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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) 18extern void __chk_user_ptr(const volatile void __user *); 19extern 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#ifndef CONFIG_ENABLE_WARN_DEPRECATED 105#undef __deprecated 106#undef __deprecated_for_modules 107#define __deprecated 108#define __deprecated_for_modules 109#endif 110 111/* 112 * Allow us to avoid 'defined but not used' warnings on functions and data, 113 * as well as force them to be emitted to the assembly file. 114 * 115 * As of gcc 3.4, static functions that are not marked with attribute((used)) 116 * may be elided from the assembly file. As of gcc 3.4, static data not so 117 * marked will not be elided, but this may change in a future gcc version. 118 * 119 * NOTE: Because distributions shipped with a backported unit-at-a-time 120 * compiler in gcc 3.3, we must define __used to be __attribute__((used)) 121 * for gcc >=3.3 instead of 3.4. 122 * 123 * In prior versions of gcc, such functions and data would be emitted, but 124 * would be warned about except with attribute((unused)). 125 * 126 * Mark functions that are referenced only in inline assembly as __used so 127 * the code is emitted even though it appears to be unreferenced. 128 */ 129#ifndef __used 130# define __used /* unimplemented */ 131#endif 132 133#ifndef __maybe_unused 134# define __maybe_unused /* unimplemented */ 135#endif 136 137#ifndef noinline 138#define noinline 139#endif 140 141/* 142 * Rather then using noinline to prevent stack consumption, use 143 * noinline_for_stack instead. For documentaiton reasons. 144 */ 145#define noinline_for_stack noinline 146 147#ifndef __always_inline 148#define __always_inline inline 149#endif 150 151#endif /* __KERNEL__ */ 152 153/* 154 * From the GCC manual: 155 * 156 * Many functions do not examine any values except their arguments, 157 * and have no effects except the return value. Basically this is 158 * just slightly more strict class than the `pure' attribute above, 159 * since function is not allowed to read global memory. 160 * 161 * Note that a function that has pointer arguments and examines the 162 * data pointed to must _not_ be declared `const'. Likewise, a 163 * function that calls a non-`const' function usually must not be 164 * `const'. It does not make sense for a `const' function to return 165 * `void'. 166 */ 167#ifndef __attribute_const__ 168# define __attribute_const__ /* unimplemented */ 169#endif 170 171/* 172 * Tell gcc if a function is cold. The compiler will assume any path 173 * directly leading to the call is unlikely. 174 */ 175 176#ifndef __cold 177#define __cold 178#endif 179 180/* Simple shorthand for a section definition */ 181#ifndef __section 182# define __section(S) __attribute__ ((__section__(#S))) 183#endif 184 185#endif /* __LINUX_COMPILER_H */