diff options
| author | Linus Torvalds | 2012-12-19 07:52:48 -0800 |
|---|---|---|
| committer | Linus Torvalds | 2012-12-19 07:52:48 -0800 |
| commit | 7f2de8171ddf28fdb2ca7f9a683ee1207849f718 (patch) | |
| tree | d89da981ac762de3fd32e1c08ddc8041f3c37519 /include/linux | |
| parent | 59771079c18c44e39106f0f30054025acafadb41 (diff) | |
| parent | cf66bb93e0f75e0a4ba1ec070692618fa028e994 (diff) | |
Merge tag 'byteswap-for-linus-20121219' of git://git.infradead.org/users/dwmw2/byteswap
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
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/compiler-gcc4.h | 10 | ||||
| -rw-r--r-- | include/linux/compiler-intel.h | 7 |
2 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/compiler-gcc4.h b/include/linux/compiler-gcc4.h index 412bc6c2b023..dc16a858e77c 100644 --- a/include/linux/compiler-gcc4.h +++ b/include/linux/compiler-gcc4.h @@ -63,3 +63,13 @@ #define __compiletime_warning(message) __attribute__((warning(message))) #define __compiletime_error(message) __attribute__((error(message))) #endif + +#ifdef CONFIG_ARCH_USE_BUILTIN_BSWAP +#if __GNUC_MINOR__ >= 4 +#define __HAVE_BUILTIN_BSWAP32__ +#define __HAVE_BUILTIN_BSWAP64__ +#endif +#if __GNUC_MINOR__ >= 8 || (defined(__powerpc__) && __GNUC_MINOR__ >= 6) +#define __HAVE_BUILTIN_BSWAP16__ +#endif +#endif diff --git a/include/linux/compiler-intel.h b/include/linux/compiler-intel.h index d8e636e5607d..973ce10c40b6 100644 --- a/include/linux/compiler-intel.h +++ b/include/linux/compiler-intel.h @@ -29,3 +29,10 @@ #endif #define uninitialized_var(x) x + +#ifndef __HAVE_BUILTIN_BSWAP16__ +/* icc has this, but it's called _bswap16 */ +#define __HAVE_BUILTIN_BSWAP16__ +#define __builtin_bswap16 _bswap16 +#endif + |