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-rw-r--r--include/linux/compiler.h303
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diff --git a/include/linux/compiler.h b/include/linux/compiler.h
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+++ b/include/linux/compiler.h
@@ -0,0 +1,303 @@
+#ifndef __LINUX_COMPILER_H
+#define __LINUX_COMPILER_H
+
+#ifndef __ASSEMBLY__
+
+#ifdef __CHECKER__
+# define __user __attribute__((noderef, address_space(1)))
+# define __kernel /* default address space */
+# define __safe __attribute__((safe))
+# define __force __attribute__((force))
+# define __nocast __attribute__((nocast))
+# define __iomem __attribute__((noderef, address_space(2)))
+# define __acquires(x) __attribute__((context(x,0,1)))
+# define __releases(x) __attribute__((context(x,1,0)))
+# define __acquire(x) __context__(x,1)
+# define __release(x) __context__(x,-1)
+# define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0)
+extern void __chk_user_ptr(const volatile void __user *);
+extern void __chk_io_ptr(const volatile void __iomem *);
+#else
+# define __user
+# define __kernel
+# define __safe
+# define __force
+# define __nocast
+# define __iomem
+# define __chk_user_ptr(x) (void)0
+# define __chk_io_ptr(x) (void)0
+# define __builtin_warning(x, y...) (1)
+# define __acquires(x)
+# define __releases(x)
+# define __acquire(x) (void)0
+# define __release(x) (void)0
+# define __cond_lock(x,c) (c)
+#endif
+
+#ifdef __KERNEL__
+
+#ifdef __GNUC__
+#include <linux/compiler-gcc.h>
+#endif
+
+#define notrace __attribute__((no_instrument_function))
+
+/* Intel compiler defines __GNUC__. So we will overwrite implementations
+ * coming from above header files here
+ */
+#ifdef __INTEL_COMPILER
+# include <linux/compiler-intel.h>
+#endif
+
+/*
+ * Generic compiler-dependent macros required for kernel
+ * build go below this comment. Actual compiler/compiler version
+ * specific implementations come from the above header files
+ */
+
+struct ftrace_branch_data {
+ const char *func;
+ const char *file;
+ unsigned line;
+ union {
+ struct {
+ unsigned long correct;
+ unsigned long incorrect;
+ };
+ struct {
+ unsigned long miss;
+ unsigned long hit;
+ };
+ unsigned long miss_hit[2];
+ };
+};
+
+/*
+ * Note: DISABLE_BRANCH_PROFILING can be used by special lowlevel code
+ * to disable branch tracing on a per file basis.
+ */
+#if defined(CONFIG_TRACE_BRANCH_PROFILING) \
+ && !defined(DISABLE_BRANCH_PROFILING) && !defined(__CHECKER__)
+void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect);
+
+#define likely_notrace(x) __builtin_expect(!!(x), 1)
+#define unlikely_notrace(x) __builtin_expect(!!(x), 0)
+
+#define __branch_check__(x, expect) ({ \
+ int ______r; \
+ static struct ftrace_branch_data \
+ __attribute__((__aligned__(4))) \
+ __attribute__((section("_ftrace_annotated_branch"))) \
+ ______f = { \
+ .func = __func__, \
+ .file = __FILE__, \
+ .line = __LINE__, \
+ }; \
+ ______r = likely_notrace(x); \
+ ftrace_likely_update(&______f, ______r, expect); \
+ ______r; \
+ })
+
+/*
+ * Using __builtin_constant_p(x) to ignore cases where the return
+ * value is always the same. This idea is taken from a similar patch
+ * written by Daniel Walker.
+ */
+# ifndef likely
+# define likely(x) (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 1))
+# endif
+# ifndef unlikely
+# define unlikely(x) (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 0))
+# endif
+
+#ifdef CONFIG_PROFILE_ALL_BRANCHES
+/*
+ * "Define 'is'", Bill Clinton
+ * "Define 'if'", Steven Rostedt
+ */
+#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
+#define __trace_if(cond) \
+ if (__builtin_constant_p((cond)) ? !!(cond) : \
+ ({ \
+ int ______r; \
+ static struct ftrace_branch_data \
+ __attribute__((__aligned__(4))) \
+ __attribute__((section("_ftrace_branch"))) \
+ ______f = { \
+ .func = __func__, \
+ .file = __FILE__, \
+ .line = __LINE__, \
+ }; \
+ ______r = !!(cond); \
+ ______f.miss_hit[______r]++; \
+ ______r; \
+ }))
+#endif /* CONFIG_PROFILE_ALL_BRANCHES */
+
+#else
+# define likely(x) __builtin_expect(!!(x), 1)
+# define unlikely(x) __builtin_expect(!!(x), 0)
+#endif
+
+/* Optimization barrier */
+#ifndef barrier
+# define barrier() __memory_barrier()
+#endif
+
+/* Unreachable code */
+#ifndef unreachable
+# define unreachable() do { } while (1)
+#endif
+
+#ifndef RELOC_HIDE
+# define RELOC_HIDE(ptr, off) \
+ ({ unsigned long __ptr; \
+ __ptr = (unsigned long) (ptr); \
+ (typeof(ptr)) (__ptr + (off)); })
+#endif
+
+#endif /* __KERNEL__ */
+
+#endif /* __ASSEMBLY__ */
+
+#ifdef __KERNEL__
+/*
+ * Allow us to mark functions as 'deprecated' and have gcc emit a nice
+ * warning for each use, in hopes of speeding the functions removal.
