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Re: Please do not yell at people for trying to help you.
On Fri, Nov 12, 2010 at 06:35:32PM +0000, Eduardo Horvath wrote:
> Take, for example, the simple act of byte swapping network data. x86 has
> a bswap instruction. SPARC and PowerPC architectures have a multiplexer
> on the load/store. (Don't know about MIPS, don't remember about ARM.) In
> order to swap a 64-bit value in registers you need to issue a series of
> shift, mask, and or instrutions, usually about 8 of them, most of which
> are depenent (cannot be issued in parallel on a superscalar machine).
> The macro NetBSD uses here is bswap64(). This maps very well to the x86
> instruction, but is really not usable for any machine that does the
> swapping in the load/store path. Instead we could use something like
> load_be64()/load_le64()/store_be64()/store_le64() which could be mapped to
> a reverse-endian load/store instruction on architetures that support it
> and bswap on x86.
If you look at sys/endian.h, that is exactly the kind of abstraction the
API makes easy to use. Just provide the proper inline functions for your
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