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savanovich/likely.c

Last active August 29, 2015 14:12
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C: likely / unlikely userspace macros
Raw
likely.c
#if __GNUC__ >= 3
# define likely(x) __builtin_expect(!!(x), 1)
# define unlikely(x) __builtin_expect(!!(x), 0)
#else
# define likely(x) (x)
# define unlikely(x) (x)
#endif
Raw
likely2.c
#ifndef UNLIKELY_H
#define UNLIKELY_H
#if defined(__GNUC__) && (__GNUC__ > 2) && defined(__OPTIMIZE__)
#define likely(expr) __builtin_expect((expr), 1)
#define unlikely(expr) __builtin_expect((expr), 0)
#else
#define likely(expr) (expr)
#define unlikely(expr) (expr)
#endif
#endif
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