1 #ifndef __LINUX_COMPILER_H 2 #define __LINUX_COMPILER_H 3 4 #ifndef __ASSEMBLY__ 5 6 #ifdef __CHECKER__ 7 # define __user __attribute__((noderef, address_space(1))) 8 # define __kernel /* default address space */ 9 # define __safe __attribute__((safe)) 10 # define __force __attribute__((force)) 11 # define __nocast __attribute__((nocast)) 12 # define __iomem __attribute__((noderef, address_space(2))) 13 # define __acquires(x) __attribute__((context(x,0,1))) 14 # define __releases(x) __attribute__((context(x,1,0))) 15 # define __acquire(x) __context__(x,1) 16 # define __release(x) __context__(x,-1) 17 # define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0) 18 extern void __chk_user_ptr(const volatile void __user *); 19 extern void __chk_io_ptr(const volatile void __iomem *); 20 #else 21 # define __user 22 # define __kernel 23 # define __safe 24 # define __force 25 # define __nocast 26 # define __iomem 27 # define __chk_user_ptr(x) (void)0 28 # define __chk_io_ptr(x) (void)0 29 # define __builtin_warning(x, y...) (1) 30 # define __acquires(x) 31 # define __releases(x) 32 # define __acquire(x) (void)0 33 # define __release(x) (void)0 34 # define __cond_lock(x,c) (c) 35 #endif 36 37 #ifdef __KERNEL__ 38 39 #if __GNUC__ >= 4 40 # include <linux/compiler-gcc4.h> 41 #elif __GNUC__ == 3 && __GNUC_MINOR__ >= 2 42 # include <linux/compiler-gcc3.h> 43 #else 44 # error Sorry, your compiler is too old/not recognized. 45 #endif 46 47 /* Intel compiler defines __GNUC__. So we will overwrite implementations 48 * coming from above header files here 49 */ 50 #ifdef __INTEL_COMPILER 51 # include <linux/compiler-intel.h> 52 #endif 53 54 /* 55 * Generic compiler-dependent macros required for kernel 56 * build go below this comment. Actual compiler/compiler version 57 * specific implementations come from the above header files 58 */ 59 60 #define likely(x) __builtin_expect(!!(x), 1) 61 #define unlikely(x) __builtin_expect(!!(x), 0) 62 63 /* Optimization barrier */ 64 #ifndef barrier 65 # define barrier() __memory_barrier() 66 #endif 67 68 #ifndef RELOC_HIDE 69 # define RELOC_HIDE(ptr, off) \ 70 ({ unsigned long __ptr; \ 71 __ptr = (unsigned long) (ptr); \ 72 (typeof(ptr)) (__ptr + (off)); }) 73 #endif 74 75 #endif /* __KERNEL__ */ 76 77 #endif /* __ASSEMBLY__ */ 78 79 #ifdef __KERNEL__ 80 /* 81 * Allow us to mark functions as 'deprecated' and have gcc emit a nice 82 * warning for each use, in hopes of speeding the functions removal. 83 * Usage is: 84 * int __deprecated foo(void) 85 */ 86 #ifndef __deprecated 87 # define __deprecated /* unimplemented */ 88 #endif 89 90 #ifdef MODULE 91 #define __deprecated_for_modules __deprecated 92 #else 93 #define __deprecated_for_modules 94 #endif 95 96 #ifndef __must_check 97 #define __must_check 98 #endif 99 100 #ifndef CONFIG_ENABLE_MUST_CHECK 101 #undef __must_check 102 #define __must_check 103 #endif 104 105 /* 106 * Allow us to avoid 'defined but not used' warnings on functions and data, 107 * as well as force them to be emitted to the assembly file. 108 * 109 * As of gcc 3.4, static functions that are not marked with attribute((used)) 110 * may be elided from the assembly file. As of gcc 3.4, static data not so 111 * marked will not be elided, but this may change in a future gcc version. 112 * 113 * NOTE: Because distributions shipped with a backported unit-at-a-time 114 * compiler in gcc 3.3, we must define __used to be __attribute__((used)) 115 * for gcc >=3.3 instead of 3.4. 116 * 117 * In prior versions of gcc, such functions and data would be emitted, but 118 * would be warned about except with attribute((unused)). 119 * 120 * Mark functions that are referenced only in inline assembly as __used so 121 * the code is emitted even though it appears to be unreferenced. 122 */ 123 #ifndef __attribute_used__ 124 # define __attribute_used__ /* deprecated */ 125 #endif 126 127 #ifndef __used 128 # define __used /* unimplemented */ 129 #endif 130 131 #ifndef __maybe_unused 132 # define __maybe_unused /* unimplemented */ 133 #endif 134 135 #ifndef noinline 136 #define noinline 137 #endif 138 139 #ifndef __always_inline 140 #define __always_inline inline 141 #endif 142 143 #endif /* __KERNEL__ */ 144 145 /* 146 * From the GCC manual: 147 * 148 * Many functions do not examine any values except their arguments, 149 * and have no effects except the return value. Basically this is 150 * just slightly more strict class than the `pure' attribute above, 151 * since function is not allowed to read global memory. 152 * 153 * Note that a function that has pointer arguments and examines the 154 * data pointed to must _not_ be declared `const'. Likewise, a 155 * function that calls a non-`const' function usually must not be 156 * `const'. It does not make sense for a `const' function to return 157 * `void'. 158 */ 159 #ifndef __attribute_const__ 160 # define __attribute_const__ /* unimplemented */ 161 #endif 162 163 /* 164 * Tell gcc if a function is cold. The compiler will assume any path 165 * directly leading to the call is unlikely. 166 */ 167 168 #ifndef __cold 169 #define __cold 170 #endif 171 172 #endif /* __LINUX_COMPILER_H */ 173