1 #ifndef __LINUX_COMPILER_H
2 #define __LINUX_COMPILER_H
5 # define __user __attribute__((noderef, address_space(1)))
6 # define __kernel /* default address space */
7 # define __safe __attribute__((safe))
8 # define __force __attribute__((force))
20 # include <linux/compiler-gcc+.h> /* catch-all for GCC 4, 5, etc. */
22 # include <linux/compiler-gcc3.h>
24 # include <linux/compiler-gcc2.h>
26 # error Sorry, your compiler is too old/not recognized.
30 /* Intel compiler defines __GNUC__. So we will overwrite implementations
31 * coming from above header files here
33 #ifdef __INTEL_COMPILER
34 # include <linux/compiler-intel.h>
38 * Generic compiler-dependent macros required for kernel
39 * build go below this comment. Actual compiler/compiler version
40 * specific implementations come from the above header files
43 #define likely(x) __builtin_expect(!!(x), 1)
44 #define unlikely(x) __builtin_expect(!!(x), 0)
50 /* Optimization barrier */
52 # define barrier() __memory_barrier()
56 # define RELOC_HIDE(ptr, off) \
57 ({ unsigned long __ptr; \
58 __ptr = (unsigned long) (ptr); \
59 (typeof(ptr)) (__ptr + (off)); })
62 #endif /* __KERNEL__ */
65 * Allow us to mark functions as 'deprecated' and have gcc emit a nice
66 * warning for each use, in hopes of speeding the functions removal.
68 * int __deprecated foo(void)
71 # define __deprecated /* unimplemented */
79 * Allow us to avoid 'defined but not used' warnings on functions and data,
80 * as well as force them to be emitted to the assembly file.
82 * As of gcc 3.3, static functions that are not marked with attribute((used))
83 * may be elided from the assembly file. As of gcc 3.3, static data not so
84 * marked will not be elided, but this may change in a future gcc version.
86 * In prior versions of gcc, such functions and data would be emitted, but
87 * would be warned about except with attribute((unused)).
89 #ifndef __attribute_used__
90 # define __attribute_used__ /* unimplemented */
94 * From the GCC manual:
96 * Many functions have no effects except the return value and their
97 * return value depends only on the parameters and/or global
98 * variables. Such a function can be subject to common subexpression
99 * elimination and loop optimization just as an arithmetic operator
103 #ifndef __attribute_pure__
104 # define __attribute_pure__ /* unimplemented */
108 * From the GCC manual:
110 * Many functions do not examine any values except their arguments,
111 * and have no effects except the return value. Basically this is
112 * just slightly more strict class than the `pure' attribute above,
113 * since function is not allowed to read global memory.
115 * Note that a function that has pointer arguments and examines the
116 * data pointed to must _not_ be declared `const'. Likewise, a
117 * function that calls a non-`const' function usually must not be
118 * `const'. It does not make sense for a `const' function to return
121 #ifndef __attribute_const__
122 # define __attribute_const__ /* unimplemented */
129 #endif /* __LINUX_COMPILER_H */