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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#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)))
Rusty Russelle0fdb0e2009-10-29 22:34:15 +09008# define __kernel __attribute__((address_space(0)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07009# define __safe __attribute__((safe))
10# define __force __attribute__((force))
11# define __nocast __attribute__((nocast))
12# define __iomem __attribute__((noderef, address_space(2)))
Josh Triplettc902e0a2006-09-30 23:28:21 -070013# 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)
Josh Triplettdcc8e552006-09-29 02:01:03 -070017# define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0)
Rusty Russelle0fdb0e2009-10-29 22:34:15 +090018# define __percpu __attribute__((noderef, address_space(3)))
Paul E. McKenneyca5ecdd2010-04-28 14:39:09 -070019#ifdef CONFIG_SPARSE_RCU_POINTER
20# define __rcu __attribute__((noderef, address_space(4)))
21#else
Paul E. McKenney71d1d5c2010-05-11 16:13:14 -070022# define __rcu
Paul E. McKenneyca5ecdd2010-04-28 14:39:09 -070023#endif
Al Viroc47ffe32007-07-26 17:35:29 +010024extern void __chk_user_ptr(const volatile void __user *);
25extern void __chk_io_ptr(const volatile void __iomem *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#else
27# define __user
28# define __kernel
29# define __safe
30# define __force
31# define __nocast
32# define __iomem
33# define __chk_user_ptr(x) (void)0
34# define __chk_io_ptr(x) (void)0
35# define __builtin_warning(x, y...) (1)
36# define __acquires(x)
37# define __releases(x)
38# define __acquire(x) (void)0
39# define __release(x) (void)0
Josh Triplettdcc8e552006-09-29 02:01:03 -070040# define __cond_lock(x,c) (c)
Rusty Russelle0fdb0e2009-10-29 22:34:15 +090041# define __percpu
Paul E. McKenney71d1d5c2010-05-11 16:13:14 -070042# define __rcu
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#endif
44
45#ifdef __KERNEL__
46
Linus Torvaldsf153b822009-01-02 09:23:03 -080047#ifdef __GNUC__
48#include <linux/compiler-gcc.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070049#endif
50
Steven Rostedt28614882008-08-14 22:47:18 -040051#define notrace __attribute__((no_instrument_function))
52
Linus Torvalds1da177e2005-04-16 15:20:36 -070053/* Intel compiler defines __GNUC__. So we will overwrite implementations
54 * coming from above header files here
55 */
56#ifdef __INTEL_COMPILER
57# include <linux/compiler-intel.h>
58#endif
59
60/*
61 * Generic compiler-dependent macros required for kernel
62 * build go below this comment. Actual compiler/compiler version
63 * specific implementations come from the above header files
64 */
65
Steven Rostedt2ed84ee2008-11-12 15:24:24 -050066struct ftrace_branch_data {
Steven Rostedt1f0d69a2008-11-12 00:14:39 -050067 const char *func;
68 const char *file;
69 unsigned line;
Steven Rostedt2bcd5212008-11-21 01:30:54 -050070 union {
71 struct {
72 unsigned long correct;
73 unsigned long incorrect;
74 };
75 struct {
76 unsigned long miss;
77 unsigned long hit;
78 };
Witold Baryluk97e7e4f2009-03-17 21:15:44 +010079 unsigned long miss_hit[2];
Steven Rostedt2bcd5212008-11-21 01:30:54 -050080 };
Steven Rostedt1f0d69a2008-11-12 00:14:39 -050081};
Steven Rostedt2ed84ee2008-11-12 15:24:24 -050082
83/*
84 * Note: DISABLE_BRANCH_PROFILING can be used by special lowlevel code
85 * to disable branch tracing on a per file basis.
86 */
Bart Van Assched9ad8bc2009-04-05 16:20:02 +020087#if defined(CONFIG_TRACE_BRANCH_PROFILING) \
88 && !defined(DISABLE_BRANCH_PROFILING) && !defined(__CHECKER__)
Steven Rostedt2ed84ee2008-11-12 15:24:24 -050089void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect);
Steven Rostedt1f0d69a2008-11-12 00:14:39 -050090
91#define likely_notrace(x) __builtin_expect(!!(x), 1)
92#define unlikely_notrace(x) __builtin_expect(!!(x), 0)
93
Steven Rostedt45b79742008-11-21 00:40:40 -050094#define __branch_check__(x, expect) ({ \
Steven Rostedt1f0d69a2008-11-12 00:14:39 -050095 int ______r; \
Steven Rostedt2ed84ee2008-11-12 15:24:24 -050096 static struct ftrace_branch_data \
Steven Rostedt1f0d69a2008-11-12 00:14:39 -050097 __attribute__((__aligned__(4))) \
Steven Rostedt45b79742008-11-21 00:40:40 -050098 __attribute__((section("_ftrace_annotated_branch"))) \
Steven Rostedt1f0d69a2008-11-12 00:14:39 -050099 ______f = { \
100 .func = __func__, \
101 .file = __FILE__, \
102 .line = __LINE__, \
103 }; \
Steven Rostedt1f0d69a2008-11-12 00:14:39 -0500104 ______r = likely_notrace(x); \
Steven Rostedt45b79742008-11-21 00:40:40 -0500105 ftrace_likely_update(&______f, ______r, expect); \
Steven Rostedt1f0d69a2008-11-12 00:14:39 -0500106 ______r; \
107 })
108
109/*
110 * Using __builtin_constant_p(x) to ignore cases where the return
111 * value is always the same. This idea is taken from a similar patch
112 * written by Daniel Walker.
