Robert P. J. Day | 94f582f | 2007-10-16 23:26:11 -0700 | [diff] [blame] | 1 | #ifndef __LINUX_COMPILER_H |
| 2 | #error "Please don't include <linux/compiler-gcc4.h> directly, include <linux/compiler.h> instead." |
| 3 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | |
Linus Torvalds | f9d1425 | 2009-01-02 09:29:43 -0800 | [diff] [blame] | 5 | /* GCC 4.1.[01] miscompiles __weak */ |
H. Peter Anvin | 8cd2c29 | 2009-02-25 15:22:19 -0800 | [diff] [blame] | 6 | #ifdef __KERNEL__ |
| 7 | # if __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ <= 1 |
| 8 | # error Your version of gcc miscompiles the __weak directive |
| 9 | # endif |
Linus Torvalds | f9d1425 | 2009-01-02 09:29:43 -0800 | [diff] [blame] | 10 | #endif |
| 11 | |
David Rientjes | 0d7ebbb | 2007-05-09 02:35:27 -0700 | [diff] [blame] | 12 | #define __used __attribute__((__used__)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #define __must_check __attribute__((warn_unused_result)) |
| 14 | #define __compiler_offsetof(a,b) __builtin_offsetof(a,b) |
Andi Kleen | a586df0 | 2007-07-21 17:10:00 +0200 | [diff] [blame] | 15 | |
Daniel Santos | 6640dfd | 2013-02-21 16:41:32 -0800 | [diff] [blame] | 16 | #if __GNUC_MINOR__ > 0 |
| 17 | # define __compiletime_object_size(obj) __builtin_object_size(obj, 0) |
| 18 | #endif |
| 19 | |
Linus Torvalds | f153b82 | 2009-01-02 09:23:03 -0800 | [diff] [blame] | 20 | #if __GNUC_MINOR__ >= 3 |
Andi Kleen | a586df0 | 2007-07-21 17:10:00 +0200 | [diff] [blame] | 21 | /* Mark functions as cold. gcc will assume any path leading to a call |
| 22 | to them will be unlikely. This means a lot of manual unlikely()s |
| 23 | are unnecessary now for any paths leading to the usual suspects |
| 24 | like BUG(), printk(), panic() etc. [but let's keep them for now for |
| 25 | older compilers] |
| 26 | |
| 27 | Early snapshots of gcc 4.3 don't support this and we can't detect this |
| 28 | in the preprocessor, but we can live with this because they're unreleased. |
| 29 | Maketime probing would be overkill here. |
| 30 | |
| 31 | gcc also has a __attribute__((__hot__)) to move hot functions into |
| 32 | a special section, but I don't see any sense in this right now in |
| 33 | the kernel context */ |
| 34 | #define __cold __attribute__((__cold__)) |
| 35 | |
David Daney | 1399ff8 | 2012-01-10 15:07:25 -0800 | [diff] [blame] | 36 | #define __linktime_error(message) __attribute__((__error__(message))) |
David Daney | 38938c8 | 2009-12-04 17:44:50 -0800 | [diff] [blame] | 37 | |
Rusty Russell | 6f33d58 | 2012-11-22 12:30:25 +1030 | [diff] [blame] | 38 | #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) |
| 39 | |
Daniel Santos | 6640dfd | 2013-02-21 16:41:32 -0800 | [diff] [blame] | 40 | #ifndef __CHECKER__ |
| 41 | # define __compiletime_warning(message) __attribute__((warning(message))) |
| 42 | # define __compiletime_error(message) __attribute__((error(message))) |
| 43 | #endif /* __CHECKER__ */ |
| 44 | #endif /* __GNUC_MINOR__ >= 3 */ |
| 45 | |
David Daney | 38938c8 | 2009-12-04 17:44:50 -0800 | [diff] [blame] | 46 | #if __GNUC_MINOR__ >= 5 |
| 47 | /* |
| 48 | * Mark a position in code as unreachable. This can be used to |
| 49 | * suppress control flow warnings after asm blocks that transfer |
| 50 | * control elsewhere. |
| 51 | * |
| 52 | * Early snapshots of gcc 4.5 don't support this and we can't detect |
| 53 | * this in the preprocessor, but we can live with this because they're |
| 54 | * unreleased. Really, we need to have autoconf for the kernel. |
| 55 | */ |
| 56 | #define unreachable() __builtin_unreachable() |
Mikael Pettersson | 9c69520 | 2010-06-29 15:05:25 -0700 | [diff] [blame] | 57 | |
| 58 | /* Mark a function definition as prohibited from being cloned. */ |
| 59 | #define __noclone __attribute__((__noclone__)) |
| 60 | |
Daniel Santos | 6640dfd | 2013-02-21 16:41:32 -0800 | [diff] [blame] | 61 | #endif /* __GNUC_MINOR__ >= 5 */ |
Arjan van de Ven | 9f0cf4a | 2009-09-26 14:33:01 +0200 | [diff] [blame] | 62 | |
Andi Kleen | 9a858dc | 2012-09-17 14:09:15 -0700 | [diff] [blame] | 63 | #if __GNUC_MINOR__ >= 6 |
| 64 | /* |
| 65 | * Tell the optimizer that something else uses this function or variable. |
| 66 | */ |
| 67 | #define __visible __attribute__((externally_visible)) |
| 68 | #endif |
| 69 | |
David Woodhouse | cf66bb9 | 2012-12-03 16:25:40 +0000 | [diff] [blame] | 70 | |
| 71 | #ifdef CONFIG_ARCH_USE_BUILTIN_BSWAP |
| 72 | #if __GNUC_MINOR__ >= 4 |
| 73 | #define __HAVE_BUILTIN_BSWAP32__ |
| 74 | #define __HAVE_BUILTIN_BSWAP64__ |
| 75 | #endif |
| 76 | #if __GNUC_MINOR__ >= 8 || (defined(__powerpc__) && __GNUC_MINOR__ >= 6) |
| 77 | #define __HAVE_BUILTIN_BSWAP16__ |
| 78 | #endif |
| 79 | #endif |