mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-02 06:46:42 +07:00
9a858dc7ce
gcc 4.6+ has support for a externally_visible attribute that prevents the optimizer from optimizing unused symbols away. Add a __visible macro to use it with that compiler version or later. This is used (at least) by the "Link Time Optimization" patchset. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
66 lines
2.3 KiB
C
66 lines
2.3 KiB
C
#ifndef __LINUX_COMPILER_H
|
|
#error "Please don't include <linux/compiler-gcc4.h> directly, include <linux/compiler.h> instead."
|
|
#endif
|
|
|
|
/* GCC 4.1.[01] miscompiles __weak */
|
|
#ifdef __KERNEL__
|
|
# if __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ <= 1
|
|
# error Your version of gcc miscompiles the __weak directive
|
|
# endif
|
|
#endif
|
|
|
|
#define __used __attribute__((__used__))
|
|
#define __must_check __attribute__((warn_unused_result))
|
|
#define __compiler_offsetof(a,b) __builtin_offsetof(a,b)
|
|
|
|
#if __GNUC_MINOR__ >= 3
|
|
/* Mark functions as cold. gcc will assume any path leading to a call
|
|
to them will be unlikely. This means a lot of manual unlikely()s
|
|
are unnecessary now for any paths leading to the usual suspects
|
|
like BUG(), printk(), panic() etc. [but let's keep them for now for
|
|
older compilers]
|
|
|
|
Early snapshots of gcc 4.3 don't support this and we can't detect this
|
|
in the preprocessor, but we can live with this because they're unreleased.
|
|
Maketime probing would be overkill here.
|
|
|
|
gcc also has a __attribute__((__hot__)) to move hot functions into
|
|
a special section, but I don't see any sense in this right now in
|
|
the kernel context */
|
|
#define __cold __attribute__((__cold__))
|
|
|
|
#define __linktime_error(message) __attribute__((__error__(message)))
|
|
|
|
#if __GNUC_MINOR__ >= 5
|
|
/*
|
|
* Mark a position in code as unreachable. This can be used to
|
|
* suppress control flow warnings after asm blocks that transfer
|
|
* control elsewhere.
|
|
*
|
|
* Early snapshots of gcc 4.5 don't support this and we can't detect
|
|
* this in the preprocessor, but we can live with this because they're
|
|
* unreleased. Really, we need to have autoconf for the kernel.
|
|
*/
|
|
#define unreachable() __builtin_unreachable()
|
|
|
|
/* Mark a function definition as prohibited from being cloned. */
|
|
#define __noclone __attribute__((__noclone__))
|
|
|
|
#endif
|
|
#endif
|
|
|
|
#if __GNUC_MINOR__ >= 6
|
|
/*
|
|
* Tell the optimizer that something else uses this function or variable.
|
|
*/
|
|
#define __visible __attribute__((externally_visible))
|
|
#endif
|
|
|
|
#if __GNUC_MINOR__ > 0
|
|
#define __compiletime_object_size(obj) __builtin_object_size(obj, 0)
|
|
#endif
|
|
#if __GNUC_MINOR__ >= 4 && !defined(__CHECKER__)
|
|
#define __compiletime_warning(message) __attribute__((warning(message)))
|
|
#define __compiletime_error(message) __attribute__((error(message)))
|
|
#endif
|