Pull preparatory gcc intrisics bswap patch from David Woodhouse:
"This single patch is effectively a no-op for now. It enables
architectures to opt in to using GCC's __builtin_bswapXX() intrinsics
for byteswapping, and if we merge this now then the architecture
maintainers can enable it for their arch during the next cycle without
dependency issues.
It's worth making it a par-arch opt-in, because although in *theory*
the compiler should never do worse than hand-coded assembler (and of
course it also ought to do a lot better on platforms like Atom and
PowerPC which have load-and-swap or store-and-swap instructions), that
isn't always the case. See
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46453
for example."
* tag 'byteswap-for-linus-
20121219' of git://git.infradead.org/users/dwmw2/byteswap:
byteorder: allow arch to opt to use GCC intrinsics for byteswapping