+ * Usage is:
+ * int __deprecated foo(void)
+ */
+#ifndef __deprecated
+# define __deprecated /* unimplemented */
+#endif
+
+#ifdef MODULE
+#define __deprecated_for_modules __deprecated
+#else
+#define __deprecated_for_modules
+#endif
+
+#ifndef __must_check
+#define __must_check
+#endif
+
+#ifndef CONFIG_ENABLE_MUST_CHECK
+#undef __must_check
+#define __must_check
+#endif
+#ifndef CONFIG_ENABLE_WARN_DEPRECATED
+#undef __deprecated
+#undef __deprecated_for_modules
+#define __deprecated
+#define __deprecated_for_modules
+#endif
+
+/*
+ * Allow us to avoid 'defined but not used' warnings on functions and data,
+ * as well as force them to be emitted to the assembly file.
+ *
+ * As of gcc 3.4, static functions that are not marked with attribute((used))
+ * may be elided from the assembly file. As of gcc 3.4, static data not so
+ * marked will not be elided, but this may change in a future gcc version.
+ *
+ * NOTE: Because distributions shipped with a backported unit-at-a-time
+ * compiler in gcc 3.3, we must define __used to be __attribute__((used))
+ * for gcc >=3.3 instead of 3.4.
+ *
+ * In prior versions of gcc, such functions and data would be emitted, but
+ * would be warned about except with attribute((unused)).
+ *
+ * Mark functions that are referenced only in inline assembly as __used so
+ * the code is emitted even though it appears to be unreferenced.
+ */
+#ifndef __used
+# define __used /* unimplemented */
+#endif
+
+#ifndef __maybe_unused
+# define __maybe_unused /* unimplemented */
+#endif
+
+#ifndef __always_unused
+# define __always_unused /* unimplemented */
+#endif
+
+#ifndef noinline
+#define noinline
+#endif
+
+/*
+ * Rather then using noinline to prevent stack consumption, use
+ * noinline_for_stack instead. For documentaiton reasons.
+ */
+#define noinline_for_stack noinline
+
+#ifndef __always_inline
+#define __always_inline inline
+#endif
+
+#endif /* __KERNEL__ */
+
+/*
+ * From the GCC manual:
+ *
+ * Many functions do not examine any values except their arguments,
+ * and have no effects except the return value. Basically this is
+ * just slightly more strict class than the `pure' attribute above,
+ * since function is not allowed to read global memory.
+ *
+ * Note that a function that has pointer arguments and examines the
+ * data pointed to must _not_ be declared `const'. Likewise, a
+ * function that calls a non-`const' function usually must not be
+ * `const'. It does not make sense for a `const' function to return
+ * `void'.
+ */
+#ifndef __attribute_const__
+# define __attribute_const__ /* unimplemented */
+#endif
+
+/*
+ * Tell gcc if a function is cold. The compiler will assume any path
+ * directly leading to the call is unlikely.
+ */
+
+#ifndef __cold
+#define __cold
+#endif
+
+/* Simple shorthand for a section definition */
+#ifndef __section
+# define __section(S) __attribute__ ((__section__(#S)))
+#endif
+
+/* Are two types/vars the same type (ignoring qualifiers)? */
+#ifndef __same_type
+# define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
+#endif
+
+/* Compile time object size, -1 for unknown */
+#ifndef __compiletime_object_size
+# define __compiletime_object_size(obj) -1
+#endif
+#ifndef __compiletime_warning
+# define __compiletime_warning(message)
+#endif
+#ifndef __compiletime_error
+# define __compiletime_error(message)
+#endif
+
+/*
+ * Prevent the compiler from merging or refetching accesses. The compiler
+ * is also forbidden from reordering successive instances of ACCESS_ONCE(),
+ * but only when the compiler is aware of some particular ordering. One way
+ * to make the compiler aware of ordering is to put the two invocations of
+ * ACCESS_ONCE() in different C statements.
+ *
+ * This macro does absolutely -nothing- to prevent the CPU from reordering,
+ * merging, or refetching absolutely anything at any time. Its main intended
+ * use is to mediate communication between process-level code and irq/NMI
+ * handlers, all running on the same CPU.
+ */
+#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x))
+
+#endif /* __LINUX_COMPILER_H */