113 */
114# ifndef likely
Steven Rostedt45b79742008-11-21 00:40:40 -0500115# define likely(x) (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 1))
Steven Rostedt1f0d69a2008-11-12 00:14:39 -0500116# endif
117# ifndef unlikely
Steven Rostedt45b79742008-11-21 00:40:40 -0500118# define unlikely(x) (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 0))
Steven Rostedt1f0d69a2008-11-12 00:14:39 -0500119# endif
Steven Rostedt2bcd5212008-11-21 01:30:54 -0500120
121#ifdef CONFIG_PROFILE_ALL_BRANCHES
122/*
123 * "Define 'is'", Bill Clinton
124 * "Define 'if'", Steven Rostedt
125 */
Linus Torvaldsab3c9c62009-04-07 07:59:41 -0700126#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
127#define __trace_if(cond) \
128 if (__builtin_constant_p((cond)) ? !!(cond) : \
Steven Rostedt2bcd5212008-11-21 01:30:54 -0500129 ({ \
130 int ______r; \
131 static struct ftrace_branch_data \
132 __attribute__((__aligned__(4))) \
133 __attribute__((section("_ftrace_branch"))) \
134 ______f = { \
135 .func = __func__, \
136 .file = __FILE__, \
137 .line = __LINE__, \
138 }; \
139 ______r = !!(cond); \
Witold Baryluk97e7e4f2009-03-17 21:15:44 +0100140 ______f.miss_hit[______r]++; \
Steven Rostedt2bcd5212008-11-21 01:30:54 -0500141 ______r; \
142 }))
143#endif /* CONFIG_PROFILE_ALL_BRANCHES */
144
Steven Rostedt1f0d69a2008-11-12 00:14:39 -0500145#else
146# define likely(x) __builtin_expect(!!(x), 1)
147# define unlikely(x) __builtin_expect(!!(x), 0)
148#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149
150/* Optimization barrier */
151#ifndef barrier
152# define barrier() __memory_barrier()
153#endif
154
David Daney38938c82009-12-04 17:44:50 -0800155/* Unreachable code */
156#ifndef unreachable
157# define unreachable() do { } while (1)
158#endif
159
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160#ifndef RELOC_HIDE
161# define RELOC_HIDE(ptr, off) \
162 ({ unsigned long __ptr; \
163 __ptr = (unsigned long) (ptr); \
164 (typeof(ptr)) (__ptr + (off)); })
165#endif
166
167#endif /* __KERNEL__ */
168
169#endif /* __ASSEMBLY__ */
170
David Woodhouse4f79c3f2006-05-02 10:41:25 +0100171#ifdef __KERNEL__
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172/*
173 * Allow us to mark functions as 'deprecated' and have gcc emit a nice
174 * warning for each use, in hopes of speeding the functions removal.
175 * Usage is:
176 * int __deprecated foo(void)
177 */
178#ifndef __deprecated
179# define __deprecated /* unimplemented */
180#endif
181
Paul E. McKenney512345b2005-05-01 08:59:03 -0700182#ifdef MODULE
183#define __deprecated_for_modules __deprecated
184#else
185#define __deprecated_for_modules
186#endif
187
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188#ifndef __must_check
189#define __must_check
190#endif
191
Andrew Mortoncebc04b2006-08-14 22:43:18 -0700192#ifndef CONFIG_ENABLE_MUST_CHECK
193#undef __must_check
194#define __must_check
195#endif
Jeff Garzikde488442007-10-25 04:06:13 -0400196#ifndef CONFIG_ENABLE_WARN_DEPRECATED
197#undef __deprecated
198#undef __deprecated_for_modules
199#define __deprecated
200#define __deprecated_for_modules
201#endif
Andrew Mortoncebc04b2006-08-14 22:43:18 -0700202
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203/*
204 * Allow us to avoid 'defined but not used' warnings on functions and data,
205 * as well as force them to be emitted to the assembly file.
206 *
David Rientjes0d7ebbb2007-05-09 02:35:27 -0700207 * As of gcc 3.4, static functions that are not marked with attribute((used))
208 * may be elided from the assembly file. As of gcc 3.4, static data not so
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 * marked will not be elided, but this may change in a future gcc version.
