
2 MiB
3 MiB
6 MiB
12 MiB
24 MiB
48 MiB
96 MiB
192 MiB
384 MiB
768 MiB
2 GiB
3 GiB
6 GiB
12 GiB
24 GiB
48 GiB
96 GiB
192 GiB
384 GiB
768 GiB
1.5 TiB
3 TiB
6 TiB
12 TiB
24 TiB
48 TiB
96 TiB
192 TiB
384 TiB
768 TiB
1.5 PiB
3 PiB
6 PiB
12 PiB
24 PiB
48 PiB
96 PiB
192 PiB
384 PiB
768 PiB
1.5 EiB
3 EiB
6 EiB
12 EiB


-- 
Timur Tabi
Linux kernel developer at Freescale