X-Git-Url: http://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=include%2Furcu%2Fcompiler.h;fp=include%2Furcu%2Fcompiler.h;h=511dbdf302456d46329bce98e1147b7c34a51543;hp=0000000000000000000000000000000000000000;hb=6893800a4d1cc14dff0395ddcd660a5138db183d;hpb=a59f39055b5ecb77b68cf78b9839aa9e8e4ec332 diff --git a/include/urcu/compiler.h b/include/urcu/compiler.h new file mode 100644 index 0000000..511dbdf --- /dev/null +++ b/include/urcu/compiler.h @@ -0,0 +1,130 @@ +#ifndef _URCU_COMPILER_H +#define _URCU_COMPILER_H + +/* + * compiler.h + * + * Compiler definitions. + * + * Copyright (c) 2009 Mathieu Desnoyers + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + */ + +#include /* for offsetof */ + +#define caa_likely(x) __builtin_expect(!!(x), 1) +#define caa_unlikely(x) __builtin_expect(!!(x), 0) + +#define cmm_barrier() __asm__ __volatile__ ("" : : : "memory") + +/* + * Instruct the compiler to perform only a single access to a variable + * (prohibits merging and refetching). The compiler is also forbidden to reorder + * successive instances of CMM_ACCESS_ONCE(), but only when the compiler is aware of + * particular ordering. Compiler ordering can be ensured, for example, by + * putting two CMM_ACCESS_ONCE() in separate 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 CMM_ACCESS_ONCE(x) (*(__volatile__ __typeof__(x) *)&(x)) + +#ifndef caa_max +#define caa_max(a,b) ((a)>(b)?(a):(b)) +#endif + +#ifndef caa_min +#define caa_min(a,b) ((a)<(b)?(a):(b)) +#endif + +#if defined(__SIZEOF_LONG__) +#define CAA_BITS_PER_LONG (__SIZEOF_LONG__ * 8) +#elif defined(_LP64) +#define CAA_BITS_PER_LONG 64 +#else +#define CAA_BITS_PER_LONG 32 +#endif + +/* + * caa_container_of - Get the address of an object containing a field. + * + * @ptr: pointer to the field. + * @type: type of the object. + * @member: name of the field within the object. + */ +#define caa_container_of(ptr, type, member) \ + __extension__ \ + ({ \ + const __typeof__(((type *) NULL)->member) * __ptr = (ptr); \ + (type *)((char *)__ptr - offsetof(type, member)); \ + }) + +#define CAA_BUILD_BUG_ON_ZERO(cond) (sizeof(struct { int:-!!(cond); })) +#define CAA_BUILD_BUG_ON(cond) ((void)CAA_BUILD_BUG_ON_ZERO(cond)) + +/* + * __rcu is an annotation that documents RCU pointer accesses that need + * to be protected by a read-side critical section. Eventually, a static + * checker will be able to use this annotation to detect incorrect RCU + * usage. + */ +#define __rcu + +#ifdef __cplusplus +#define URCU_FORCE_CAST(type, arg) (reinterpret_cast(arg)) +#else +#define URCU_FORCE_CAST(type, arg) ((type) (arg)) +#endif + +#define caa_is_signed_type(type) ((type) -1 < (type) 0) + +/* + * Cast to unsigned long, sign-extending if @v is signed. + * Note: casting to a larger type or to same type size keeps the sign of + * the expression being cast (see C99 6.3.1.3). + */ +#define caa_cast_long_keep_sign(v) ((unsigned long) (v)) + +#if defined (__GNUC__) \ + && ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5) \ + || __GNUC__ >= 5) +#define CDS_DEPRECATED(msg) \ + __attribute__((deprecated(msg))) +#else +#define CDS_DEPRECATED(msg) \ + __attribute__((deprecated)) +#endif + +#define CAA_ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) + +/* + * Don't allow compiling with buggy compiler. + */ + +#ifdef __GNUC__ +# define URCU_GCC_VERSION (__GNUC__ * 10000 \ + + __GNUC_MINOR__ * 100 \ + + __GNUC_PATCHLEVEL__) + +/* + * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58854 + */ +# ifdef __ARMEL__ +# if URCU_GCC_VERSION >= 40800 && URCU_GCC_VERSION <= 40802 +# error Your gcc version produces clobbered frame accesses +# endif +# endif +#endif + +#endif /* _URCU_COMPILER_H */