210 *
David Rientjes0d7ebbb2007-05-09 02:35:27 -0700211 * NOTE: Because distributions shipped with a backported unit-at-a-time
212 * compiler in gcc 3.3, we must define __used to be __attribute__((used))
213 * for gcc >=3.3 instead of 3.4.
214 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 * In prior versions of gcc, such functions and data would be emitted, but
216 * would be warned about except with attribute((unused)).
David Rientjes0d7ebbb2007-05-09 02:35:27 -0700217 *
218 * Mark functions that are referenced only in inline assembly as __used so
219 * the code is emitted even though it appears to be unreferenced.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220 */
David Rientjes0d7ebbb2007-05-09 02:35:27 -0700221#ifndef __used
222# define __used /* unimplemented */
223#endif
224
225#ifndef __maybe_unused
226# define __maybe_unused /* unimplemented */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227#endif
228
Li Zefan7b2a3512009-11-02 08:50:52 +0800229#ifndef __always_unused
230# define __always_unused /* unimplemented */
231#endif
232
David Woodhouse423bc7b2006-05-04 00:41:02 +0100233#ifndef noinline
234#define noinline
235#endif
236
Andrew Morton735c4fb2008-03-04 14:28:40 -0800237/*
238 * Rather then using noinline to prevent stack consumption, use
Alexander Steine6be0c92012-02-23 13:42:30 +0100239 * noinline_for_stack instead. For documentation reasons.
Andrew Morton735c4fb2008-03-04 14:28:40 -0800240 */
241#define noinline_for_stack noinline
242
David Woodhouse423bc7b2006-05-04 00:41:02 +0100243#ifndef __always_inline
244#define __always_inline inline
245#endif
246
247#endif /* __KERNEL__ */
248
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249/*
250 * From the GCC manual:
251 *
252 * Many functions do not examine any values except their arguments,
253 * and have no effects except the return value. Basically this is
254 * just slightly more strict class than the `pure' attribute above,
255 * since function is not allowed to read global memory.
256 *
257 * Note that a function that has pointer arguments and examines the
258 * data pointed to must _not_ be declared `const'. Likewise, a
259 * function that calls a non-`const' function usually must not be
260 * `const'. It does not make sense for a `const' function to return
261 * `void'.
262 */
263#ifndef __attribute_const__
264# define __attribute_const__ /* unimplemented */
265#endif
266
Andi Kleena586df02007-07-21 17:10:00 +0200267/*
268 * Tell gcc if a function is cold. The compiler will assume any path
269 * directly leading to the call is unlikely.
270 */
271
272#ifndef __cold
273#define __cold
274#endif
275
Sam Ravnborgf3fe8662008-01-20 18:54:48 +0100276/* Simple shorthand for a section definition */
277#ifndef __section
278# define __section(S) __attribute__ ((__section__(#S)))
279#endif
280
Andi Kleen9a858dc2012-09-17 14:09:15 -0700281#ifndef __visible
282#define __visible
283#endif
284
Rusty Russelld2c123c2009-06-12 21:46:56 -0600285/* Are two types/vars the same type (ignoring qualifiers)? */
286#ifndef __same_type
287# define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
288#endif
289
Arjan van de Ven9f0cf4a2009-09-26 14:33:01 +0200290/* Compile time object size, -1 for unknown */
291#ifndef __compiletime_object_size
292# define __compiletime_object_size(obj) -1
293#endif
Arjan van de Ven4a312762009-09-30 13:05:23 +0200294#ifndef __compiletime_warning
295# define __compiletime_warning(message)
296#endif
Arjan van de Ven63312b62009-10-02 07:50:50 -0700297#ifndef __compiletime_error
298# define __compiletime_error(message)
299#endif
David Daney1399ff82012-01-10 15:07:25 -0800300#ifndef __linktime_error
301# define __linktime_error(message)
302#endif
Linus Torvalds9c3cdc12008-05-10 19:51:16 -0700303/*
304 * Prevent the compiler from merging or refetching accesses. The compiler
305 * is also forbidden from reordering successive instances of ACCESS_ONCE(),
306 * but only when the compiler is aware of some particular ordering. One way
307 * to make the compiler aware of ordering is to put the two invocations of
308 * ACCESS_ONCE() in different C statements.
309 *
310 * This macro does absolutely -nothing- to prevent the CPU from reordering,
Paul E. McKenneyded00a52008-08-17 12:50:36 -0700311 * merging, or refetching absolutely anything at any time. Its main intended
312 * use is to mediate communication between process-level code and irq/NMI
313 * handlers, all running on the same CPU.
Linus Torvalds9c3cdc12008-05-10 19:51:16 -0700314 */
315#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x))
316
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317#endif /* __LINUX_COMPILER_H */