Re: [PATCH 1/2] vfio powerpc: enabled on powernv platform

From: Paul Mackerras
Date: Sun Feb 24 2013 - 21:22:24 EST


On Mon, Feb 11, 2013 at 03:16:43PM -0700, Alex Williamson wrote:
>
> Why do these all return long (vs int)? Is this a POWER-ism?

On ppc64 the compiler tends to generate slightly shorter code with
longs than with ints. The reason is that with ints the compiler has
to put in "extend sign word" instructions to convert 64-bit values
from arithmetic instructions to values in the 32-bit range.

Paul.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/